Wow! I was amazed to see the TBI head series, then you hit me with the Jag V12 and TPI. So awesome. After you show what you did on VW heads, I'll have to repopulate my wishlist.👍🏻
Great video guys thanks for sharing. I am surprised at the chamber design. I would not imagine that there would be any work being done during overlap because of the exhaust seat installed so low in the chamber. Thanks again for sharing the info have a good day!
Legend has it, those cylinder heads were the last development/design by Walter Hassan when Coventry Climax was absorbed by BMC. Hassan deciding to call time on racing activities after building the championship winning F1 engine for a few seasons. Engine capacity had changed yet again and Repco had a power unit ready to go. It wasn't long after Keith Duckworth had penned the DFV with Ford money. The other personalitys that stitch the entire bunch together are the Costins and of course Harry Westlake. Great people looking at what they made and achieved with very little money. As is the English way of doing things🙂 You will have nothing and be happy🙄 2000 years too late😆🙂
Separation bubbles, the bane of aero. The only way they help you is if the air speeds are high enough. Otherwise they're choking your flow because some of it is going backwards.
Really good video Charlie. I wonder if the DV heads are off a larger displacement motor? Looking at the swirl numbers, I'm thinking that the squish squish action will be critical to mixture motion and mixing. On closed chamber Cleveland's, I used to minimise the piston to head clearance as much as I dared, in order to maximise mixture motion/turbulence. I was trying to get a very violent motion at the end of the compression stroke. It was common for my motors to erode the machining marks off the tops of the pistons in the squish areas.
Yes great video finally some light on great jaguar V 12 cly heads they have Potential with the head mods and A good cam, the dual throttle Bodies are not as good as I thought Stock there 70mm each how About on single 80 mm for better Response with central location On the manifold.
These intake runner manifold needs a computer or vacuum controlled resonance flap to devide in 3 at lower RPM and combine to 6 at higher just like 1991 Opel / Vauxhall Senator 2.5 and 3 litre Dual Ram system.
@@servediocylinderheads If I had the money I would try to adapt the GM Opel Dual ram system x2 on a pre HE V12 bored to 6 litre, that would make decent torque and HP :-) Scrap all post 1983 HE heads and get all pre HE heads and British Leyland brand stamped HE heads you can find, if BL is not stamped on those alloy castings heads valves and seats are indian crap also indian labour and metalurgy. DOES NOT WORK. Never buy a Jag V12 engine not made under BL....when BL went and Jaguar overtook the production independantly metalurgy Quality on the engines went down dramaticaly same story with cranks...The early ones were well balanced, the later ones weren't so well balanced The earliest V12 engines were by far the best!
I am in the UK so our Jag engines my be different spec, but here later ones were marketed as "HE" for high efficiency, I believe they made slightly more power. May be that is the different chamber shape?
The heads on all V12 HE are basically the same. With the exception of PRE HE ( flat heads. Combustion chamber in the piston) and the 6.0. Which has slightly bigger combustion chamber. The whole purpose of the HE head was to meet California’s pending emissions rules. Calling it a HIGH EFFICIENCY head was pure marketing. . May even have credit to its origins. ( 1927 Buick FIREBALL). Buick retained that design until 1954. Then Chevy adapted it and kept it through the early 1960’s on their 6 cylinder.
The best head for the V12 is the early Pre HE head. Swirl is induced by the angle of the intake port . The combustion chamber is in the piston. A full Hemi chamber. With squish provided by the edge of the piston. Proof? The horsepower is the same even though compression is much higher on the HE.
Remember that you are dealing with a 12 cyl. 5.3 = 441 cc per cyl and the 6 liter is 500 cc per cyl. So the port isn’t feeding a significantly larger cyl.
Keep that chamber like it is and run some flat top pistons that almost kiss the head to get squish and you should have a screamer! It may need water injection to prevent detonation but who cares big compression and extremely fast flame front should make an engine that absolutely can scream at rpm.
I’m sorry, you are wrong. The HE limits horsepower ( pistons are already flat top.) The 1971-1980 heads flow much better because the chamber is in the piston. The HE heads force air to make directional changes not needed in the earlier pre HE heads. HE heads was to meet California emissions. Not make more power. High Efficency was purely a marketing effort.
@@servediocylinderheads Biggest problem, all Jaguar heads were cast and assembled in India at Standard Motors from 1983 on, many had badly installed valve seats that fall out if you push the engine hard on Autobahn in Germany or doing motorsport. Here in Germany every second V12 dropped valve seats when the owners went chasing Mercedes and BMWs on Autobahn, Jaguar stopped selling 5.3 liter V12 to Germany, early pre HE had british made heads and later 6.0 had US spec made heads that were uch better. But never use a HE V12 and drive that engine hard!
@@servediocylinderheads maybe the He heads after 1983 suck as hell and are very prone to let go exhaust valve seats. As long British leyland during the 1970s until 1982 made those heads they were fine but something fundamentaly changed in quality after 1983 until 1990...after 1991 Ford manufactured the heads and it was fine again.
Seriously !?? Jaguar V12 PROVED itself as a Piss Poor engine Both in retail AND even carefully fettled ($$$$) Race use. Unreliable and woefully LOW in performance. ALL brochure and after the fact Bleats notwithstanding.
Great video 👍. I like the collaboration with Mark, because it's not just numbers, but a conversation about everything taking place.
It was a good day! Thanks
It is very cool to see alternative old school designs.
I agree. Thanks
Wow! I was amazed to see the TBI head series, then you hit me with the Jag V12 and TPI. So awesome. After you show what you did on VW heads, I'll have to repopulate my wishlist.👍🏻
Funny!
Well designed head to a point but .in other areas not so much .will be interesting to see how this develops
This is some very nice work, that you do here! Heads off Charlie! 😊
Great video guys thanks for sharing. I am surprised at the chamber design. I would not imagine that there would be any work being done during overlap because of the exhaust seat installed so low in the chamber. Thanks again for sharing the info have a good day!
I would think scavenging would be low, one of the reasons D.V. modified it the way he did. Thanks
Man, waking up and no coffee yet, I swear I was watching one of the ole lady’s Adam and Eve advertising videos.
Hahahahaha! There was a comment like that filming this!
Glad to see you breathing new life into old jags 👍
I love different engineering and how to improve it. Thanks
It's probably an optical illusion but the spark plug looks like it has no meat left for the threads to bite. Such an interesting design
Legend has it, those cylinder heads were the last development/design by Walter Hassan when Coventry Climax was absorbed by BMC.
Hassan deciding to call time on racing activities after building the championship winning F1 engine for a few seasons. Engine capacity had changed yet again and Repco had a power unit ready to go. It wasn't long after Keith Duckworth had penned the DFV with Ford money. The other personalitys that stitch the entire bunch together are the Costins and of course Harry Westlake. Great people looking at what they made and achieved with very little money.
As is the English way of doing things🙂
You will have nothing and be happy🙄 2000 years too late😆🙂
That’s a great prototype hopefully it will be in production as a performance parts
I think with some plenum reshaping it could work very well. Thanks
Separation bubbles, the bane of aero. The only way they help you is if the air speeds are high enough. Otherwise they're choking your flow because some of it is going backwards.
Wow, watch the deshrouding of the valves on an HE head by warjohn from down under for his 6.7 liter build. This is informative
Post the link. Thanks
Now I’d like to see some work on pre HE 5.3L heads. And have you seen the manifolds for carbureted version 😮OMG
Never have.
“Doc” did a nice job massaging that chamber, I’m surprised it didn’t help even more. Interesting design, the exhaust looks terrible to me😂
Me too, it works pretty well actually. Thanks
Really good video Charlie. I wonder if the DV heads are off a larger displacement motor? Looking at the swirl numbers, I'm thinking that the squish squish action will be critical to mixture motion and mixing. On closed chamber Cleveland's, I used to minimise the piston to head clearance as much as I dared, in order to maximise mixture motion/turbulence. I was trying to get a very violent motion at the end of the compression stroke. It was common for my motors to erode the machining marks off the tops of the pistons in the squish areas.
I am sure that worked well! Thanks
Would most definetly utilize a good wire feed welder in places to reform .but I'm sure you see stuff that would benefit better than doing that
Thanks
Yes great video finally some light on great jaguar V 12 cly heads they have
Potential with the head mods and
A good cam, the dual throttle
Bodies are not as good as I thought
Stock there 70mm each how
About on single 80 mm for better
Response with central location
On the manifold.
It is a good idea and lots less work. Thanks
These intake runner manifold needs a computer or vacuum controlled resonance flap to devide in 3 at lower RPM and combine to 6 at higher just like 1991 Opel / Vauxhall Senator 2.5 and 3 litre Dual Ram system.
So...build it! Thanks
@@servediocylinderheads If I had the money I would try to adapt the GM Opel Dual ram system x2 on a pre HE V12 bored to 6 litre, that would make decent torque and HP :-) Scrap all post 1983 HE heads and get all pre HE heads and British Leyland brand stamped HE heads you can find, if BL is not stamped on those alloy castings heads valves and seats are indian crap also indian labour and metalurgy. DOES NOT WORK. Never buy a Jag V12 engine not made under BL....when BL went and Jaguar overtook the production independantly metalurgy Quality on the engines went down dramaticaly same story with cranks...The early ones were well balanced, the later ones weren't so well balanced The earliest V12 engines were by far the best!
hi at 1.45 WHAT year is the stock head?
I am in the UK so our Jag engines my be different spec, but here later ones were marketed as "HE" for high efficiency, I believe they made slightly more power. May be that is the different chamber shape?
That is a good question. I feel like they are the same. Thanks
@@servediocylinderheads sorry to not have more information.
The heads on all V12 HE are basically the same. With the exception of PRE HE ( flat heads. Combustion chamber in the piston) and the 6.0. Which has slightly bigger combustion chamber.
The whole purpose of the HE head was to meet California’s pending emissions rules.
Calling it a HIGH EFFICIENCY head was pure marketing. .
May even have credit to its origins. ( 1927 Buick FIREBALL).
Buick retained that design until 1954. Then Chevy adapted it and kept it through the early 1960’s on their 6 cylinder.
I think it is due to the chamber's swirl. Thanks
The best head for the V12 is the early Pre HE head. Swirl is induced by the angle of the intake port . The combustion chamber is in the piston. A full Hemi chamber. With squish provided by the edge of the piston.
Proof? The horsepower is the same even though compression is much higher on the HE.
The 2004 Aluminum Body XJ8
Needs a Coyote Swap
Instead of the under cubed 4.2 V8
400hp would scoot her along better:)
Not my style. Thanks
Remember that you are dealing with a 12 cyl. 5.3 = 441 cc per cyl and the 6 liter is 500 cc per cyl. So the port isn’t feeding a significantly larger cyl.
The bigger engine makes it easier to get to the horsepower goals. Thanks
For the six litre thay change the combustion chamber to a more conventional one
Fyi the V12 is a detuned race engine
I was doing some research on that exact thing. It looks like the D.V. he head with the deeper chamber is a 6.0l head. Thanks
Interesting, now if in you can help him get 170 intake cfm at .500" lift he can get close to 500 out of that puppy! You can do it.😎👍
It will be tough through the stock manifold. Thanks
Port velocity baby. 🤓
@@markniblett4857 I will be working on it! Thanks
Keep that chamber like it is and run some flat top pistons that almost kiss the head to get squish and you should have a screamer! It may need water injection to prevent detonation but who cares big compression and extremely fast flame front should make an engine that absolutely can scream at rpm.
.No doubt. Thanks
I will change the chamber a bit I am sure
I’m sorry, you are wrong. The HE limits horsepower ( pistons are already flat top.)
The 1971-1980 heads flow much better because the chamber is in the piston.
The HE heads force air to make directional changes not needed in the earlier pre HE heads.
HE heads was to meet California emissions. Not make more power.
High Efficency was purely a marketing effort.
@@frenchydampier2209 I only know what I have read. No apology needed.
you cant use V12 Jag HE heads because they drop valve seats!!! Only use pre HE and 6 litre heads.
First I have heard that.
@@servediocylinderheads Biggest problem, all Jaguar heads were cast and assembled in India at Standard Motors from 1983 on, many had badly installed valve seats that fall out if you push the engine hard on Autobahn in Germany or doing motorsport. Here in Germany every second V12 dropped valve seats when the owners went chasing Mercedes and BMWs on Autobahn, Jaguar stopped selling 5.3 liter V12 to Germany, early pre HE had british made heads and later 6.0 had US spec made heads that were uch better. But never use a HE V12 and drive that engine hard!
@@Schlipperschlopper Reads like an overheating issue. Thanks
@@servediocylinderheads maybe the He heads after 1983 suck as hell and are very prone to let go exhaust valve seats. As long British leyland during the 1970s until 1982 made those heads they were fine but something fundamentaly changed in quality after 1983 until 1990...after 1991 Ford manufactured the heads and it was fine again.
@@Schlipperschlopper Then you better know your heads history. Thanks
It looks bad for flame travel, detonation waiting to happen.
Hot spots!
Seriously !??
Jaguar V12 PROVED itself as a Piss Poor engine Both in retail AND even carefully fettled ($$$$) Race use.
Unreliable and woefully LOW in performance. ALL brochure and after the fact Bleats notwithstanding.
This comment shows exactly how much you understand engineering. Thanks
Nechápu proč se omlouváš za špinavé ruce. Sdydíš se za ně? Před kým?
I just can't understand how others do videos with clean hands on cylinder head work!