wow what a big change with the la2 and the 35's... car runs great... it still sounds like its pinging... those flat top pistons are killing me... but nothing some good gas wont fix... would a fmic help with this pinging?
1. You have flat top pistons vise the dished turbo ones? They are probably not forged then, and the compression ration might be too much now.
2. The LA series computers are more likely to knock down the timing on the 84 style intake because the knock sensor input is more "amplified" within the LA EEC.
3. If you are getting pinging, then make sure you have the timing set at 10* BTDC and not way advanced. Pinging is detonation. Detonation means burnt components and/or a blown head gasket.
As for the FMIC, yes, it will bring charge temps down and help, but the car should not be detonating without it. What grade of petrol are you running?
like he said detonation is when the gas explodes before the sparkplug fires because the air is so hot but it shouldnt do it with out the FMIC kit but i would buy one any ways it will cool the air from around 200 degress to around 100-120 degrees.
ok long story short... i did a headgasket and found out the car has speed pro flat top forged pistons in it... the sticker with the timing marks are gone on my car... there is a notch on it and from what i was told that would be TDC? is this correct? and every mark after that is 2*? so i go 5 marks up and that would be 10*? if i back it up to like 8* or 6* when im in boost it pops... ive been running 91 octane.. which is the best up here... but last night i went to vp racing and got a full tank of 100...
they had a pat number on them...Speed Pro ZL2455F75MM - Speed-Pro Power Forged Pistons i check timing yes woth spout out... when im in like 3rd gear around 2300 rpm and i floor it it pops out the exhaust once or twice... then pulls hard... the pining has gone away today with the 100 octane in it... i have timing at 12* and fuel at 40 psi... boost is around 17 psi... it seems fine now but anything besides this 100 octane makes it suck... everybody told me so far to junk the flat tops for stock... but the block has be bored over... what pistons do i need? and thank u very much for this help guys!!!
i've got a bored block i put wiesco's in it that i had ceramic coated in case it goes lean or i want to spray it. If your gona run that fuel and ad more boost you'll want a quality dished piston in it and like navy said the dish will help lower your compression. and be carefull the poping could mean its runnin a little lean.
yes the fuel goes up with boost... yes stock pumps... i think its got enough fuel in it cuz wouldnt it pop even with the 100 octane? ill change the pistons when i have it down for the winter... or just when it blows up...lol
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, builds, modifications, reviews, engine swaps, classifieds, troubleshooting, maintenance, and more!