Hi

I'm planning to mod my mini cooper s r56 .. so I want to ask which is better 77m pistons or 78m custom build pistons and what the differences in the output performance later ..

Future Modification on car

1) m7 intercooler
2) craven short shifter kit
3) k04 or garrett turbo
4) ddm air intake kit
5) 3" downpipe
6) ecu remape
7) spring booster
8) shrick cams (what is the best cam for 77m or 78m pistons with roads)
9) m7 oil tank

What do you advice me to do more on the car so it will be +350hp??

How much hp the gearbox will handle .. and how to increase the capacity it can handle when the car goes more than +350hp ?

 

Do you have an N14 or N18

 

I have N14

 

oh boy a 2 post fishing lure...

 

Assuming the stroke remains the same going from 77mm to 78mm pistons only adds 2.6% to capacity. This is not much, and in itself does not do a huge amount for power.

There are other reasons that may be advantageous, eg reboring the block gives a clean surface to the bore which has not been scoured by the old pistons.

 

For maximum HP, you'll need the 78mm or more. Robbo mcs has the right idea --- inspect the cylinder walls first, then decide.

Quick response --- avoid the Garrett! And so far, my OEM drive train has handled short bursts of 280 - 300WHP as a "daily driver." Before you do anything, find a tuner that you can work with.

350 HP is an ambitious target --- more like a wet dream! There are very few that have achieved this, and I doubt if any are driven on the street. You need to decide what you want to do with this re-build, then search the forums for build threads that match your desires. I'll start you off with my "journal" --- https://www.northamericanmotoring.co...a-stuff-2.html scroll to my last entry for the most current version. It'll get updated again in a month or so.

There are others with pics that have lotsa good info. Most are still "a work in process" 'cause we're seldom satisfied with the results --- it's an addiction.