86formula

iTrader: (3)

LE2 head/LE1.5 Cam, Custom racing clutch, 3.73s, Hoosier QTPs, PCMforless mail order tune, Racetronix fuel pump/hotwire kit, almost full weight, Convo pro bigs and littles.

Not happy with my results (found out there something wrong with my car) but here they are

1st run (first run ever on slicks with a 6spd)
60' 2.02 (4k launch and it damn near stalled)
1/8th 8.543
MPH 84.86
1/4 13.13
MPH 107.83 (wtf?)


2nd run
60' 1.89 (5k launch and spun because of too much tire pressure)
1/8th 8.30
MPH 84.90
1/4 12.96
MPH 106.44 (i think i short shifted twice)

3rd and final run of the night (rained out)

60' 1.86 (6k launch but it was breaking up above 5k)
1/8 8.31
MPH 85.72
1/4 12.85
MPH 109.09

now alot of people would say thats not bad but i went 12.65 @ 115 on a 2.3 60' on street tires with a stock replacement clutch so that last pass shouldve easily been an 11 second pass. i just need some more seat time and my new opti,Coil, and ICM are on the way. i havent touched the ignition system on the car since i got it so im doing it for peace of mind as well as hoping to fix the problem. its breaking up above 5k RPMs at WOT, i cant really thing of anything else that it would be other then something ignition related . any ideas?

robsquikz28

iTrader: (246)

yep something wrong, idknow about the tune but i would say maybe the setup...are the heads and all parts, intake as well all matched properly...is the rockers set up correct.

and if ur breaking up how about a BAD OPTI.

misfire at all, any codes or ses light

afterburner82

iTrader: (2)

Shake it off, man. No one is going to go John Force on a new setup the first time out. Hell, it takes me at least 2 or 3 passes to remember WTF I am doing! Hang in there and head back after you get things straightened out.

86formula

iTrader: (3)

LE ported the heads/intake and the cam was his grind so im pretty sure its matched properly. positive the rockers are set up correctly

new opti is otw just for peace of mind and no codes or ses light. it does feel like a miss

if it was a new heads/cam setup that would be one thing but its just a new clutch and tires lol i should atleast have close to the same trap speed the 12.65 run was on street tires

86formula

iTrader: (3)

anyone else have any ideas?

afterburner82

iTrader: (2)

Since you changed/upgraded your heads, I would check the plugs and wires. Did a tune up on mine and didn't get the #7 on very well. Eventually vibrated itself lose and I had an awful miss. Couldn't even put it in 6th for fear of vibrating the transmission off the car.

86formula

iTrader: (3)

i would think that it would be at all RPMs though if it was that, why just above 5k?

BLK,97,T/A,M-6

Are the slicks taller than your street tires? Are they heavier?

86formula

iTrader: (3)

1/2 inch taller but much lighter. street tires are on 10 spoke SS rims, Slicks are on Convo pros. 1/2 an inch shouldnt account for 6mph

afterburner82

iTrader: (2)

Good point.

BLK,97,T/A,M-6

I agree, I would pull the plugs, You said it was breaking up past 5k? Our LE cars are just getting started at 5k. I shift @ 64 or 65 with mine.

86formula

iTrader: (3)

Yeah i was shifting mine at 6200, you mean pull the plugs to see if any are fouled?

86formula

iTrader: (3)

checked the fuel filter as well, didnt seem to be any blockages but ill replace it tomorrow anyway

BLK,97,T/A,M-6

Yes. If the plugs are white and frosty, the car is lean. Hence a fuel supply issue. If there is a dark plug then its most likely a spark issue as the fuel is unburned....

robsquikz28

iTrader: (246)

probably ur opti man just acting up

gregrob

iTrader: (8)

I agree. Mine would break up at 4500+ when it was bad and it cost me 4-6 cars on the street.

myltwon

iTrader: (1)

high rpm miss could be a number of thing

-bad plugs
-bad plug wires
-bad opti
-bad coil
-bad icm
-bad ground
-bad opti harness
-bad fuel pump
-bad injector
-etc

this what is costing you your 6mph trap right there, your setup I imagine wants to rev to atleast 6300rpm, if so you're missing out on 1300rpm of powerband.

first thing to do would be check and change the plugs, not hard to do or expensive and will give you an idea of if it's a lean or rich condition. also this will let you know if the lean/rich condition is cylinder specific, side specific, or a general condition that all the cylinders share.

another test which is free and easy, is to pop the hood at night and look for arching. this will let you know if you have a plug wire that is arching which can be a common high rpm miss culprit. when you see flashing this will let you know the general area where the suspect wire lies, after you get some light in there look for a chalky grey substance on the wires to know which one is giving you a problem.

those are the first 2 things I would do if it were my car.

86formula

iTrader: (3)

i have new plugs and wires. The Opti, Coil, and ICM are on the way and i might be ordering new injectors if that doesnt solve the problem. The fuel pump is brand new so i dont think its that.

myltwon

iTrader: (1)

well diagnose before you throw parts at it. did you have the problem before the plugs and wires? if not the problem may lie within the recent parts change such as a cracked plug, burnt wires, etc

86formula

iTrader: (3)

no parts change. it ran like a raped ape one day and then just started breaking up above 5k. i thought it was the clutch slipping because it was in power band (and i needed a new clutch anyway) but its still doing it with the new clutch. it feels like a miss to me or fuel cutting out. fuel filter seemed ok but im getting a new one today because i havent changed that since i had the car either