Cams for 3.4 ITB EFI engine
 

Gents,

I have a 3.2 engine upgraded with 3.4 Mahle P&C and Dougherty SS cams.
compression is 10,3:1 for single plug ignition and it has most of the goodies inside to make it go fast for a long time :D
The engine is really nice, delivers around 270hp and has nice torque.

It is really nice but... I want more kick in the butt and wish to take the ITB EFI route, probably with a Clewett package. I have the feeling that the shape of Mahle pistons may not be compatible with high lift cams.
Could someone advice if I can use cams with a higher profile than what I have now and if so what would be the best choice?
Despite 5 to 8 trackdays a year, it is not a track car and I also need excellent drivebility when driving in the city. Superthanks for your help.

Hi,

Those pistons do limit your cam options and even then, you may need to have them machined a bit for clearance, depending on what you use.

A Mod-S cam works very nicely with your package, provided you install some kind of ITB system; carburetors or EFI. The pistons must be machined a little bit to work.

Thanks Steve, is there a type of piston or a specific shape I need to copy for the machining?

My pleasure! If you use the Mod-S cams, you'll need to measure the piston-to-intake valve clearance in YOUR engine to know much material to remove.

The only other path here is to install a set of double valve relief pistons like the RSR ones.

I have the SS cams in my 3.2, but I'm not happy with them.

Is there enough meat in the stock euro 3.2 pistons to do the same so you can use the mod-s cams?
I guess you would lose some compression, do you know if its a significant amount?

Not really,...:( You'll need the same type pistons as I wrote above.

I thought so...