2.4E or 2.2E pistons in 2.4 rebuild?
 

My 2.4e is apart. Original pistons are very nice but I told by mechanic to look for 2.2S pistons. He found a set of 2.2E pistons which according to him make for a higher compression than the 2.4E pistons? I have not been able to get any #s on this. can any one shed some light?

Thanks,

Mike

ps. my 2.4E pistons are really sweet, just looking for more compression. Any one interested in a trade for ...2.2S pistons??

:eek:

There's extensive discussion on this, do a search. Short answer: yes, it'll be a nice little performance boost. Be sure to clearance your valves/pistons, especially if you're upgrading to hotter cams.

I ended up going with JE's but I had a set of 2.2E pistons to put in my 2.4E+. The 2.2E's should give you a nice boost as dtw said. (I think about a full point of compression more for ~ 9.0 )

2.2S pistons are hard to come by and give you about a 9.6:1 compression on a 70.4mm crank.

if you're willing to dish out some cash JE's are gorgous, are brand new (no worrying about wear), come with new rings and wrist pins, and can be taliored to your needs. I like the peice of mind that is new pistons. 30 year old parts @ 7100 rpms was making me cringe

We compared 2.2T pistons vs 2.4E pistons. Even these should yield higher comp. The 2.4E has 8.0:1 which is low but yet produced 160 hp. I found a nice set of 2.2E pistons ($350.00 $#%^#), and the guy wants to give me $100.00 for my 2.4Es.

Tim, do you still have your 2.2E pistons, and how much would you sell them for. I would need to know today please.

I am already forking out $1K for JE pistons for my 2.0S engine so I am trying to go with good used pistons in this "spare: motor.

I can live with 9.1 ish : 1 compression in a 2.4E motor.

Any idea if and how this engine will run on a 2.4T MFI set up?

Thanks,

Mike

ps. If any one has pistons to offer please call me at 203-245-1766. 2.2E or 2.2S pistons only please.

Actually - I've been trading in 2.2 and 2.4 pistons at around $300-400 range, so that price you mentioned sounds fine for in-spec parts. You should be able to get almost as much for you 2.4Es.

I'm pretty sure Tim's pistons are gone, but he'll be back at 2pm EST...

As far as the MFI, I'm running 2.4L & 9.8:1CR with radical cams with 2.4T MFI, and have no problems.

Question
If the 2.2 "S" piston is rated at 9.8 to 1 compression ratio on a 66 mm stroke and you put it on a long stroke crank 70.4 how does the compression go down.
I contend that it can't.
If you put a 2.2"S" piston on a long stroke crank your CR will be closer to 10.4 +.
What do you think?

Henry,
You are an MFI man. Can you second how the 2.4T MFI will work on my 2.4E with 2.2E pistons. I will accept a good running motor for now and will look into going with larger throttle bodies and stacks for max. performance later with a recalib. pump.

Mike

Mike,
Sorry I sold my pistons already, for the same price.

Henry,
From my research when I was building my hot rod 2.4, I found that porsche seemed to understate their compression ratios. The 2.2S pistons were supposedly 9.8:1 on the 66mm crank, but I expect that they're less than that (I don't have any data on what it actually is measured out to be), BUT when they're put on a 70.4mm crank and actually measured, it only comes out to be about 9.6:1(both bruce anderson and Wayne have published this oddity) instead of the theoretical 10.4:1 or so. There is a definite difference between the 2.2S pistons and the 10.5:1 pistons I put in my motor (more dome) so my thinking is that they're not really 10.4:1 at all.

I've seen the whole lineup , 2.4T-2.2S, save the 2.4S side by side, I wish I had the tools to actually measure out their dome height. There is a definite difference between each set, even when it comes to how much they weigh.

This is all off the top of my head and I haven't looked at the numbers in at least 6 months so what I'm saying might all be heresy

FWIW: You can calculate the actual compression ratio by using this calculator. You'd have to measure all the required input parameters, but you will get an actual comp. ratio.

http://www.csgnetwork.com/compcalc.html