Combo Failure?

Joined
Jul 26, 2005
Just thought Id post my official 1/4 mile best pass here to see what you guys think. This pass was done on 235/60/15 M/T E/T Streets on stock 86 T-type wheels. Here goes!

2.01 60FT
5.30 330FT
89MPH 1/8th
8.02 E/T 1/th
12.22@114

Car Weight: 3630 with me in it (I weighed about 122lbs then)
A/F ratios were between 11.9-12.1
0 Knock
Launch boost: 0ish PSI
Max Boost: 19psi
Fuel: 93 oct with 2 gals of 100 unleaded
Timing: 19*1st and 2nd gear then 16.7 in 3rd and 16.0 in 4th

Ive seen a lot less combos than mine running way faster E/Ts and MPH close to mine... So Im thinkin a combo between not being able to launch it, not enough converter/boost and launch boost. What do you guys think? -Ben
 
Your timing with that octane of fuel and amount of boost is way too low in 3rd & 4th. You have an effective octane mix of around 94-95. With that much octane I would be running 19psi of boost in all gears and 20* timing in all gears but that's just me. I would also be watching for knock retard very closely at the top of 3rd gear. Also, I would recommend running it in Drive only, not in OD. With your timing and boost, your mph looks about right.

If you were to launch with 6-8psi and hook it, your 60fts would dramatically drop, putting you solidly into the 11's.
16* timing in 3rd is killing your top end mph.

If you had straight 100 octane in the tank, you could turn up the boost to 20-22psi and timing on 20-21* in all gears and really make some good mph. But until you start launching on decent boost, your ET will continue to suffer no matter what you do. The only time this is not true, is if you're making 800 rwhp and you have to baby the car to half track before going WOT.

Your goal should be hooking those ET Streets hard enough to get into the 1.7 - 1.6 60ft range.
With your gas mix and boost, I would have the timing at 19* in all gears as a bare minimum. That is, if everything is up to snuff with the car and the fuel system.
HTH

Patrick
 
Yeah, I was told that I could adjust the timing with the extender chip by running a wire from the gray cable behind the consol over to the appropriate pin in the ecm. I tired that, but I can only change 4 of the 8 cells that I was told I was able to adjust - one of them being the timing adjustment. From what Ive read, Full throttle chips are burned to pull timing like that to prevent knock in 3rd and 4th gear. As you said though, this kills timing and shaves off power that is needed to keep pulling on the guy in the other lane. I know its not a horrible combo, I just know that Ive seen a lot of people goin a lot faster for a lot less with a lot less on their car (and Im stareing at my car thinking 'what did I F^&$ up?!') :mad: Just been trying to crack into the 11s for a little over 7 years now... I guess there's always next year and more parts huh?
 
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