I've ported a few aluminum heads/intakes. The aluminum gets hot and melts, jamming up the bit. The solution is keep spraying it with WD40 to keep it cool. You can unjam a bit the same way-spray it a bunch then use it a little bit and spray some more.
Hey Jeff! Just a tip for cleaning the Aluminium out of the burs is to use concrete or pool cleaner. It's Hydrochloric Acid which eats Aluminum very fast! Just make sure u clean them very well with brake cleaner afterwards. Good luck!
That is one of my favorite parts of my builds. It's long tedious work. But for some reason I just really enjoy it. I kind of get in a zone and the hours fly by. You won't gain a whole lot by just gasket matching the ports. Most of your improvements would come from the bowl areas. On my intake ports I don't go any finer then a 80 grit finish. On my exhaust ports and combustion chambers, I polish them right to a mirror like finish. When porting aluminum heads you need to use some kind of lubricant with the burrs. WD40 works. There is also an actual grinding grease/compound you can get too. I've used and seen many different oil, greases and waxes used. If you don't use something, as you found out, the burrs just get packed with the aluminum shavings.
Looking good Jeff. I use beeswax on the burrs and when I don't have any I use aluminium cutting oil. As some guys said wd40 works too. Another point about the exhaust ports is that you can actually open up the exhaust manifold a little larger than the ports. This helps prevent backflow and the gases still flow out easily. Great job so far, I love your ambition and confidence to try new things. You're an inspiration. 👍
Jeff. Firstly love your videos. Keep it up. Secondly, those carbide bits are mainly for steel, but can be used on aluminum. The trick to keeping carbide bit clean is simple. Candle wax. Every do often. Stop porting and spin the bit in a bit of candle wax. Don't run the tool fast. Justca quick touch and go back to work. You will notice the bit will clean up almost instantly after you start working again.
Always loving your work Jeff. Love that you get stuck in and don't hide your mistakes. When you paint your block, the correct paint is in the 'British Standard' database as B.S. 18C39, with HMG ( Her Majesty's Government ) Glidden number GL31557, and Glidden number name 'Dolphin Blue'. Seeing Nissan/Datsun engines of that era in any other shade or colour upsets my OCD.
I worked in a engine machine shop throughout highschool. Muriatic acid is what is used( pool cleaner) to eat aluminum out of cylinder bores and other surgaces without damage to steel surface. It works on burs and files after porting. Don't heat the bur it will mess with the hardened bur.
Don't forget to blend the valve seats with the runners, pretty simple and removes turbulence at that sharp edge. And for cleaning your carbide tip just grind away at a piece of steel and it will come off.
Nice work Jeff, Porting takes time but i've always felt it's rewarding work. I've heard the tool doesn't clog up if you dip it in automatic transmission oil but I've never tried it. As yo said, the walls dont have to be super smooth...
Hi Jeff - try spraying a little WD40/ Inox etc on the burr before grinding and the alloy will brush off easily with a wire brush or similar - just dress it with the wd 40 now and again and it is much easier to keep clean... Spent a good few hours porting Alfa heads like this. Thanks for the great vids !
Nice video as usual, if you use cutting oil or Wd 40 when drilling alumininium your drills will stay sharper and leave a nicer finish, probably can be used for the die grinder carbide bits too. When milling aluminimium we always use coolant, the milky white cutting oil to keep the bits cool and flush the chips away
Hi Jeff, you may have picked up a burr suitable for cast iron or steel. But like others have said. Keep grinding and use wd 40 (a small container and to dip into) It will eventually clean itself. Also, you did well to use your drill press but mostly we just use a high speed air drill...it offers more flexibity i.e. to tilt over incase the drill wanders off centre. Broken manifold studs we do the same with...never use an electric drill..too heavy and slow rpm. You've had a fair bit of welding done to the head...I gather you had it straightened and pressure tested? Good idea to have it pressure tested after porting. Cheers
I thought I was doing the right thing with the drill press, but you are correct that the bit still wandered more than I would have liked. I may go through then and use the air drill to finish off the water galleries then. Yes the head was welded and re-straightened. Apparently it had been warped and shaved flat previously as the base was flat but the top was warped. The welder re-straightened the whole thing and then it was machined on 3 sides.
Sorry I missed your reply. I posted before that you might want to consider cam tower shims. I think by memory which are stainless shims (0.9mm) that are installed under the towers...something to do about timing chain tension.
Jeff you can get specialty carbide burrs that are designed for aluminium with a more open cutter and anti-clog flute design. If you buy the generic burrs like the ones your using you will have to either coat them liberally in WD40 every minute or so or use wax to stop the burr clogging.
I use engineers marking blue and a scribed. Gives a better line to work to. Basic port matching is such a simple way of improving the breathing of the engine.
Steel burrs clog when using them on aluminum. In the future if you get a burr for aluminium it will take half the effort and time. But make sure long sleeves and face shield are used and cover your shoes cause the shavings that fly out make some NASTY splinters.
Cast aluminum alloys can be muddy. Best tip for you to keep your burrs clean is WD40 often while working. Don't let it build up at all in the tool. Sandpaper rolls are affectionately known as Tootsie rolls after the candy namesake.Best of luck
Some of the best gains on any head are to be had in and around the valve seats, including the valves themselves. This is by far the most restrictive area. The potential flow here ranges from zero ( valve closed ) to whatever your head can achieve at full valve lift . This will vary from head to head but will always be less than the other areas of the port due to the restrictive nature of the valve guide boss, valve guide and valve stem/ back . Any gains here however minor they may seem will really improve overall flow , especially a low valve lift. This is really useful on any engine particularly a road / street one like you’re building. I’d highly recommend talking to a good local machine shop about cutting three angle valve seats and reducing your valve seat to around 0.070 inches. This is fairly inexpensive . Also good quality valves with waisted stems and a flatter back profile . Or depending on the quality of the oe valve you could modify these to some degree. Bullet nosed valve guides are a good idea too. On the exhaust , it’s about reducing pumping losses so a good radius on the edge of the valve face can aid reverse flow when combined with the other mods . I hope I’m not teaching my granny to suck eggs here ! but these mods are relatively inexpensive and really enhance your engine package . Keep up the good work 🏎🚀
I have gone similar (or further) than that on the 911 engine with 6 angle valve seats, etc. I am just looking at lapping the existing valves in this situation. It is a rabbit hole, that is easy to disappear down, and I am trying to resist. Which is why I only got the machinist to go as far as he has.
Ryan McNeill also don't forget the backside of the seat in the bowl area. I'd argue that's actually the FIRST place to clean up, as it's a huge ridge on factory seats and also gets you the some of the much needed bowl area to make these heads shine.
Good point Jeff , I’ve fallen down that hole myself a few times! Nathan , 100% correct . I’m planning on doing a Rover K Series head soon and will pay particular attention to that.
Never been a fan of lapping with the 'newer' type engines...I didn't have to being a cylinder head machinist. There's a theory that heat expansion on valve seat differs to that of the valve and therefore you don't get a good seal. Are you replacing the guides as well?
No. I am keeping the same valves, guides, etc, so the exact same parts are going back in the same spot. I got the machinist to have a look at them and he was happy with them, so hopefully they don't need much to keep them good.
Just to add Jeff. You might be up for some cam tower shims pending how much has been machined off the head. An engine that old...could've been apart 2 twice before. Cheers
This is tedious work, but definitely gets results, especially matching manifold to head. My wost mistake was guessing when i had the head planed; the engine ran bloody well but i had to beat it with a stick to make it stop, it was dieseling so badly; head off again and some measuring with a burette (like I should have done to start with) found I'd given it a compression ratio of about 13:1!
yeah thats about 20 thou in old timers language so not too radical, but it does pay to measure the chambers so a) you know your exact cr and b) you can even them up (if you have worked the chambers).
racketman2u well with the p90 and flat tops he'd have to shave a TON to get into that realm. ...now, my flat top MN47 that I'm running a turbo on.... That's another story ;-)
The the two Peter Brocks are also linked by the Daytona coupe car. The American Peter Brock was the designer of it for Carol Shelby back in the later 60s. The Australian Peter Brock died in a Daytona reproduction he was driving.
did you get a 3 angel valve job helps heps, on the vw golf the flywheel is easy to lighten 2 kg then balence with crank, then wieght the rods and pistons lighten them as set´s and get them within 2grams then you have what is called blueprinted. getting the rods and pistons done is alot off work but pays off big time in the end regards Sören
Small tip Jeff small tooth cutters can be cleaned up with some scrap steel to grind out the alloy trapped in the teeth 😊 Alloy burs have bigger agressive teeth so they don't clog with alloy. Your one is for steel 😊
Once you get that burr cleaned up, use WD40 while using it to keep the aluminum (or aluminium) from clogging. WD40 has also helped me clean the burr up after clogging it as well.
Awesome work on the porting! The Achilles heal of the Z is the head. All the time and work will pay off. Are you doing new rockers? One thing I had done is have the existing rockers resurfaced.
Home Built By Jeff right on, I had read awhile back that when changing the cam it is sometimes good to resurface or replace. I’ll have to dig for it. Changing bore size at all?
Home Built By Jeff awesome! Flat tops for the win! Our engines will be similar. I have the p79 head though so I have to do a few extra mods, is yours p90?
Hey Jeff, i seem to remember that the camshaft towers should never be removed from the head as they are bolted on and then line bored. Therefore impossible to line up if removed. I had to bin a Datsun 1600 head because of this, hopefully the 240 is different? You might like to just triple check this.
I heard you weren't supposed to remove them either, but the machinist took them off. As the head has been shaved, I need to put shims under them anyway which is a common mod. So there must e a way to do it. The engine shop is the go to for Datsun rally engines, so he knows what he is doing. I will ask when I go to put it back together.
Martin Armstrong it's not that big of a deal. You should number them ideally, and before you torque them down fully install the cam and ensure it rotates smoothly. Making sure to rotate the cam as you torque the towers down will keep them centered properly, just take small torque steps. Having them out of order can make it impossible for them to ever line up though.
Yes , number the cam towers to be on the safe side. They also have dowel locators so taking them off and on is ok. Mixing cam towers with other cylinders can be difficult.
After spending some time at Performance Developments, working on a MUCH more expensive engine, I wasn't as worried working on this. Just taking my time and being careful.
Get yourself a product called Boelube made by Orelube Corp. It is a machinist paste that keeps the flutes of a double cut burr from getting clogged up with aluminum..
I've widened the center bore of plenty of wheels to make them fit something else. WD40 and cutting fluid is your friend in situations like these. Also, think that may be a steel bit =)
You use candlewax or WD-40 as a lubricant when using sandpaper or any sort of cutting mechanism on aluminium otherwise the aluminium will blind to the tungsten carbide Teeth or the sandpaper grit
I haven't read through all the comments, and I'm only up to 7:30 on the video so far. I also know this video is also 9 months in the past. I found the series a few days ago and I'm catching up. Two other types of holes you need to pay attention to are the oil supply holes sending oil from the block up to the head (oil pressure for the cam and valve train) and oil return holes from the top of the cylinder head that drain the oil coming out of the cam (L28 cams had internal oiling, L24 cams used an external spray bar bolted to the side of the cam towers). Identifying the oil supply holes can be done with this diagram: forums.hybridz.org/topic/115160-l6-cooling-system-diagrams/ You should be able to locate return holes by shining light up through the crank case area and noting the illuminated holes in the block gasket surface that should also correspond to the drain holes from the valve train area.
How about the 2 dowel pin holes? Its been a while since i've had my head off. Did nissan put them on 2 head bolt holes or did they have their own hole?
Please paint the engine when you're done.. I want to have a video on painting the engine by you jeff! I'm kinda 50/50 if i'm going to paint my V4 engine.
T Hyatt Clearly you have no idea what you are talking about. These head castings have a series of ( dimples ) along the face as machining indicators to gauge the minimum thickness of the head. L series heads when machined down affects the timing chain geometry and the chain tensioner but it’s easy to just blame everything on the machinist hey.
T Hyatt I guess by the term “ keep wrenchin “ you are murican and can’t handle being wrong but hey bud it’s ok. I understand now you only have experience in pushrod V8 heartbeat of god bless Murcia technology. It’s funny but hard sometimes as a pro to watch these amateur hour guys who have never done it before , teach the masses on RUclips. Sorry Jeff but it is clear you struggle with knowledge on these engines and you should just leave this stuff to the experts.
nice work . spray lots of wd40 to stop alloy going everywhere and tool clogging now don't touch the intake ports any more , the big thing is the exhaust ports press out the exhaust guides .cut 10mm off and round off end cut the exhaust guide boss at about 45deg angle and shape to get the air around the guide cc the head and get comp ratio right . 72 cam = 10 to 1 . 76 cam 11 to 1 spend money on a good long branch tube headers [ bigger is not better ] look at my you tubes
Not sure if I can be bothered pressing out the guides, but I will look at smoothing out the exhaust ports more. I am not going to be going crazy on this engine. It is just going to be a warm street engine. I have triple OER carbs from Stewart Wilkins so it should be nice, but just not nuts.
OK .just shape down the sides of the guide boss with the guide in that 90 deg boss is the biggest restriction to air flow you will have good air flow in and bad flow out .exhaust flow needs to be about 75% of the intake at WOT you will hear the exhaust reversion out the carbys i hope this helps
Port matching is a 70s gimmick, today we step port to resist reversion. Put a 1-2mm chamfer on the inlets and the same on the exhaust manifold. Better still the exhaust manifold bias higher on the head so the sonic reversion can't smash back into the head.
Jeff, next time you're doing some drilling like this, use some Rocol Cleancut for better results(reference your comment around 9:20). And also your drill bits will stay sharper for longer! www.itwpf.com.au/rocol/rtd-cleancut/
Really nice work Jeff, I did similar in the Ford Endura engine I'm rebuilding to my 98' Ford Ka, besides the porting I also cleaned up a little the combustion chamber. It REALLY took a lot of time, but the satisfaction later pays for it.. :D The video is not released in my channel yet, but here is a picture of the work done in the chambers: instagram.com/p/BfGG-goDHCw/ And a picture of how it was originally: imgur.com/Mw191ig About the gasket, it might be used in other versions of the engine/head, then it has more holes than you need, for the Endura engine was the same case. Cheers, Paulo
Home Built By Jeff they made two variants of gasket. Yours looks right for the later p90 head. And for mixed engines using older blocks and newer heads, you generally gasket for the head not the block. That said, I've seen both ways run on street engines... (In other words, don't lose sleep over it)
Jeff, I really like your work ethic and the knowlege that put across, but could you please cut down on the "err's" and "errms" in your episodes. No other youtuber, that I watch, can surpass you in the amount of them.
I am fine when I have time to stop and think about it, but I usually just talk on the fly, so that is why I can't string a coherent sentence together. It is a struggle to get the work done and talk. If I stopped and made up a script each time I would get nothing done. Catch 22.
I've ported a few aluminum heads/intakes. The aluminum gets hot and melts, jamming up the bit. The solution is keep spraying it with WD40 to keep it cool. You can unjam a bit the same way-spray it a bunch then use it a little bit and spray some more.
I remember spending many hours on doing this to my head. Well worth it. Helps flow a bit more air through the engine
Hey Jeff! Just a tip for cleaning the Aluminium out of the burs is to use concrete or pool cleaner. It's Hydrochloric Acid which eats Aluminum very fast! Just make sure u clean them very well with brake cleaner afterwards. Good luck!
That is one of my favorite parts of my builds. It's long tedious work. But for some reason I just really enjoy it. I kind of get in a zone and the hours fly by.
You won't gain a whole lot by just gasket matching the ports. Most of your improvements would come from the bowl areas.
On my intake ports I don't go any finer then a 80 grit finish. On my exhaust ports and combustion chambers, I polish them right to a mirror like finish.
When porting aluminum heads you need to use some kind of lubricant with the burrs. WD40 works. There is also an actual grinding grease/compound you can get too. I've used and seen many different oil, greases and waxes used. If you don't use something, as you found out, the burrs just get packed with the aluminum shavings.
Thanx to Mrs Jeff for she relived some of the anxiety I had after watching you drill & grind on that head
you was freaking me out Jeff
Looking good Jeff. I use beeswax on the burrs and when I don't have any I use aluminium cutting oil. As some guys said wd40 works too.
Another point about the exhaust ports is that you can actually open up the exhaust manifold a little larger than the ports. This helps prevent backflow and the gases still flow out easily. Great job so far, I love your ambition and confidence to try new things. You're an inspiration. 👍
Countryiron forge. Chalk works well too.
do the same to the intake manifold; kills "reversion"@@mickcoomer9714
Jeff. Firstly love your videos. Keep it up. Secondly, those carbide bits are mainly for steel, but can be used on aluminum. The trick to keeping carbide bit clean is simple. Candle wax. Every do often. Stop porting and spin the bit in a bit of candle wax. Don't run the tool fast. Justca quick touch and go back to work. You will notice the bit will clean up almost instantly after you start working again.
Always loving your work Jeff. Love that you get stuck in and don't hide your mistakes. When you paint your block, the correct paint is in the 'British Standard' database as B.S. 18C39, with HMG ( Her Majesty's Government ) Glidden number GL31557, and Glidden number name 'Dolphin Blue'. Seeing Nissan/Datsun engines of that era in any other shade or colour upsets my OCD.
You may want to look away ;)
Hi jeff. The trick i use, to prevent the burr getting clogged, is from time to time, dip the burr in lithium grease. I hope it helps.
I worked in a engine machine shop throughout highschool. Muriatic acid is what is used( pool cleaner) to eat aluminum out of cylinder bores and other surgaces without damage to steel surface. It works on burs and files after porting.
Don't heat the bur it will mess with the hardened bur.
Don't forget to blend the valve seats with the runners, pretty simple and removes turbulence at that sharp edge. And for cleaning your carbide tip just grind away at a piece of steel and it will come off.
I really don't know where you get the courage to do things like this. Bravo Jeff!
Nice work Jeff, Porting takes time but i've always felt it's rewarding work. I've heard the tool doesn't clog up if you dip it in automatic transmission oil but I've never tried it. As yo said, the walls dont have to be super smooth...
Hi Jeff.
A trick with the burs, use metal polishing wax to keep the burr lubricated and the won't hold the waste steal or get as hot.
Regards Dale
Hi Jeff - try spraying a little WD40/ Inox etc on the burr before grinding and the alloy will brush off easily with a wire brush or similar - just dress it with the wd 40 now and again and it is much easier to keep clean... Spent a good few hours porting Alfa heads like this. Thanks for the great vids !
Nice work! Love the DIY cylinder head porting
Nice video as usual, if you use cutting oil or Wd 40 when drilling alumininium your drills will stay sharper and leave a nicer finish, probably can be used for the die grinder carbide bits too. When milling aluminimium we always use coolant, the milky white cutting oil to keep the bits cool and flush the chips away
Hi Jeff, you may have picked up a burr suitable for cast iron or steel. But like others have said. Keep grinding and use wd 40 (a small container and to dip into) It will eventually clean itself. Also, you did well to use your drill press but mostly we just use a high speed air drill...it offers more flexibity i.e. to tilt over incase the drill wanders off centre. Broken manifold studs we do the same with...never use an electric drill..too heavy and slow rpm. You've had a fair bit of welding done to the head...I gather you had it straightened and pressure tested? Good idea to have it pressure tested after porting. Cheers
I thought I was doing the right thing with the drill press, but you are correct that the bit still wandered more than I would have liked. I may go through then and use the air drill to finish off the water galleries then.
Yes the head was welded and re-straightened. Apparently it had been warped and shaved flat previously as the base was flat but the top was warped. The welder re-straightened the whole thing and then it was machined on 3 sides.
Sorry I missed your reply. I posted before that you might want to consider cam tower shims. I think by memory which are stainless shims (0.9mm) that are installed under the towers...something to do about timing chain tension.
Already got them waiting to go in ;)
Scariest video yet! Glad the first hole you drilled was correct afterall.....nice work as usual
Jeff you can get specialty carbide burrs that are designed for aluminium with a more open cutter and anti-clog flute design. If you buy the generic burrs like the ones your using you will have to either coat them liberally in WD40 every minute or so or use wax to stop the burr clogging.
Nice work Jeff! Two blown headgaskets were some of the worst memories of my 240Z!!! Cheers Tiger.
Hopefully none for me ;)
Great shit man! You put in a lot of hours into this channel and it’s definitely worth! So glad I found this
Thanks mate. I enjoy it, but it is a whole lot of work.
I use engineers marking blue and a scribed. Gives a better line to work to. Basic port matching is such a simple way of improving the breathing of the engine.
D
I work on aircraft and would definitely reccomened aluminium cut burs instead of the steel ones. Wont clog and will work alot faster
I am now learning the difference.
Steel burrs clog when using them on aluminum. In the future if you get a burr for aluminium it will take half the effort and time. But make sure long sleeves and face shield are used and cover your shoes cause the shavings that fly out make some NASTY splinters.
Cast aluminum alloys can be muddy. Best tip for you to keep your burrs clean is WD40 often while working. Don't let it build up at all in the tool. Sandpaper rolls are affectionately known as Tootsie rolls after the candy namesake.Best of luck
Thanks mate, I will try that next time.
Some of the best gains on any head are to be had in and around the valve seats, including the valves themselves. This is by far the most restrictive area. The potential flow here ranges from zero ( valve closed ) to whatever your head can achieve at full valve lift . This will vary from head to head but will always be less than the other areas of the port due to the restrictive nature of the valve guide boss, valve guide and valve stem/ back . Any gains here however minor they may seem will really improve overall flow , especially a low valve lift. This is really useful on any engine particularly a road / street one like you’re building. I’d highly recommend talking to a good local machine shop about cutting three angle valve seats and reducing your valve seat to around 0.070 inches. This is fairly inexpensive . Also good quality valves with waisted stems and a flatter back profile . Or depending on the quality of the oe valve you could modify these to some degree. Bullet nosed valve guides are a good idea too. On the exhaust , it’s about reducing pumping losses so a good radius on the edge of the valve face can aid reverse flow when combined with the other mods . I hope I’m not teaching my granny to suck eggs here ! but these mods are relatively inexpensive and really enhance your engine package . Keep up the good work 🏎🚀
I have gone similar (or further) than that on the 911 engine with 6 angle valve seats, etc. I am just looking at lapping the existing valves in this situation. It is a rabbit hole, that is easy to disappear down, and I am trying to resist. Which is why I only got the machinist to go as far as he has.
Ryan McNeill also don't forget the backside of the seat in the bowl area. I'd argue that's actually the FIRST place to clean up, as it's a huge ridge on factory seats and also gets you the some of the much needed bowl area to make these heads shine.
Good point Jeff , I’ve fallen down that hole myself a few times! Nathan , 100% correct . I’m planning on doing a Rover K Series head soon and will pay particular attention to that.
Never been a fan of lapping with the 'newer' type engines...I didn't have to being a cylinder head machinist. There's a theory that heat expansion on valve seat differs to that of the valve and therefore you don't get a good seal. Are you replacing the guides as well?
No. I am keeping the same valves, guides, etc, so the exact same parts are going back in the same spot. I got the machinist to have a look at them and he was happy with them, so hopefully they don't need much to keep them good.
I used small sanding wheels when I did mine
Great info Mrs Jeff I never knew what BRE was before this! Granted I never looked into it either
Just to add Jeff. You might be up for some cam tower shims pending how much has been machined off the head. An engine that old...could've been apart 2 twice before. Cheers
I already have them ;)
This is tedious work, but definitely gets results, especially matching manifold to head. My wost mistake was guessing when i had the head planed; the engine ran bloody well but i had to beat it with a stick to make it stop, it was dieseling so badly; head off again and some measuring with a burette (like I should have done to start with) found I'd given it a compression ratio of about 13:1!
Mine has only been shaved 0.8mm off the base, and 0.2mm off the top, so hopefully it should not be too crazy, but I will try to check it later.
Just this one time or total shaved off?
yeah thats about 20 thou in old timers language so not too radical, but it does pay to measure the chambers so a) you know your exact cr and b) you can even them up (if you have worked the chambers).
I will measure the chambers as well. I also have shims for the cam towers to keep the chain geometry in check.
racketman2u well with the p90 and flat tops he'd have to shave a TON to get into that realm. ...now, my flat top MN47 that I'm running a turbo on.... That's another story ;-)
Comment for the algorithm 👍I love Z cars...and the 240Z is a work of art.
The the two Peter Brocks are also linked by the Daytona coupe car. The American Peter Brock was the designer of it for Carol Shelby back in the later 60s. The Australian Peter Brock died in a Daytona reproduction he was driving.
I only put that together yesterday when I was researching it. Creepy!
and to make things more confusing there are two head gaskets for the L28, hopefully they got you the right one.
did you get a 3 angel valve job helps heps, on the vw golf the flywheel is easy to lighten 2 kg then balence with crank, then wieght the rods and pistons lighten them as set´s and get them within 2grams then you have what is called blueprinted. getting the rods and pistons done is alot off work but pays off big time in the end
regards
Sören
I am not going that far on this engine, it is just a street engine. Just lapping the valves, a good clean, bearings and gaskets.
the weight off rod and pistons is easy and something you should do it´s just as easy as what you just did,and you have all the tool now he he
oh and look in from the manifold side can you see the hole valve opening/most off it
I will do some research and see what I can do.
Small tip Jeff small tooth cutters can be cleaned up with some scrap steel to grind out the alloy trapped in the teeth 😊
Alloy burs have bigger agressive teeth so they don't clog with alloy.
Your one is for steel 😊
Someone else said the same thing. I will give it a go, as it is still clogged at this stage.
Once you get that burr cleaned up, use WD40 while using it to keep the aluminum (or aluminium) from clogging. WD40 has also helped me clean the burr up after clogging it as well.
You are one lucky man! The car's not bad too!
Awesome work on the porting! The Achilles heal of the Z is the head. All the time and work will pay off. Are you doing new rockers? One thing I had done is have the existing rockers resurfaced.
No the rockers are still in good nick, just getting new lash pads.
Home Built By Jeff right on, I had read awhile back that when changing the cam it is sometimes good to resurface or replace. I’ll have to dig for it. Changing bore size at all?
Nope, reusing the flat top pistons and valves, etc, that I already have. Just giving the engine a nice freshen up.
Home Built By Jeff awesome! Flat tops for the win! Our engines will be similar. I have the p79 head though so I have to do a few extra mods, is yours p90?
P90a
Hey Jeff, i seem to remember that the camshaft towers should never be removed from the head as they are bolted on and then line bored. Therefore impossible to line up if removed. I had to bin a Datsun 1600 head because of this, hopefully the 240 is different? You might like to just triple check this.
I heard you weren't supposed to remove them either, but the machinist took them off. As the head has been shaved, I need to put shims under them anyway which is a common mod. So there must e a way to do it. The engine shop is the go to for Datsun rally engines, so he knows what he is doing. I will ask when I go to put it back together.
Martin Armstrong it's not that big of a deal. You should number them ideally, and before you torque them down fully install the cam and ensure it rotates smoothly. Making sure to rotate the cam as you torque the towers down will keep them centered properly, just take small torque steps. Having them out of order can make it impossible for them to ever line up though.
Yes , number the cam towers to be on the safe side. They also have dowel locators so taking them off and on is ok. Mixing cam towers with other cylinders can be difficult.
I need to check to see if he marked them. I really hope so!
The reason for leaving the intake ports rough is to aid with fuel mixing by causing air turbulence
Go watch the videos @Jafromobile does on head porting, I believe he avoids the buildup on the cutter by using copious amounts of WD-40 to cut with.
I have watched a few, his videos are great. Super detailed.
Where are you are porting inputs and outputs where the black marks were made do you grind the aluminum all the way down perpendicular to the surface
Boy, you made me really nervous there, Jeff! Clearly, you are much MUCH braver than me.
After spending some time at Performance Developments, working on a MUCH more expensive engine, I wasn't as worried working on this. Just taking my time and being careful.
Get yourself a product called Boelube made by Orelube Corp. It is a machinist paste that keeps the flutes of a double cut burr from getting clogged up with aluminum..
I use Castrol Stick Wax !! Slovers Porting Service !!!
I've widened the center bore of plenty of wheels to make them fit something else. WD40 and cutting fluid is your friend in situations like these. Also, think that may be a steel bit =)
Ms. Jeff calendar??
You use candlewax or WD-40 as a lubricant when using sandpaper or any sort of cutting mechanism on aluminium otherwise the aluminium will blind to the tungsten carbide Teeth or the sandpaper grit
As others have said liberal WD40 and it will clean itself as you go. I gave up porting a head, but kudos to you!
I haven't read through all the comments, and I'm only up to 7:30 on the video so far. I also know this video is also 9 months in the past. I found the series a few days ago and I'm catching up.
Two other types of holes you need to pay attention to are the oil supply holes sending oil from the block up to the head (oil pressure for the cam and valve train) and oil return holes from the top of the cylinder head that drain the oil coming out of the cam (L28 cams had internal oiling, L24 cams used an external spray bar bolted to the side of the cam towers).
Identifying the oil supply holes can be done with this diagram:
forums.hybridz.org/topic/115160-l6-cooling-system-diagrams/
You should be able to locate return holes by shining light up through the crank case area and noting the illuminated holes in the block gasket surface that should also correspond to the drain holes from the valve train area.
check with the machine shop, they may have pressed in plugs just below the surface, welded the face and skimmed
I thought about doin this when I rebuilt my supra engine but was scared to so I didn't Lol, good work, I like the longer video.
How about the 2 dowel pin holes? Its been a while since i've had my head off. Did nissan put them on 2 head bolt holes or did they have their own hole?
Around the head bolt holes. The holes are still there and good, I just need to get the dowels.
Please paint the engine when you're done.. I want to have a video on painting the engine by you jeff!
I'm kinda 50/50 if i'm going to paint my V4 engine.
I have the paint standing by ;)
And what was the purpose of closing up the water holes, just to open them up again? I must have missed that.
They were corroded and spreading, so they were welded up to repair the corrosion and redrilled.
Try grinding some brass or use a file brush
Awesome
You should enable the the "sponsor" option on RUclips if you can.
I just had a look, but it is only open to channels with over 100k subs at this stage :(
Home Built By Jeff well shoot that is stupid. I will just keep buying stuff then.
What about Patreon?
I am surprised your machinist left the very small dimples in the head surface. you can see them clearly at 9:23. Keep wrench'n!!!
It was where the holes were re welded. Well away from the combustion chambers, but I did notice them too.
T Hyatt Clearly you have no idea what you are talking about. These head castings have a series of ( dimples ) along the face as machining indicators to gauge the minimum thickness of the head. L series heads when machined down affects the timing chain geometry and the chain tensioner but it’s easy to just blame everything on the machinist hey.
T Hyatt I guess by the term “ keep wrenchin “ you are murican and can’t handle being wrong but hey bud it’s ok. I understand now you only have experience in pushrod V8 heartbeat of god bless Murcia technology. It’s funny but hard sometimes as a pro to watch these amateur hour guys who have never done it before , teach the masses on RUclips. Sorry Jeff but it is clear you struggle with knowledge on these engines and you should just leave this stuff to the experts.
nice work . spray lots of wd40 to stop alloy going everywhere and tool clogging
now don't touch the intake ports any more , the big thing is the exhaust ports
press out the exhaust guides .cut 10mm off and round off end
cut the exhaust guide boss at about 45deg angle and shape to get the air around the guide
cc the head and get comp ratio right . 72 cam = 10 to 1 . 76 cam 11 to 1
spend money on a good long branch tube headers [ bigger is not better ]
look at my you tubes
Not sure if I can be bothered pressing out the guides, but I will look at smoothing out the exhaust ports more. I am not going to be going crazy on this engine. It is just going to be a warm street engine. I have triple OER carbs from Stewart Wilkins so it should be nice, but just not nuts.
OK .just shape down the sides of the guide boss with the guide in
that 90 deg boss is the biggest restriction to air flow
you will have good air flow in and bad flow out .exhaust flow needs to be about 75% of the intake
at WOT you will hear the exhaust reversion out the carbys
i hope this helps
I will have a look and see what I can do. Just getting tools in there (and not damaging anything around it) is my main issue.
Port matching is a 70s gimmick, today we step port to resist reversion. Put a 1-2mm chamfer on the inlets and the same on the exhaust manifold. Better still the exhaust manifold bias higher on the head so the sonic reversion can't smash back into the head.
Use WD40 when machining / drilling aluminum, stops galling. Aluminum melts at 800c.
I was using the wrong type off burr for aluminium, but I found later the easiest way to clean out the build up was to use it on some mild steel.
Jeff: "I'm not going crazy power with this engine"
Me: "Oh no. No Akuma Zetto's engine" :(
When your die grinding bit clogs up with aluminium, just grind some mild steel with it and it will remove itself.
I will try that. I haven't been able to get it cleaned up any other way yet.
Not for the faint hearted but yeah, this is awesome!
Jeff, next time you're doing some drilling like this, use some Rocol Cleancut for better results(reference your comment around 9:20). And also your drill bits will stay sharper for longer! www.itwpf.com.au/rocol/rtd-cleancut/
I’m pleading ignorance..............if the water ports were there when you took the engine apart why do you have to drill them out?
They were badly corroded to the point that they were getting close to the combustion chamber in spots, so they were all welded up again.
Thank you
Woah, drilling the head, scary
Really nice work Jeff, I did similar in the Ford Endura engine I'm rebuilding to my 98' Ford Ka, besides the porting I also cleaned up a little the combustion chamber.
It REALLY took a lot of time, but the satisfaction later pays for it.. :D
The video is not released in my channel yet, but here is a picture of the work done in the chambers:
instagram.com/p/BfGG-goDHCw/
And a picture of how it was originally:
imgur.com/Mw191ig
About the gasket, it might be used in other versions of the engine/head, then it has more holes than you need, for the Endura engine was the same case.
Cheers,
Paulo
Nice work. I probably won't go that crazy on my combustion chambers as they look like the casting is much better than what yours was.
add soap or wax to the burr before porting
Use chalk to coat it so that the aluminium doesn’t stick to it
Have you considered the possibility that you have the wrong gasket for your engine?
Possibly, but I believe it is the correct one.
Home Built By Jeff they made two variants of gasket. Yours looks right for the later p90 head. And for mixed engines using older blocks and newer heads, you generally gasket for the head not the block. That said, I've seen both ways run on street engines... (In other words, don't lose sleep over it)
Thanks mate, good to know.
too late: 280Z valves. Unshroud combustion chamber
Jeff, I really like your work ethic and the knowlege that put across, but could you please cut down on the "err's" and "errms" in your episodes. No other youtuber, that I watch, can surpass you in the amount of them.
I am fine when I have time to stop and think about it, but I usually just talk on the fly, so that is why I can't string a coherent sentence together. It is a struggle to get the work done and talk. If I stopped and made up a script each time I would get nothing done. Catch 22.
you should buy BMW X6
Why?
Eww reverse flow
13mm deck minimum. I know you know now haha.