NEED SOME HELP HERE

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aroracer72 · #11 Post by **aroracer72** » Mon Apr 16, 2007 5:00 pm

This quad was dougs before i bought it and he thought it was a JE but a JE that would be running around 9:1...........but then i showed pics a while ago and found out it wasnt a JE....and most likely a wiseco!

Now i have a stock ASSO piston here and it measured out as you said......and this piston and the new JE are taller with this piston being slightly taller. So this motor was said to have been put together a little before the original group ride at jaybars a few years back.........soo..........???......could i get ahold of another one of these pistons???
Chad

cannondale27 · #12 Post by **cannondale27** » Thu Apr 19, 2007 2:36 am

Even with a stock piston the shortrod Falicons were higher than 9:1 probably around 11:1maybe a little less.Looking at the piston I really think you might not be getting a good measurement.Nobody knew back then that the rods were short.It wasnt caught right away so there was no reason to put a custom piston in there.In all likelyhood it was just a Wiseco 97mm of which there were two designs made a high and low compression.Yours was probably high one.I will go on a limb here and say your JE will probably make 20hrs of real racing hours.So put it in and mid season get it out or fix you Falicon and buy a CP from Timbo.If really interested in a accurate compression ratio this is how you do it.Require very accurate measurements but any machine shop worth anything will be able to do it.

http://www.pontiacstreetperformance.com/psp/CRcalc2.html

aroracer72 · #13 Post by **aroracer72** » Thu Apr 19, 2007 3:10 am

I measured the piston again using a digital micrometer and from the top of the wrist pin whole to the deck of the piston reads .612(approxiamtely) and the JE reads .667 so the JE is taller by a few thousands. My dad measured the pistons the first time and he over looked that the wiseco still have the c clip in it and he had that added into his measurement. So after all that this wiseco is .612. What compression would i be running with this new measurement......this time i know its accurate because i did it myself. This piston and sleeve are still good i could probably get new rings and be completely fine. Or maybe i should just put the JE in and run it for half a season then rebuild it fully.
Chad