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1FastCSX289
08-17-2009, 05:43 PM
Ive got a 2.4L naturally aspirated block over at the machinist. I planned on fitting it with SRT-4 pistons. I bought the pistons already and brought everything to the machinist. He honed the block the bare minimum and he says there is a small lip (a couple thousandths deep) where the top ring changes direction and wears the cylinder bore. He says that if I ran things as-is it might result in premature ring wear......but I dont think he realizes the pistons I gave him are not out of that motor......and I didnt think to ask this to him on the phone........(of course hes closed now and im dying to know).

Heres my question.......that wear spot was caused by the old NA pistons. Is the SRT-4 top ring in the same spot as the N/A piston? Logic tells me that they are lower compression and the pistons do not travel as high in the bore. But I dont know if the ring land is closer to the top of the piston in the SRT negating that factor. Does anyone know if my top ring will even come in contact with the old wear spot.

Id REALLY like to avoid buying oversized (forged $$$) pistons. Im poor!

1FastCSX289
08-18-2009, 08:09 AM
No one?

contraption22
08-18-2009, 08:56 AM
I'll see what I can find out for ya.

1FastCSX289
08-18-2009, 03:47 PM
I brought the NA pistons to the machinist and we did some measuring. Just to update the thread....yes, the SRT pistons sit lower in the bore. The top ring on the SRT piston falls short of the NA piston by about the thickness of the top ring. So.....looks like I can keep the little ridge in the block b/c the ring will never touch it.

Thanks for offering to check into though, Mike.

turbovanmanČ
08-18-2009, 04:21 PM
I brought the NA pistons to the machinist and we did some measuring. Just to update the thread....yes, the SRT pistons sit lower in the bore. The top ring on the SRT piston falls short of the NA piston by about the thickness of the top ring. So.....looks like I can keep the little ridge in the block b/c the ring will never touch it.

Thanks for offering to check into though, Mike.

That is some good info, lets us be cheaper, :thumb: