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Discussion Starter #1
hey whats up guys-to put it short, i only could pull a 13.8 @100.7 on friday. funny thing is that i dynoed 335.5 to the wheels on a mustang dyno(about 385 on a dynojet) on that tuesday(4-26)! i pulled some more fuel out on top since that tune, but i dont know why it was so slow? my sixty foots were between 2.0-2.2 on all runs, but the car seems to just fall flat past 4500 rpms. i checked the timing yesterday, and the timing at initial start up is @10 degrees, but rises to like 17 degrees when warmed up! i read someone that had the same problem and thier problem was their tps, but mine checks out perfectly per tsrm. The timing belt is not skipped a tooth, so i just adjusted the timing so that it sits at 10 degrees when warmed up. do you guys think that the timing was too far advanced, causing me to loose power up top? by the way, the cps is set correctly also.
 

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boost freak
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MPH is an indicator of "available" HP. based on your 100 MPH trap speed, you're not making anywhere near 300rwhp. sounds like you've got a boost leak or some other "common" problem...as for the timing issue, sounds like you forgot to jumper the diag block....
 

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Discussion Starter #3 (Edited)
nah i jumpered the block the cel blinks when the terminals are jumped, but what i was saying is that i changed nothing on the car since it dynoed 2 days before, just took out some more fuel up top. no boost leaks that i can tell at either-kinda weird i dunno whats going on. thanks for your input doc
 

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Discussion Starter #5
vac @idle is a solid 20, i didnt do a boost leak test since the run at the track, but i did one before and it had no leaks. i was thinking the same with the timing, which is why i put it to 10 degrees warmed up. i hope that helps it some, i appreciate all the help doc, good to hear from someone experienced like you.
 

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Discussion Starter #6
one more question, isnt the timing supposed to read the same when cold or warm? do you know what would cause it to rise like that?
 

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Do you have a wideband? Is it calibrated? Make sure that you haven't pulled to much fuel and are creating knock and therefore pulling timing like Dr.J says. GL
 

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when this baby hits 88mph
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drjonez said:
if you took out more fuel up top it's entirely possible you're starting to knock and the ECU is yanking timing.....which yields no power....
]


i think this is a good bet. on the dyno my car kept making power up until 12.2 then any leaner than that it fell on its face. you said you pulled some fuel out, what was it before?

+1 for docta jonez ;)

dave
 

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Discussion Starter #10
when they tuned on the street the wideband was reading mid 11s. that was with 14% take out from about 4500. i moved it up to 18% and the ratios were right around 11.9-12.1 when i ran. i think my main problem was the timing though being set at like 17 degrees. i moved it to 10 when fully warm so we will see if that will do the trick. anyone else have their timing gradually move up like that while the car is warming up?
 

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greasemonkey
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i ran a 13.84 at 104mph 2.41 60ft last time i was at the track, 10psi runs, im in fla and it was hot as fook, got sunburnt on my left side sitting in line to run. with the weight of the car, i was getting ~320rwhp calcs. havent been on a dyno to verify though, still ~double at the wheels what the car was stock at the crank. im ok with it.



p.s. 2nd run was end of the day like 5min after the 1st run, no cool down time but i lowered the tire press 5 more psi. helped the 60ft but the engine and i/c were already heat soaked.
 

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Discussion Starter #14
wow good runs i hope i fixed my problems, i will take it back to the track to see what i can run now.
 
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