[derf]

Ok, so I'm roughly forming a plan which will eventually involve running 20+lbs of boost through an iron block with forged internals.

The question I have right now is, what is a good set of heads to run on an engine like that? What heads can flow enough to feed the power appetite and hold up to the pressures?

 

[stonebreaker]

You will most likely need to have a custom set of heads built. With that much boost, ultimate strength is probably going to be more important than the last possible CFM of port flow. AFR makes a cylinder head with a 3/4" thick deck and a 76cc combustion chamber designed for forced induction. Lingenfelter might also be a good place to look, since they're doing a lot with big-inch turbo engines these days.

Also, don't forget about adjusting the spring pressures to deal with the boost.

 

[derf]

You will most likely need to have a custom set of heads built. With that much boost, ultimate strength is probably going to be more important than the last possible CFM of port flow. AFR makes a cylinder head with a 3/4" thick deck and a 76cc combustion chamber designed for forced induction. Lingenfelter might also be a good place to look, since they're doing a lot with big-inch turbo engines these days.

Also, don't forget about adjusting the spring pressures to deal with the boost.

Oh, this plan has 2 years to be formed before the first part is bought.

And I'm going to be working with a shop knowledgable on forced induction. I just want to start ballparking the big parts now to get an idea of how much this is really going to cost me. I don't want to start a $10K buildup with $5K in the budget.

 

[EDC]

You will most likely need to have a custom set of heads built. With that much boost, ultimate strength is probably going to be more important than the last possible CFM of port flow. AFR makes a cylinder head with a 3/4" thick deck and a 76cc combustion chamber designed for forced induction. Lingenfelter might also be a good place to look, since they're doing a lot with big-inch turbo engines these days.

Also, don't forget about adjusting the spring pressures to deal with the boost.

For boost and high horsepower, just wait for the AFR 225 heads. I will have some production piece here to play with in about two weeks and can let eveyone know what's up...

As a note, there will be a few changes in the AFR chamber sizes. The 76 cc chambers will not be available with only 62 and 72 being the two choices...

Per Tony Mamo from AFR..

"By the way, while I'm on the subject, it is now "in stone" that the 225's will be offered with either 62 or 72 cc chambers from the factory....additional milling can achieve anything smaller than 62 or a figure between the two, but no chamber volume larger than 72 will be available. Earlier information available had indicated 76 cc's, but we ultimately decided that 62 cc's and 72 cc's would cover more ground in various engine configurations."

I'll see what can be done with some valve changes and maybe some chamber rework but sorry, I won't cut up any production heads unless someone else is paying. That's why we have those pre-production pieces.

Stay tuned...

Ed