Ok, I know this isn't a forced induction question, but this seemed like the closest forum to put this question in.

What I want to do is put the 40v heads on my 32v. My car is a 97 A8 4.2q. I plan to purchase the 40v heads. I'm gonna doubt that anyone here has tackled this, but I figured I would ask anyway. I'm fairly certian the block/head gasket shapeis basically the same. Anyone know if the pattern will match up?

My goal for the car is 500hp, I plan build a mild turbo setup in addition to the heads in order to meet this goal. Shouldn't be too terribly difficult. I am thinking twin GT28r on roughly 6-7psi will get me in the neighborhood of where I want to be.

Before everyone flames me, Yes I know it's big and heavy, but I like to be different. ...and I figure with 500hp on tap it should be pretty damn fun, but still totally streetable.

Thanks in advance for comments/suggestions/ideas.

Dan

 

If you mean putting on two heads from a 20 valve, they wont match up is my understanding, the porting is different.

 

Lets see, the 4.2 with four valves per cylinder uses timing belts at the front of the engine. The later 5 valves per cylinder V-8's have timing chains at the back of the engine between the block and the clutch housing. Good luck with this conversion. I think you may be urinating into a headwind.

 

Thank you for the information... Didn't know that the newer style engine was a chain style. Good to know though. I think I will have to pursue making the stock engine stronger.