Just got back from the track, Need help!

[kevinw]

I just returned from the track tonight and i'm really disappointed with the results.Have went 7.24 before in the 1/8th and returned with 50#'s,v-2 front mount ,10" non-lock converter tonight hoping for 7.0's, or high 6's.WRONG!I tuned the boost on the street before i loaded it up,25# boost ,780-790 milv. no knock on 110 sunoco.I uncapped the exhaust when i got to the track made my first pass 7.42 at 95mph milv. set at 710 ? no knock my 60 ft. times were off 3 tenths due to spinning and probably due for a new set of slicks. Anyway the car seemed to have a kinda of surge or miss to it at half track but no knock.I bumped the fuel up a pound and a half car ran 7.39, milv. 769, 1.84 60ft. I am running around 43-44# fuel pressure and new walbro 340 pump. I switched chips and unplugged the computer for a few minutes.This chip (testa) has more timing and the car seemed to miss even more at half track.I made one last pass with full exhaust ,boost was at 22# milv. 770, at half track so i turned the knob on my boost controller a fuzz and when it hit 25# the knock retard went from 0-19* and sever sputter .When this happened i lifted but car sounded funny like it had blown a intercooler hose off.Did not find anything wrong all fluid levels are normal as all pressures and temp. What is causing this sputter on top end?Also ,when i left the line on the last pass,my dad said the announcer in the tower said some sort of fulid was coming out under the right side of the car,I found nothing leaking

 

[JToups386]

Based on what you've said, I'd lean towards a bad coil-pack or ignition module. This is only a guess, per the characteristics you've described. I'd like to hear others chime in too!

 

[JUSTAV6]

My car did the same, It was a coil pack,, And it did it later on after I put a set of plug wires on, Got a set on New Plug wires and That did it,,
HTH,
Good luck,
Seneca Lafler,

 

[Chuck Leeper]

???

Uncapping the exhaust could have leaned the motor enuf to get knok and thus the timing was pulled back, resulting in the surge.
Looking at the O2 readings, it's obviously lean. .[780/.790 to .710??]
Secondly, I would look hard at using a hi timing chip w/ high boost,[25psi??] and gas rated at only 110 octane...
it worked at 22 and knoked at 25 when you tweaked the controller...

As for the fluid out of the car.. the noise you heard was most likely the head being raised off the deck and the coolant spraying out..

What are you using for a scanning tool?? If it's ALDL based, it may be too slow on refresh rate to catch the knok B4 the ECM pulls the timing..

 

[qwikv6]

I agree with Chuck. Opening up the dump cap will lean out the motor. I have experienced this as well.

Also, high boost and lots of timing don't mix. You can run very high boost on a low timing chip OR lower boost on a high timing chip.


Good Luck

 

[kevinw]

I have checked for leaks and all i can find is passenger side valve cover, this may explain the drops on the starting line.There is no water leaking the fluid level is dead on where it was before I left no water in oil so maybe i haven't hurt anything, it does have a fresh coil pack and msd wires.Put street chip in this morning boost on 20# with left over race gas and 93 mix pulls hard ,no knock , no miss no sputtering.I did flip through scan master and found code 44,what is this? Someone told me this morning that wher i purchased the race gas , it had been setting a while and ther tanks are in the ground.it could it be bad gas as well? I have ran this setup before with the exception of the v-2,50#s,and converter with no problems.

 

[matt87]

sounds like not enouh octane to run high timing and high boost. you shoulda tried lowering the boost to 22-23 pounds and see what it did.

 

[1badTTA]

Code 44 is EGR malfunction.

I get that code but cant seem to figure out why.

 

[Chris Taylor]

That is what you get for not taking your tuner to the track.