I think this shows pretty well that the 440Source heads are basically aluminum copies of factory heads with minor improvements. Also those saying the factory heads have low flow for the cubes they fed, that is true but keep in mind the BBM was first released in 1958. The common big blocks from Ford (385 series) and Chevy (Mark IV) came later and had the benefit of better knowledge about flow. Also the first BBM engines were small displacement, 350-361 initially with the raised-deck 413 soon after in 1959.
The source head is a chinese copy of the ebrock RPM 84cc head made to look like a stock cast iron casting on the outside, they could have picked a better head to copy after seeing how close in flow this 906 is to a supposed cnc's set.
@@mopartron3030 sorry it is , look at the chambers , EXACT shape , does not look like a 915 closed chamber shape , Modern ran their RPM CNC program on it and it flowed exactly the same as the cnc'd RPM. source even posted it in an online forum a number of years ago.
@@dartgts383 You need to look at as-cast flow numbers to get a fair comparison. Engine Masters did a 440 dyno test where they compared stock iron vs stealth vs RPM vs trick flow (all unported) and with each change their mild 440 picked up 15-25 hp. Not really worth arguing anyway you can get overlapping results from each type of head depending on the work done.
@@mopartron3030 You don't need to tell be about as cast numbers , when the Stealth was first released the flow numbers CLAIMED were not the flow numbers head porters whose benches I trust showed. The chinese have no problem trying to copy another companies intellectual property , they just do a half assed job at it .
I do not blame you on Porting Cast Iron. I Hate porting on Cast Iron. Aluminum I would do all day long with no issues. When I worked at Racers Edge AZ I use to do a lot of the Porting, Seat to Bowl Blending and cumbustion chamber bleanding as well after the CNC finnished them up.
Some people wouldn't even let a Mopar head touch their flow bench. One thing about Mopar fans is that they do more with less. We may be down on hp but our suspension is tricked out. It is just personal taste, it's your money, spend it on what you want. Thanks for the flow test and pointing out what works and doesn't, and why.
Eric, seeing what you do and what i always wanted to do makes me really want to get back into getting my hands dirty. Up here in northern New York there isn't alot of this kind of work going on. I am a Mopar guy but i enjoy all of them. I guess i'm going to go see an old friend that has his own transmission business to see what what kind of work is out there. Just remember this, i watch your videos because i remember the old Engine Masters Challenge and you did very well against the best engine builders ever. In short, i watch you for knowledge and inspiration; your video's may not make any money for you but they mean alot to me. Keep it up and maybe sometime soon i'll be ordering parts through you instead of Summit. I have a horsepower addiction that needs to be fed!
I’ve only spoken to him on the phone, but Porter Racing Heads in Burlington VT is an excellent mostly Mopar shop. Dwayne Porter is a wealth of knowledge on porting Mopar heads, cam design, dyno testing, class drag racing etc.
Very cool video. I'm only aware of one company that has a CNC program for 906 heads and while I've heard good things, its nice to see some independent testing. I'm personally impressed! Going back 20+ years ago, I had a unported set of 906s on a rebuilt 440. The modifications to the heads were just bigger valves (2.14" / 1.81") and springs to match my mild aftermarket "purple" camshaft. The 3600lb car ran 12.90s @ 105mph in the quarter. Eventually I pulled the head and had some quality bowl blending done, but nothing extensive. I had the heads flowed and the result was high 240's cfm peak flow. With the new head work the same set up ran 12.49 @ 108mph. Finally, I bought a set of Edelbrock Performer heads when they became available about 1999-2000. Edelbrock claimed 290 cfm, but testing later exposed that those claims were a bit generous. The Edelbrock heads were more likely flowing in the 270s out of the box. With the Edelbrock heads and a larger solid flat tappet camshaft the car ran a best of 11.9@114mph With a number of aftermarket heads available it's easy to make good power with a big block mopar these days, but sometimes you want to run (or have to run) a stock iron casting, and this is an excellent option for those circumstances. Long live the 906 head!
Steve Dulcich flow tested a set of edelbrock street heads a few years back , and the results matched edelbrock's claims . As far as the factory heads go , muscle motors in Michigan came out with a cnc program for them about 15 years ago that makes 313cfm on the intake side .
Back in the day dc made a plastic kit for bb Mopar heads I got from herb mc and u cut em out and they show u where to cut head I had 30 hrs total with new valve s I swear I gained 50 to 60 up not bad and then the kit was 13 bucks. On set 906heads herb would hook u up
Back in the day ported a LOT of 906 heads and 915 heads as well. I ruined a few sets like you said getting into the water jacket but lesson learned. I found the roof of the intakes were the most important the floors hardly did anything really for the work involved. The fact is I used to build up the floor a bit jb weld worked find but you had to drill holes so it would stay put but then I would take out the metal on the other side of the port till it broke through then build it up with jb weld. The roof and width of the intake made the big gains and like you said with the guides being trimmed and the exhaust seats and raising the floor make good gains. Then I used oversized valves intake and exhaust all that and making sure the valves were un shrouded real well made those 906 heads pretty respectable. But it was a LOT of work to do. 312 .590 solid lift cam 11:3.1 compression everything else you would expect intake headers etc.. 68 Road Runner 4 speed 10.80s @ 130 MPH 3650 lbs with me in it. Went 10.71 once was never able to repeat it drove it to work everyday those were the days.
Mopar Performance had porting templates for the 906 heads. They specifically said not to touch the short side radius at all. Building up the floor probably helped a lot.
If you port those heads using Mopar Performance porting templates and 2,19” and 1.82 back cut valves, set static compression at 9.5-1, use a MP .509/292 hydraulic cam, install a windage tray and block off the carb heat crossovers along with a Holley street dominator intake with a 0-3310 Holley 750 and the right size headers, which I don’t remember the size of, that 440 will make 521HP! If you go nuts, you might end up losing port velocity and hurt your performance in the process!
I have a similar 440, same .509" cam and the iron heads have been ported with MP templates with stock size valves. Torker 2 intake, 1 3/4" headers and 750 holley dp. Feels like it has all of 500hp. 3700lbs 66 Coronet runs 11.90s all day long.
That's roughly a 25% flow improvement over a stock 906. Better than I expected. I've seen numbers around 215-230 from a stock head, down around 200 with a bad valve job.
Great video being that I recently sent my 1967 915 closed chamber BBM heads off to be CNC ported (same ports as 906). The gentleman that runs the place told me what they’ll flow and sounds like pretty much what you got. Who knows though, might not even be the same place, could be one of the many cast iron Mopar CNC head porting services out there lol. Thanks!
I have probably ported at least 25 sets of 906 heads starting in 1977 currently doing an Edelbrock pair as we speak...Doing these heads for Super Stock is challenging with a 2.08 intake valve it is hard to stay away from the water jackets...we used to run the piston above the deck on the bracket engines to use the quench area "open Chamber" for a good 13-14.0 compression ratio. A Super Stock head w/2.08 valve flows over 300 C.F.M. if you're into flow bench racing.
Don't get me wrong. Why is the 68 head better than the 67 closed chamber head ? Also. The 906 head just looks even with no difference from the exhaust side of the combustion chamber to the intake. 906 has a big chamber. You would think it would ping or have pre ignition problems.
nice info Eric, Being a mopar big block guy I remeber porting my first set of 452 castings that were really bad about 30 years ago. they went 260cfm with the old 3/8 stem etc etc. a few years later just for shits and gigglesI ported another set of 452. this time I kept the std size valves. with just the bowl , back cut and seat it went 268.8 cfm. taught me a lot about shrouding. not all heads will respond to larger valves. just my 2 cents. I wish I could turn back time knowing now what to do.lol. keep up the work.
Very good Eric. I think your customers heads came out pretty good. The valve job is reversed, should have had the radius on the exhaust and a 5 or 6 angle on the intake with a back cut as you said. Thanks for sharing. Take care, Ed.
MHO here ... I helped design the pistons that Carfarmer mentions with KB chief engineer john Erb and others such as TMS propane. Prior to getting off the shelf pistons we either welded up the chambers or used custom pistons. And due to the cost of custom forged pistons we did a lot of strokers. WE also did a lot of using 67 915 heads which did not have the open chamber, still no factory head and the Edelbrocks and similar do not have a good modern combustion chamber GAS I am not saying open chambers cannot make good horsepower on Chevron Custom Supreme, SUNOCO or race gas but this is usually past the torque peak like Super Stock For street HD or towing a quench chamber and tight quench makes a big difference How much? With a cam without a lot of overlap EGT can drop 700 degrees,
Would you happen to be a member on the FABO forum by chance? There is a member on there who mentioned the same about working with KB on the special pistons with the raised quench pad, initially for city bus applications. He hasn't been active on there in a while though...?
I have a 1970 Mopar Performance engine book and it does say to radius both the intake and exhaust valve seats. In 1977, the 1.81" exhaust valves weren't available off the shelf, but the 2.14" intake valves were. The 1.88" Max Wedge exhaust valves were available, so we cut down the 1.88" valves to 1.83", with a 0.100" margin. The valves we used back then, had standard stem diameter and single groove valve locks were important to use with solid lifters.
Great video. Thanks for doing this one. I learn from every video, I happen to be a Mopar guy but I appreciate all brands and I think one can learn from all the different heads out there. Thanks for sharing.
Actually, there is a benefit to having the flat areas (where there "SHOULD" be a quench area, LOL) machined: someone (KB?) does or at least did sell pistons to fit up into that area to make quench, but guys never got good results with cast chambers because they were always slightly different depths - if one piston had a good clearance, another was a mile away, and yet another might be waaayy too close for comfort. Funny there's no back cut on those intakes. A little surprised; those heads don't look like they were really trying to cut corners on the job BTW, I wonder how that bowl shape compares to the shape of the old Direct Connection templates... FWIW, that casting family (2843906 is '68-70; the later ones were pretty similar) universally seem to stall around .420-450" in stock condition Wondering if the short side radius is better on that for 40 Source head
I agree , the few sets of open chamber mopar heads I have played with for friends I have equalized the depth of the open part of the chamber for use with a KB step head piston and for a set of custom Diamonds I had made. I had an NOs set of 452 castings that I bought back in the late 80's , Paul Rossi street fighters , the open part of the chambers varied in depth from .110 at the ends of the heads to .130 in the middle . I had a program done up to run on a proto track bridgeport I use at work to do the chambers all the same before having them surfaced to get a final uniform depth for the clearance to the step on the piston.
The reason most porters smooth the chamber in cast iron heads is to reduce carbon buildup within the chamber . Carbon won't stick to a smooth chamber like it will on a rough one .
Good video Eric,Someone went to the effort to do a CNC program for those...they must have the demand.... I ported a set of those 906's nearly 30 years ago, i remember getting 310 cfm on inlets at around .700' lift..3/8" stems.... also a set of small block W2's, also 310 cfm at .700'...for the same engine builder.... long time ago...
It's not worth it to dump $1000 in the old heads for porting. By the time you factor in the rest of the machine work and new valves just go with a set of E Street Eddy heads. Or 440source
There was still a lot of material to take out.. Funny how they don't do hand finishing on these things. That job wasn't cheap for the customer only to get a half way there. And for the guide job, it really depends on the valve how much it wobbles. If the valve head is heavy and the valve rides on a near horizontal angle the guide needs to be longer, but if the valve is light and vertical, the guide can be shortened quite a bit. I had one engine that had done a full rally season with half the guide length and still ran great. It had titanium valve heads, so all the weight was on the stem.
What MOPAR has needed for a long time (and I might as well add Pontiac to this also), is a nice aftermarket canted valve cylinder head, that puts it on the same level as the big block Chevy's and Ford's.
Cast iron is how I learned how to Port yeah it's time-consuming I know but at the time not everybody out had a CNC machine and we're pumping out a high volume for Circle Track
On the ex we left them long to keep heat off the valve and not super narrow seats on the trucks. Excellent advice on the radius ex seat, back cut etc Now mopar does not like overlap (the factory Magnum cam is terrible) our Municipal Bus cam was 192 at .050 and Mike Jones Mopar "motorhome" is the Best at this duration from memory 254@,006, 204 @.050 ,305 lift at the cam and really fat at .200 The trick for life is to keep the valves on the seats
An old cast porting vid on the old mopar heads. I doesn't get any better than that. The Promaxx 240 CNC mopar head for the RB should be interesting vs the Trickflow 240.
It's really too bad Mopar didn't carry on with the Max Wedge port head after '64. Once the Hemi came along they didn't want the wedge stealing its thunder IMO.
The valve and port orientation on the BBM wedge engines held them back no matter how big the ports were. They tried running Max Wedge heads in NASCAR before the Hemi and they still couldn't keep up with the competition. There was a program started to reintroduce the Max Wedge in the early 1970s for drag racing but it never saw the light of day.
Keith Black makes some pistons that have a pop up that goes into the recessed part of the chamber. It acts as a quench pad because those heads don't have a quench area. That's probably why they cut them all equal.
I agree with the positive comments below .. I think it would be to show the port area of both of your flow results in the last column of your flow charts. Not a big difference but perhaps a little discussion and comparison. I think you tenured your remarks a bit not to dis the shop who ported that, having said that, I think it could have been cleaner without comprising the water jackets
About the guides, check out some spin tron videos, the stim will actually move alot while in operation, especially at high RPM. And extra short guides make it worse!
I’m a Chrysler guy. I don’t believe that the guys that opened these heads up did their best. For decades, I have seen flow numbers on 906/915/452 heads flow around 290-305cfm@ 0.600” without CNC. It looks like a lot was left on the table here.
Eric, you did a flow test on a 440 Source head last year and it had similar numbers to this head with the exception of .500 lift and they were just a little below these numbers, 262.2 where here is 275.6. Will an intake back cut make up that difference? I've heard you talk about how the back cut intake helps but I don't know what it would do on the 440 Source heads. I am loking to run a set on my stock bore & stroke 383 and not concerned with anything over .500 lift as the cam I'm planning, Crower HDP271 gets to just almost .500. Thanks and great stuff.
Something to think about on the " bad / incomplete " mods to the head ( like no back cut on the intake ) . Does the porting company offer different levels of prep and did the customer get a lower level of prep?
Back in 85 .650 was max lift on roller cams the turbulence you see may have been the reason no cam taller was available that was always a problem no one could tell you that was there
There were several basic casting designs for the ports, the early -66 and prior 516 heads: sucked. The 1967 only 915 had a smaller chamber and the 906 port design, these are commonly considered the "best" normal port cast iron heads. The 68-69 906 heads had the open chamber and the same "good" port. After 1970, they had a bunch of numbers: 902, 452, etc, but they were basically all the same ports, with other differences like seat hardening. There were also, for the 452 heads at least, some that had added steam holes for police cars and trucks and RV's and such. I have a couple pairs of these.
The stock heads, the 452 types I've flowed typically were about 220-230cfm stock. A good valve job and 10-15min per bowl gets you 240-245, which is a nice payoff IMO.
@@EchoSixMike only issue there is a good valve job is around 300 bucks then if you don’t have the carbide burrs to work on the heads in total will be a few hundred bucks then a few hours of time total doing the work and that isn’t including setup of the springs/locks/retainers/ and height for everything you are in it almost what a 440 source head cost to buy and even then the 440 source head flows 260 out of the box and can be ported much easier if you even want to go that route… I know this because I spent 1000 bucks on a set of 902s a couple years back
@@jeredfowler7194 All true, although valve job and shop work pricing is a large regional variation. Sometimes you have to run iron heads, although that's mostly a small block dirt track type of thing. The Source heads are a godsend for the FAST class guys who need to run stuff that looks stock, I would go for the Eddie RPM's, the Promaxx eddie copies or save up and get the Trick Flow heads if I was aiming for the most power/buck ratio. The one nice part about the stock heads is that you know they bolt right up, most everything else needs some level of massaging.
The decks on those heads are a little ugly, considering how large the chambers are to begin with he should have just had it decked till the rust pits were gone. Eric it would have been nice to see the difference in flow with a back cut valve on the intake, did the owner of these ask you to tweak them ? The depth of the chambers on as cast heads are all over the place, that's the bigger reason to cut the open part of the chamber , and the chamber in general , is to get the cc's of the chamber closer to equal.
I just emailed him asking him to pretty please do the back cut on the valves, and shave the guides. Hope he agrees, he mentioned 8cfm gain at low lift just from the back cut!
A long time I had a couple of dodge cars . A 68 charger that I installed a 426 marine engine and later on a 66 Belvedere with a 440 , 4 speed car . After a while I decided that the wedge motor did not have enough cylinder heads to make the hp I wanted . I not sure if anyone ever did . May be Indy did or someone make a head that will support hp and do it to over 6500 and not lay over . The wedge motor was just a torque motor . I lost interest in the Mopar because I like to spin up a engine and have it not lay over . I never had a hemi
@@notinterested8397 forbbodiesonly 😋 and not directly to Transylvania, first they'll go to a gentleman who will port a stock iron intake, and match it to the heads.
some running comments Valves 11/32 or 516 valves, you can get a better than stock valve for less money than stock replacement and you are going to do the guides anyway arn't you? Now the best HD valves for towing, truck, motothome are the440 motorhome valves SILXB materiel on the intakes with Hard Chrome (copper-nickel grind- chrome) stems Exhausts are Nickel heads like Inconel Stock valves may have a flash chrome "chrome"' stem s which quickly wears through and is not for wear in the first place, it's for non rust shelf life. I OD hone all valves and 50 year old valves are not going to pass The previous hot tip to use the Direct Connection 2.14 intakes and 1.81 exhaust can still get you better seats but they are still heavy and MOPAR hates heavy. PS on Trucks we used to take these DC valves and cut a 30 degree seat on the intakes with a .450 lift cam I did not try radius seat but others did not recommend on intake. Valves will be sunk on old heads and MOPAR does not like sunk valves so put in some HD Durabond sintered seats And after all this you could have bought some new Aluminum heads I have 3 sets of 915's all ready for valve jobs that I will never get my money out unless I find a resto 67 GTX project. back to the video
The claim has been that 452 head flows more then 906, well have been shown hand ported reaching 300 cfm. If i knew who cnc those heads , i still have nive set of 906 with 2.14 Ferrera valves with a back cut already
Head flow is just one aspect of performance. Bench talk bla bla. Rod to stroke ratio has huge affect on performance too. And Mopar big blocks have a rod to stroke ratio to kill for! Dont believe? Just look at the classic big block shootout Landy and Kasse and that chevy guy. Mopar had the least cubes and slayed both ford and chevy Merciless! Eat your hearts out. Smile😊
Tell me how a 440 with these heads run as good as they do. These heads suck ass, but I've seen plenty bb Mopar with unported cast heads run like a bat out of hell. Add the weight of everything and it gets worse. They are built like a tractor. But damn they run good for a bunch of heavy junk.
I think this shows pretty well that the 440Source heads are basically aluminum copies of factory heads with minor improvements. Also those saying the factory heads have low flow for the cubes they fed, that is true but keep in mind the BBM was first released in 1958. The common big blocks from Ford (385 series) and Chevy (Mark IV) came later and had the benefit of better knowledge about flow. Also the first BBM engines were small displacement, 350-361 initially with the raised-deck 413 soon after in 1959.
The source head is a chinese copy of the ebrock RPM 84cc head made to look like a stock cast iron casting on the outside, they could have picked a better head to copy after seeing how close in flow this 906 is to a supposed cnc's set.
@@dartgts383 it's not a copy of the Edelbrock RPM, that head is its own design and actually flows better than the 440Source stealth.
@@mopartron3030 sorry it is , look at the chambers , EXACT shape , does not look like a 915 closed chamber shape , Modern ran their RPM CNC program on it and it flowed exactly the same as the cnc'd RPM. source even posted it in an online forum a number of years ago.
@@dartgts383 You need to look at as-cast flow numbers to get a fair comparison. Engine Masters did a 440 dyno test where they compared stock iron vs stealth vs RPM vs trick flow (all unported) and with each change their mild 440 picked up 15-25 hp. Not really worth arguing anyway you can get overlapping results from each type of head depending on the work done.
@@mopartron3030 You don't need to tell be about as cast numbers , when the Stealth was first released the flow numbers CLAIMED were not the flow numbers head porters whose benches I trust showed. The chinese have no problem trying to copy another companies intellectual property , they just do a half assed job at it .
Videos where something stock or not quite ideal sees significant improvement with some well-thought-out work, seems to grab my attention. Well done.
I do not blame you on Porting Cast Iron. I Hate porting on Cast Iron. Aluminum I would do all day long with no issues. When I worked at Racers Edge AZ I use to do a lot of the Porting, Seat to Bowl Blending and cumbustion chamber bleanding as well after the CNC finnished them up.
ive found really nice stones work better on cast
Thank you, I am a Mopar guy and I appreciate all the data.
Some people wouldn't even let a Mopar head touch their flow bench. One thing about Mopar fans is that they do more with less. We may be down on hp but our suspension is tricked out. It is just personal taste, it's your money, spend it on what you want. Thanks for the flow test and pointing out what works and doesn't, and why.
Thanks for the Mopar content !!
Eric, seeing what you do and what i always wanted to do makes me really want to get back into getting my hands dirty. Up here in northern New York there isn't alot of this kind of work going on. I am a Mopar guy but i enjoy all of them. I guess i'm going to go see an old friend that has his own transmission business to see what what kind of work is out there. Just remember this, i watch your videos because i remember the old Engine Masters Challenge and you did very well against the best engine builders ever. In short, i watch you for knowledge and inspiration; your video's may not make any money for you but they mean alot to me. Keep it up and maybe sometime soon i'll be ordering parts through you instead of Summit. I have a horsepower addiction that needs to be fed!
I’ve only spoken to him on the phone, but Porter Racing Heads in Burlington VT is an excellent mostly Mopar shop. Dwayne Porter is a wealth of knowledge on porting Mopar heads, cam design, dyno testing, class drag racing etc.
Very cool video. I'm only aware of one company that has a CNC program for 906 heads and while I've heard good things, its nice to see some independent testing. I'm personally impressed! Going back 20+ years ago, I had a unported set of 906s on a rebuilt 440. The modifications to the heads were just bigger valves (2.14" / 1.81") and springs to match my mild aftermarket "purple" camshaft. The 3600lb car ran 12.90s @ 105mph in the quarter. Eventually I pulled the head and had some quality bowl blending done, but nothing extensive. I had the heads flowed and the result was high 240's cfm peak flow. With the new head work the same set up ran 12.49 @ 108mph. Finally, I bought a set of Edelbrock Performer heads when they became available about 1999-2000. Edelbrock claimed 290 cfm, but testing later exposed that those claims were a bit generous. The Edelbrock heads were more likely flowing in the 270s out of the box. With the Edelbrock heads and a larger solid flat tappet camshaft the car ran a best of 11.9@114mph
With a number of aftermarket heads available it's easy to make good power with a big block mopar these days, but sometimes you want to run (or have to run) a stock iron casting, and this is an excellent option for those circumstances. Long live the 906 head!
Steve Dulcich flow tested a set of edelbrock street heads a few years back , and the results matched edelbrock's claims . As far as the factory heads go , muscle motors in Michigan came out with a cnc program for them about 15 years ago that makes 313cfm on the intake side .
Back in the day dc made a plastic kit for bb Mopar heads I got from herb mc and u cut em out and they show u where to cut head I had 30 hrs total with new valve s I swear I gained 50 to 60 up not bad and then the kit was 13 bucks. On set 906heads herb would hook u up
@@vincentrachelsdad-yr1kryes, the old DC porting templates
Remember seeing an advertisement for the templates in motor trend magazine, showed where NOT to cut more importantly
Back in the day ported a LOT of 906 heads and 915 heads as well. I ruined a few sets like you said getting into the water jacket but lesson learned. I found the roof of the intakes were the most important the floors hardly did anything really for the work involved. The fact is I used to build up the floor a bit jb weld worked find but you had to drill holes so it would stay put but then I would take out the metal on the other side of the port till it broke through then build it up with jb weld. The roof and width of the intake made the big gains and like you said with the guides being trimmed and the exhaust seats and raising the floor make good gains. Then I used oversized valves intake and exhaust all that and making sure the valves were un shrouded real well made those 906 heads pretty respectable. But it was a LOT of work to do. 312 .590 solid lift cam 11:3.1 compression everything else you would expect intake headers etc.. 68 Road Runner 4 speed 10.80s @ 130 MPH 3650 lbs with me in it. Went 10.71 once was never able to repeat it drove it to work everyday those were the days.
Mopar Performance had porting templates for the 906 heads. They specifically said not to touch the short side radius at all. Building up the floor probably helped a lot.
If you port those heads using Mopar Performance porting templates and 2,19” and 1.82 back cut valves, set static compression at 9.5-1, use a MP .509/292 hydraulic cam, install a windage tray and block off the carb heat crossovers along with a Holley street dominator intake with a 0-3310 Holley 750 and the right size headers, which I don’t remember the size of, that 440 will make 521HP! If you go nuts, you might end up losing port velocity and hurt your performance in the process!
1 7/8" primary tube header diameter
I have a similar 440, same .509" cam and the iron heads have been ported with MP templates with stock size valves. Torker 2 intake, 1 3/4" headers and 750 holley dp. Feels like it has all of 500hp. 3700lbs 66 Coronet runs 11.90s all day long.
That's roughly a 25% flow improvement over a stock 906. Better than I expected. I've seen numbers around 215-230 from a stock head, down around 200 with a bad valve job.
Great video being that I recently sent my 1967 915 closed chamber BBM heads off to be CNC ported (same ports as 906). The gentleman that runs the place told me what they’ll flow and sounds like pretty much what you got. Who knows though, might not even be the same place, could be one of the many cast iron Mopar CNC head porting services out there lol. Thanks!
Where did you send them?
where did you send them ?
I have probably ported at least 25 sets of 906 heads starting in 1977 currently doing an Edelbrock pair as we speak...Doing these heads for Super Stock is challenging with a 2.08 intake valve it is hard to stay away from the water jackets...we used to run the piston above the deck on the bracket engines to use the quench area "open Chamber" for a good 13-14.0 compression ratio. A Super Stock head w/2.08 valve flows over 300 C.F.M. if you're into flow bench racing.
Don't get me wrong. Why is the 68 head better than the 67 closed chamber head ?
Also. The 906 head just looks even with no difference from the exhaust side of the combustion chamber to the intake.
906 has a big chamber. You would think it would ping or have pre ignition problems.
915 Heads are harder to find...@@jesse75
nice info Eric,
Being a mopar big block guy I remeber porting my first set of 452 castings that were really bad about 30 years ago. they went 260cfm with the old 3/8 stem etc etc. a few years later just for shits and gigglesI ported another set of 452. this time I kept the std size valves. with just the bowl , back cut and seat it went 268.8 cfm. taught me a lot about shrouding. not all heads will respond to larger valves. just my 2 cents. I wish I could turn back time knowing now what to do.lol. keep up the work.
Thanks Eric for a very honest, fair minded review. Love to see how you would rate the 270 Trickflow Mopar head.
Very good Eric.
I think your customers heads came out pretty good.
The valve job is reversed, should have had the radius on the exhaust and a 5 or 6 angle on the intake with a back cut as you said.
Thanks for sharing.
Take care, Ed.
MHO here ... I helped design the pistons that Carfarmer mentions with KB chief engineer john Erb and others such as TMS propane. Prior to getting off the shelf pistons we either welded up the chambers or used custom pistons. And due to the cost of custom forged pistons we did a lot of strokers. WE also did a lot of using 67 915 heads which did not have the open chamber, still no factory head and the Edelbrocks and similar do not have a good modern combustion chamber
GAS I am not saying open chambers cannot make good horsepower on Chevron Custom Supreme, SUNOCO or race gas but this is usually past the torque peak like Super Stock
For street HD or towing a quench chamber and tight quench makes a big difference
How much? With a cam without a lot of overlap EGT can drop 700 degrees,
Would you happen to be a member on the FABO forum by chance? There is a member on there who mentioned the same about working with KB on the special pistons with the raised quench pad, initially for city bus applications. He hasn't been active on there in a while though...?
@@mopartron3030 FABO Abodies forum years ago
I have a 1970 Mopar Performance engine book and it does say to radius both the intake and exhaust valve seats. In 1977, the 1.81" exhaust valves weren't available off the shelf, but the 2.14" intake valves were. The 1.88" Max Wedge exhaust valves were available, so we cut down the 1.88" valves to 1.83", with a 0.100" margin. The valves we used back then, had standard stem diameter and single groove valve locks were important to use with solid lifters.
That might have been the thinking back then.
Nice video Eric. Those heads are pretty impressive in the overall.
Great video. Thanks for doing this one. I learn from every video, I happen to be a Mopar guy but I appreciate all brands and I think one can learn from all the different heads out there. Thanks for sharing.
Thanks for answering my valve guide question on my 4 valve per cylinder head.
Very nice work on those 906's.... Good Job !
I was told by an older friend that the guide also helps to take heat away from the valve.
Actually, there is a benefit to having the flat areas (where there "SHOULD" be a quench area, LOL) machined: someone (KB?) does or at least did sell pistons to fit up into that area to make quench, but guys never got good results with cast chambers because they were always slightly different depths - if one piston had a good clearance, another was a mile away, and yet another might be waaayy too close for comfort.
Funny there's no back cut on those intakes. A little surprised; those heads don't look like they were really trying to cut corners on the job
BTW, I wonder how that bowl shape compares to the shape of the old Direct Connection templates...
FWIW, that casting family (2843906 is '68-70; the later ones were pretty similar) universally seem to stall around .420-450" in stock condition
Wondering if the short side radius is better on that for 40 Source head
Yes, KB ‘quench dome’
@@rong4189 bingo!
@@causeimbatmaaan not without the funky pistons...
I agree , the few sets of open chamber mopar heads I have played with for friends I have equalized the depth of the open part of the chamber for use with a KB step head piston and for a set of custom Diamonds I had made. I had an NOs set of 452 castings that I bought back in the late 80's , Paul Rossi street fighters , the open part of the chambers varied in depth from .110 at the ends of the heads to .130 in the middle . I had a program done up to run on a proto track bridgeport I use at work to do the chambers all the same before having them surfaced to get a final uniform depth for the clearance to the step on the piston.
The reason most porters smooth the chamber in cast iron heads is to reduce carbon buildup within the chamber . Carbon won't stick to a smooth chamber like it will on a rough one .
That was kind of interesting. Thanks for the content. Still wishing your success.
If it ain’t Mopar , it’s no car.
Bowtie gaptizing since 1957
EWWW lol Mopar....
Good video Eric,Someone went to the effort to do a CNC program for those...they must have the demand.... I ported a set of those 906's nearly 30 years ago, i remember getting 310 cfm on inlets at around .700' lift..3/8" stems.... also a set of small block W2's, also 310 cfm at .700'...for the same engine builder.... long time ago...
That's awesome must have cost an arm and a leg for the cnc porting.
You should see the shipping bill! They're going to Transylvania.
It's not worth it to dump $1000 in the old heads for porting. By the time you factor in the rest of the machine work and new valves just go with a set of E Street Eddy heads. Or 440source
@@mitchellferre1652
Most people are only sinking money into these because of class rules.
There was still a lot of material to take out.. Funny how they don't do hand finishing on these things. That job wasn't cheap for the customer only to get a half way there. And for the guide job, it really depends on the valve how much it wobbles. If the valve head is heavy and the valve rides on a near horizontal angle the guide needs to be longer, but if the valve is light and vertical, the guide can be shortened quite a bit. I had one engine that had done a full rally season with half the guide length and still ran great. It had titanium valve heads, so all the weight was on the stem.
Mopar guys got it rough , low flow numbers for a big block.
Trick Flow makes some of the best heads for Mopar engines.
@@kennywhiddon1497 270"s max wedge ...... awsome job.
What MOPAR has needed for a long time (and I might as well add Pontiac to this also), is a nice aftermarket canted valve cylinder head, that puts it on the same level as the big block Chevy's and Ford's.
Mopar has that it's called a Hemi
@@davepotanko5514 Yes I know, but what I mean is they need something in between an inline wedge and a full Hemi
Cast iron is how I learned how to Port yeah it's time-consuming I know but at the time not everybody out had a CNC machine and we're pumping out a high volume for Circle Track
On the ex we left them long to keep heat off the valve and not super narrow seats on the trucks. Excellent advice on the radius ex seat, back cut etc Now mopar does not like overlap (the factory Magnum cam is terrible) our Municipal Bus cam was 192 at .050 and Mike Jones Mopar "motorhome" is the Best at this duration from memory 254@,006, 204 @.050 ,305 lift at the cam and really fat at .200 The trick for life is to keep the valves on the seats
An old cast porting vid on the old mopar heads. I doesn't get any better than that.
The Promaxx 240 CNC mopar head for the RB should be interesting vs the Trickflow 240.
It's really too bad Mopar didn't carry on with the Max Wedge port head after '64. Once the Hemi came along they didn't want the wedge stealing its thunder IMO.
The valve and port orientation on the BBM wedge engines held them back no matter how big the ports were. They tried running Max Wedge heads in NASCAR before the Hemi and they still couldn't keep up with the competition. There was a program started to reintroduce the Max Wedge in the early 1970s for drag racing but it never saw the light of day.
@@mopartron3030 hemi was the demise of Chrysler
Keith Black makes some pistons that have a pop up that goes into the recessed part of the chamber. It acts as a quench pad because those heads don't have a quench area. That's probably why they cut them all equal.
I agree with the positive comments below .. I think it would be to show the port area of both of your flow results in the last column of your flow charts. Not a big difference but perhaps a little discussion and comparison. I think you tenured your remarks a bit not to dis the shop who ported that, having said that, I think it could have been cleaner without comprising the water jackets
About the guides, check out some spin tron videos, the stim will actually move alot while in operation, especially at high RPM. And extra short guides make it worse!
Those would be some nice heads on a 383 sbc 😉
Work good for a 383 low deck Chrysler or 400 low deck Chrysler
I’m a Chrysler guy. I don’t believe that the guys that opened these heads up did their best. For decades, I have seen flow numbers on 906/915/452 heads flow around 290-305cfm@ 0.600” without CNC. It looks like a lot was left on the table here.
Shadowing and casting flash drive me nuts
I had 915 440 head closed chamber I wondered what thay flowed.
Eric, you did a flow test on a 440 Source head last year and it had similar numbers to this head with the exception of .500 lift and they were just a little below these numbers, 262.2 where here is 275.6. Will an intake back cut make up that difference? I've heard you talk about how the back cut intake helps but I don't know what it would do on the 440 Source heads. I am loking to run a set on my stock bore & stroke 383 and not concerned with anything over .500 lift as the cam I'm planning, Crower HDP271 gets to just almost .500. Thanks and great stuff.
The stock bore for a 440 is 4.320 so your fixture is pretty close.
The intake ports and bowls look to smooth for a carburetorated application?
Thank you for your knowledge 💪🏽 USA 🇺🇸 USA 🇺🇸
Something to think about on the " bad / incomplete " mods to the head ( like no back cut on the intake ) . Does the porting company offer different levels of prep and did the customer get a lower level of prep?
Back in 85 .650 was max lift on roller cams the turbulence you see may have been the reason no cam taller was available that was always a problem no one could tell you that was there
Hey Eric , would you angle mill these to achieve a closed chamber ??
Whats a good length to shoot for on the valve guides?
How many different big block heads did Chrysler make? Seems head flow held the big cubes back!!
There were several basic casting designs for the ports, the early -66 and prior 516 heads: sucked. The 1967 only 915 had a smaller chamber and the 906 port design, these are commonly considered the "best" normal port cast iron heads. The 68-69 906 heads had the open chamber and the same "good" port. After 1970, they had a bunch of numbers: 902, 452, etc, but they were basically all the same ports, with other differences like seat hardening. There were also, for the 452 heads at least, some that had added steam holes for police cars and trucks and RV's and such. I have a couple pairs of these.
The head’s didn’t flow great stock but volume was really small for a 400+ inch engine they were like 210 cc stock unless it was a max wedge head
The stock heads, the 452 types I've flowed typically were about 220-230cfm stock. A good valve job and 10-15min per bowl gets you 240-245, which is a nice payoff IMO.
@@EchoSixMike only issue there is a good valve job is around 300 bucks then if you don’t have the carbide burrs to work on the heads in total will be a few hundred bucks then a few hours of time total doing the work and that isn’t including setup of the springs/locks/retainers/ and height for everything you are in it almost what a 440 source head cost to buy and even then the 440 source head flows 260 out of the box and can be ported much easier if you even want to go that route… I know this because I spent 1000 bucks on a set of 902s a couple years back
@@jeredfowler7194 All true, although valve job and shop work pricing is a large regional variation. Sometimes you have to run iron heads, although that's mostly a small block dirt track type of thing. The Source heads are a godsend for the FAST class guys who need to run stuff that looks stock, I would go for the Eddie RPM's, the Promaxx eddie copies or save up and get the Trick Flow heads if I was aiming for the most power/buck ratio.
The one nice part about the stock heads is that you know they bolt right up, most everything else needs some level of massaging.
The decks on those heads are a little ugly, considering how large the chambers are to begin with he should have just had it decked till the rust pits were gone. Eric it would have been nice to see the difference in flow with a back cut valve on the intake, did the owner of these ask you to tweak them ? The depth of the chambers on as cast heads are all over the place, that's the bigger reason to cut the open part of the chamber , and the chamber in general , is to get the cc's of the chamber closer to equal.
I just emailed him asking him to pretty please do the back cut on the valves, and shave the guides. Hope he agrees, he mentioned 8cfm gain at low lift just from the back cut!
I changed small block dodge valves to 11/32
Did you mention the valve size? Thanks
A long time I had a couple of dodge cars . A 68 charger that I installed a 426 marine engine and later on a 66 Belvedere with a 440 , 4 speed car . After a while I decided that the wedge motor did not have enough cylinder heads to make the hp I wanted . I not sure if anyone ever did . May be Indy did or someone make a head that will support hp and do it to over 6500 and not lay over . The wedge motor was just a torque motor . I lost interest in the Mopar because I like to spin up a engine and have it not lay over . I never had a hemi
What company ports cast iron 906
Any gen 3 Hemi on the Horizon?
Awesome video Eric. The heads look great for what they are.. who did the cnc work ?
KG engines, out of Ohio. I know who's heads they are , and where they are going. (You wouldn't believe me....)
@@notinterested8397 ??
They belong to a member of "for a bodies only", and they are on their way to Transylvania
@@notinterested8397 forbbodiesonly 😋 and not directly to Transylvania, first they'll go to a gentleman who will port a stock iron intake, and match it to the heads.
@@MattVonKlausenburg oops! I'm a member on both, and forgot which side you were on, lol
Who did the cnc job originally?
some running comments Valves 11/32 or 516 valves, you can get a better than stock valve for less money than stock replacement and you are going to do the guides anyway arn't you?
Now the best HD valves for towing, truck, motothome are the440 motorhome valves SILXB materiel on the intakes with Hard Chrome (copper-nickel grind- chrome) stems Exhausts are Nickel heads like Inconel
Stock valves may have a flash chrome "chrome"' stem s which quickly wears through and is not for wear in the first place, it's for non rust shelf life. I OD hone all valves and 50 year old valves are not going to pass
The previous hot tip to use the Direct Connection 2.14 intakes and 1.81 exhaust can still get you better seats but they are still heavy and MOPAR hates heavy.
PS on Trucks we used to take these DC valves and cut a 30 degree seat on the intakes with a .450 lift cam I did not try radius seat but others did not recommend on intake.
Valves will be sunk on old heads and MOPAR does not like sunk valves so put in some HD Durabond sintered seats
And after all this you could have bought some new Aluminum heads
I have 3 sets of 915's all ready for valve jobs that I will never get my money out unless I find a resto 67 GTX project.
back to the video
The claim has been that 452 head flows more then 906, well have been shown hand ported reaching 300 cfm. If i knew who cnc those heads , i still have nive set of 906 with 2.14 Ferrera valves with a back cut already
KG engines, out of Ohio.
Head flow is just one aspect of performance. Bench talk bla bla. Rod to stroke ratio has huge affect on performance too. And Mopar big blocks have a rod to stroke ratio to kill for! Dont believe? Just look at the classic big block shootout Landy and Kasse and that chevy guy. Mopar had the least cubes and slayed both ford and chevy Merciless! Eat your hearts out. Smile😊
w/ 2.14, supose tu be a 300 + .. on fair production steel head.
I'll still take the stealth head over heavy open chamber cast iron.
id at least smooth out where they left it alone
Nature has its ways think about compressing water with air ??? Telodyne water pic has this technology.... 🤔
Hate to say it but if these are not on the dealers floors for sale I don't want to hear it...
Tell me how a 440 with these heads run as good as they do. These heads suck ass, but I've seen plenty bb Mopar with unported cast heads run like a bat out of hell. Add the weight of everything and it gets worse. They are built like a tractor. But damn they run good for a bunch of heavy junk.
Thanks for the Mopar content!