pistons... f7P/R

[maciek]

hi all
next question from "what if" series...

what if I wanted to fit lets say F7R williams or 2.1 litre prima pistons to normal 1.8 16v?
do they differ in height - meaning i must use longer stroke to get compression?
or can I fit (esp. 2.1litre ones) w/out enlenghtening the stroke?

 

[maciek]

no one knows?

do they differ in height? will i lose compression?

 

[Colin_S]

Suposeably if you put 2.1 pistons in the 1.8 the block is too thin and can cause you problems. Also you need a 2.0 crank to do it and the 2.0 crank does not fit in the 1.8 block. When you buy the 2.1 pistons you get the robs with it. If you have a 2.0 block all you need to do is over bore to allow the 2.1 pistons to fit.

 

[maciek]

so this means that F7R or 2,1 (forget about thickness of block) pistons wont do it in bored but otherwise standard (size,stroke-wise) F7P bottom end. This means they are lower - yes? Renault can;t give me any answer...

 

[Colin_S]

You can do it but it means the wall on the block being very thin and the crank case needs to be modified to fit the 2.0 crank.



If you want over sized pistons try http://www.pistons.co.uk/http://www.pistons.co.uk/ far cheaper than Prima, oh and far better service.

 

[maciek]

I want to have more displacement... as there is no... BUT:
i want short 1.8l stroke
i dont want long 2.0 litre stroke. - but this is as i see from what you write here impposible

- pistons.co.uk can make pistons to measure? nice... inquiry sent. what price should i expect?

 

[Colin_S]

If you go for 2.0 or 2.1 pistons then you need different rods and a different crank so lose that short 1.8 stroke.

No idea on price, but it must be cheaper then Prima. I was looking at doing all this before i got my Maxi kit but never did it as i went ahead with the Maxi. I only found that company aftre my car had been started so never priced anything. Looks good tho doesnt it.

 

[maciek]

hmmm... cant wait to get the answer. as i really would prefer to keep short stroke...

 

[BUTRE]

I dont know about this, but a friend told me that the willy pistons are already forged.

I belive him since this came from a trusted

 

[jimbo1]

the 2litre and 1.8 litre con rods r exactly the same size, only the crankshaft is different, as well as shorter pisotns. renault do not make oversize pistons available for the f7 series, so the only alternative our expensive forged items.

jimbo