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Old 08-11-2010, 01:16 AM
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supertib
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Default RE: Engiune suggestion


ORIGINAL: jmaxey51


ORIGINAL: supertib

Sorry bro, I dont agree at all...I have been running Picco's for years and modified hundreds around the globe..... They do not need a shim added to run 30%...if someone's is wearing out that fast, its for other reasons then not enough head shims..... The stock compression on the Picco is low enough to safely run 40%, 30% is no issue.....remember we have been racing these engines for many years in many different conditions, not to mention over the years I have done hundreds of these engines and have them running all over the world.... We run ours at even a higher compression then stock, on 30% race fuel and have no issues with engines wearing out early, in fact they almost always go past 10 gallons without needing anything but a rod....

Either way the JPX is a highly underrated mill, arguably the fastest stock offroad 21 on the market, and of course the modified versions are just absurd ! If your running your stocker with an extra shim your leaving a pile of power on the table, you have no idea how much stronger that engine can be with the proper setup and tune...Tho truthfully you likely don't need any more power anyways so carry on ! I will however never agree that adding extra shims is a good idea tho !
fully agree with you right there! mine screams, nothing has out pulled it yet.

but picco or picco based are freakin tight. you cant even turn those over without the plug in. i know you mod engines and you do great work. but im just saying my expirence. i didnt add a shim to my JPX but i did got 7 gallons of 20% before switching to 30%. it was more snappy with 30% but has more top end power with 20% IMO. i just know i have seen 5 people start with 30% and we did everything the same except 20% and ours is still going after 9 gallons and theirs was in the trash at 4 gallons. we were even harder on it and reved the snot out of it and its still going. took over 2 gallons to break in tho. you are probably right on shimming but mine has lasted that long and we still constantly put it on our buggies and truggies when we have a clutch or anything go wrong. never touch the tune, just pop in and go racing.


Its all in the setup and tune....We dont add shims, we usually remove one...However obviously your able to run it fine with adding a shim...... As for the engines wearing out early its likely some other factor being overlooked.... What may I ask was going wrong with the other ones ? not often I see a JPX in the trash at 4 gallons....heck most of them still have huge pinch at 4 gallons LOL ! out of curiosity what setup do you use on your JPX 21 ? as in clutch/pipe/plug/fuel etc ?

i love these engines ! here is my latest one, heck in this video I remove a shim and show before and after !

http://www.youtube.com/watch?v=569nF90fUSQ