Need slant heads for OHC project

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I have a junk head you could have free but shipping would be a killer. If someone were running down I80 in Nebraska my place would be an easy little detour (~3 miles each way).
 
KitCarlson said:
If you want ideas for OHC cam 6 consider a straight BMW 6 1968+. It is a slanted engine with overhead cam, aluminum head. Intake is on drivers side, exhaust on passenger side. Good power and great economy 30+ with 1985 2.7L eta. Who knows, with work it might be possible to swap head, or use cam and components.
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I don't think that'll work. The bore spacing on BMW's M20 engine is only 3.6 in, and the block is not as long.
 
A while back a friend had an 84 Celica with a straight 6 that had a bad head. This may be the same 2JZ head that Landons65Dart mentioned earlier. Anyway, I checked out my friends old head old and it looked like a really good candidate for a slant 6 swap. If I remember correctly, the bore was the same AND the cylinder spacing was the same! Obviously, there will be a lot of work getting any unoriginal head onto a slant, but it would be worth it IMHO.
Way back there was a guy who built a brand x 300 ci straight 6 with 351 C heads cut and welded each cylinder to fit the 300. It was now a cross flow with 2.02 intake and 1.6" exhaust valves with a great combustion chamber. Ran in the 10s for 1/4 mi.
Does anyone know if this has been done with a 273, 318 360 or 340 head.
 
IMHO, if you are really serious about this, the best way will be to start with a big hunk of billet aluminum.
 
Interesting, i posted last night but it didnt show up? Anyway, is your cam going under the rockers or are you going to run it inline with the valves bucket lifter style? If so, you are going to
Need to regrind the cam to a much smaller base circle so the lift is sufficiant at the valve. If you run it under the lifters youll be able to use the stock lift with the rocker multiplier. Maybe use rocker arms from a 3.8 minivan that have the hydro adjusters built into the tips and pressure oil the shaft. Show us some design drawings if you care to. Using an old toyota head, physically attach it over a plate to isolate its oil and water circuits, then plumb both externally. I didnt realize anything short of a jag straight 6 head was close spacing wise. Remember the 6 bore spacing is not uniform, there is a variance between the 3-4 spacing that is unique.
 
pishta said:
Interesting, i posted last night but it didnt show up? Anyway, is your cam going under the rockers or are you going to run it inline with the valves bucket lifter style? If so, you are going to
Need to regrind the cam to a much smaller base circle so the lift is sufficiant at the valve. If you run it under the lifters youll be able to use the stock lift with the rocker multiplier. Maybe use rocker arms from a 3.8 minivan that have the hydro adjusters built into the tips and pressure oil the shaft. Show us some design drawings if you care to. Using an old toyota head, physically attach it over a plate to isolate its oil and water circuits, then plumb both externally. I didnt realize anything short of a jag straight 6 head was close spacing wise. Remember the 6 bore spacing is not uniform, there is a variance between the 3-4 spacing that is unique.
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I'm going to locate the cam underneath the rockers, possibly engineer my own 1.6 roller rockers with a different angle. In my opinion, fabricating an existing unoriginal head is too much work when I could redesign a mold and cast my own that will work for the slant of I had the necessary equipment or funds. A cross flow head would be ideal, but engine bay space is the limiting factor. It's possible to have a 24 valve DOHC head without cross flow. Port size, shape, and angle would be drastically changed and the combustion chamber would definitely be fine tuned. I think a 4 valve hemi style head would be the best way to go.
 
RustyRatRod said:
IMHO, if you are really serious about this, the best way will be to start with a big hunk of billet aluminum.
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If I had unlimited resources, yes it would be. However, simply adding to the existing head is the cheapest way for me to go. I don't have access to the necessary tools to completely CNC a head from scratch, but I can fabricate framework for a SOHC setup
 
Adding to the existing head isn't going to make a speck of difference though. You're still going to have an awful flowing head. OHC isn't some magic that will turn the slant into some high-revving fire breathing monster, unless you take the time to properly redesign the entire head. In which case, it is debatable that it will make enough, if any, difference over a pushrod motor to be worth the effort (am I making sense still?). More opinion, rotating assembly/oiling is where I'd look if i were wanting to spin something to the moon.

For example, the Ford OHC V8 was mentioned. It just so happens that I went with a buddy of mine to get his '96(?) 4.6 SOHC Stang dyno-tuned. Highly ported and polished Police interceptor heads (because apparently the stock SOHC heads are corks), Ford racing intake and longtubes, .500 lift with 114* lobe sep, and I believe 300ish* cam. I'm sure I'm forgetting other stuff. Anyways, he made 303hp at the rear wheels on JusTune's dyno. Around 350@ the crank. Oh, and this motor spins to 6300, same as a pushrod motor.

Like Pishta said, care to show us drawings?

If you're serious and want to do this personally, have at it. Oddball projects are neat, even if they are pointless. But please don't get peoples hopes way up only to drop 'em off a cliff lol.
 
Brandon Weaver said:
Adding to the existing head isn't going to make a speck of difference though. You're still going to have an awful flowing head. OHC isn't some magic that will turn the slant into some high-revving fire breathing monster, unless you take the time to properly redesign the entire head. In which case, it is debatable that it will make enough, if any, difference over a pushrod motor to be worth the effort (am I making sense still?). More opinion, rotating assembly/oiling is where I'd look if i were wanting to spin something to the moon.

For example, the Ford OHC V8 was mentioned. It just so happens that I went with a buddy of mine to get his '96(?) 4.6 SOHC Stang dyno-tuned. Highly ported and polished Police interceptor heads (because apparently the stock SOHC heads are corks), Ford racing intake and longtubes, .500 lift with 114* lobe sep, and I believe 300ish* cam. I'm sure I'm forgetting other stuff. Anyways, he made 303hp at the rear wheels on JusTune's dyno. Around 350@ the crank. Oh, and this motor spins to 6300, same as a pushrod motor.

Like Pishta said, care to show us drawings?

If you're serious and want to do this personally, have at it. Oddball projects are neat, even if they are pointless. But please don't get peoples hopes way up only to drop 'em off a cliff lol.
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High exhaust lift would be a huge plus with a turbo. HIGH boost, which I'm aiming for, will make the push rods a huge weak point. The low end is already being taken care of. I'm mainly concerned for the excessive boost. Now, higher RPM is desired for overspin without the motor blowing up. I would provide drawings, but I have yet to even start due to lack of time. Again, as I said, this is mainly a personal accomplishment project to see what I can achieve since no one has built this extreme of a turbo slant. Oddball is the goal, and if I do achieve even a slight difference, it's worth it in my books. Extreme porting, polishing, ceramic coating, and more will be done to the head to handle the exhaust temperatures and create higher exhaust pressure. What everyone is failing to realize, is that with a forced induction application, perfect flowing heads are unnecessary. The air is being forced through, and with smaller ports, I'll have a higher low end torque. Naturally aspirated, an OHC would be useless due to lower pressures. Combustion design is going to be the main factor I look into for the head. Valve size will be increased along with 5 angle valve job. Porting will be done. A head redesign is out of the question. $$$ is limited, but I have the necessary resources to do an OHC setup on my own without spending a fortune on custom machine work.

I'm not making any promises, these are all ideas I'm going to try out to see what I get. All I proposed was to pay for a junk head. I'm probably just going to end up using my own '65 head to prototype at this point and find a '68 head (better combustion design) to build. Im trying to eliminate as many weak points in the valve train as possible. I want to do this for myself because theories are great and all, but no one has solid evidence that an overhead cam won't give any additional improvements (yet). I believe I can achieve what I'm hoping for. Others might not. Until I prove myself wrong, I'm determined to do this.
 
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