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View Full Version : sr20ve or sr16ve pistons in sr20de ,Compression?



Five10PacksDE
02-24-2005, 03:09 AM
I was wondering the compression ratio's of the sr20ve vs the sr16ve? What I am getting at is, I was looking for a piston in my sr20de to raise my compression to 11.0:1+ other than the 300zx NA pistons. Is the combustion chambers on these engines different? Anyone tried this? I do not want to go through the process of making 300zx pistons to work with sr rods.

_omg
02-24-2005, 07:15 AM
The SR16 and 20VE heads run a smaller combustion chamber, ~35cc vs ~46cc in the other de's. According to the tomei manual the SR16VE pistons have a 6.8cc dish to achieve a 11:1 comp ratio. I believe the SR20VE's are the same however the only VE piston's I've physically seen are the VET's. The N1 SR16VE pistons do run dome with valve relief and are good for ~11.7:1 in the larger combustion chamber. The other option for ~11:1 is simply to run the S14/15 pistons and a thin (around 0.6mm) head gasket.

Five10PacksDE
02-24-2005, 10:20 PM
so you are saying the s14 and s15 NA pistons create a 11:1? I thought the sr20de NA with vtc has a 10:1 compression.

_omg
02-25-2005, 05:47 AM
With the skim and the 0.6mm head gasket yeah, you will come in around the 11:1 mark.

Five10PacksDE
02-25-2005, 12:53 PM
What kind of cams would be good for a sr20de with a 11:1 compression ratio? Is there a ballpark hp range i should hit with these mods? 170 crank hp?

_omg
02-25-2005, 10:11 PM
Are we talking S13 or S14/S15 engine here? Unless you're getting quite serious I'd strongly urge you to go for the 14/15 as it really doesn't take much at all to get 200hp out of them (we're talking unopened engine here)

For the cams for something like that I'd tend towards the tomei procams, 270 each side with 12.5 lift. These will need springs which can cause issues with the VTC. Combine this with with a 70mm tb, use a bigger maf (we use RB25's on DE's) and we relocate the battery and move the intake over, decent headers and a 70-75mm exhaust and give it a decent tune (we use FC's). With the compression this should be good for ~220hp @ ~7500rpm. If you want to go beyond this thats when you start looking at building up an S13 engine or doing the VE head swap.