Say I had a 3.0 crank and I found some forged pistons and rods for a 2.7 that fit my application and I made it 4 bolt mains like I have heard you can. What might be optimal compression ratio to run about 10-15psi on a supercharger and 93. Also what power do you think that would achieve? Would there be 2.7 pistons that would be close to a 3.0? or would it be closer to a 2.9 w/ 2.7 pistons that will actually fit a 2.8 w/ 3.0 crank? I would also need a 3.0 clutch and flywheel right?

 

82.5mm pistons would give you 2976 liter with the 92.8 mm 3 liter crank. Basiclly that is the bore for the stock 3 liter engine. The S4 runs 81mm 9.3:1 pistons and 86.4 mm stroke.


The 2.7 crank and 3.0 crank have the same bolt patter, so you can use the S4 flywheel with a 3.0/2.0 clutch. Just not sure if it will fit but that will depend on what transmission you plan on using.

 

Def the guy I need to talk to if I ever decided to do a project like this! lol. I wish I had the budget for this crap...

 

If you know a good welder, i would just have them make either a good single turbo setup or use a pair of gt28r's. Even with low psi, it would make a better amount of power than tearing into the motor for a small gain.

 

Well, mike, those gains would be significant then?

 

has anyone ever done that ?? i've pondered this myself but couldnt find anything on it ...what would all need to be done

 

its easy, you take your A4 to a lot and trade it in and pay the diff for an S4

 

agree with cincy, o please let us not get into that topic again. any words on my past post cincy?

 

if i could have afford an s4 i would...it sucks by the time i pay mine off and can afford a newer audi all the newer ones are n/a so ill be in the same boat wishing i had boost ....maybe ill go rs6 in like 5 yrs when i can afford one :P
v10 twin turbo

 

You mean this one?

If so, i wouldnt expect any more gains than what a 3.0 puts out unless compression is higher. I dont think the gains would be worth the cost needed to do the engine.