well i finally got out to the track with the new tranny and convertor....was hoping to hit 12's finally, but it didn't happen. I ran 13.2 all day, very consistant too. My last time at the track (not counting when my tranny took a dump), was a 13.55 @ 106.5 with a 2.45 60'

here were my runs today:

1. 13.258 @ 103.56 1.97 60'

2. 13.275 @ 103.79 1.97 60'

3. 13.222 @ 103.41 1.92 60'

4. 13.227 @ 103.90 1.94 60'

5. 13.224 @ 103.61 1.95 60'

6. 13.1 @ 103.94 1.96 60' ------don't have the slip for this one, someone must have grabbed it by mistake....friend in the stands saw the times though, and i saw the 60' on the track.

7. 13.355 @ 102.51 2.04 60'


I'm not sure why i couldn't get 12's....??? List of current mods: Jet Hot LTs (with smog provisions), Random Tech high-flow cats, Dr. Gas X-pipe, Dynomax bullet mufflers, turndown before axle (true dual system), all 3" piping (mandrel), BMR Adj TA, BMR LCAs, MTI lid, SLP CAI, SLP smooth bellows, msd wires, B&M tranny cooler, Rock-On Transmissions Stage IV 4L60E, Vig 3000 stall, Nitto 555's. (oh and i'm stuck with 2.73 gears and i just turned 123,000 miles)

I had about a 1/4 tank, full weight car...even kept in stereo stuff (amp 20 lbs, box 80 lbs).

Can anyone see why my times were low?

 

Yeah, something doesn't look right there . My best time with 2.73's was the 13.43 in my sig, but that was completely STOCK! Considering the mods you've got (LT's and stall converter particularily) your car should have run much quicker (time) and faster (speed) . It doesn't seem like you were getting bad traction either (1.9x 60' times are decent) so it leads me to believe you're losing some serious power somewhere . I don't know if a race built tranny uses more power to turn? (anybody know about that???) Otherwise maybe something was causing knock retard in the motor and killing its power?? Definitely seems something was going wrong.

 

Density altitude? Or, if you don't have that info, weather conditions and track altitude?

Rich

 

Your 60 ft times "should be" more-than 2 tenths quicker for an F-Body w/ the mods you have. For example: you're running 1.9+ in the 60 and should be closer to 1.7+ range. If you can improve the 60s by 2 tenths, you're in the 12s!

I'm also trying to further improve my 60 ft times. When I hook-up with a 1.70 60 ft time, I run 12.40s. However, when my 60 ft times drop to the 1.80s I'm in the 12.50s to 60s. I currently have the rear LCA relocation brackets, but need to add an adjustable torque arm (Spohn w/ floor pan bracket).

http://www.cardomain.com/ride/2189634

 

Considering it's only a 3000 stall, and he's got 2.73 gears though, 1.9's don't seem far off to me? Figure I got 1.9's with 4.10's and factory stall. Unless he claims to have had traction problems off the line, what looks odd to me are the end of the track results ... poor times and slow speed?

 

yeah, i had pretty good traction off the line...only spun the tires on the very last run (13.3)

I'm not sure the altitude or exact temp, but its Sacramento Raceway, and the temp was pretty good, it was cold but not too cold and almost no wind

The Stage IV tranny doens't take any more power to turn....if anything it helped cuz the shifts are lightning fast and always keep me in the powerband


I do have an SES light that came on a few weeks ago. It is the knock sensor, which i know if it retards the timing too much will hurt performance, but since the light came on, i hadn't felt any difference in the performace. However, after leaving the track, the car does feel slower....it won't throw me back into the seat as hard as before the track....did i break something?

 

You make 64 percent (the majority) of your 1/4 mile ET in the first 660 ft (1/8 mile), that leaves only 36 percent for the second half. So, the focus needs to be on the 60 and 660 times to improve your 1/4 ET. When my car ran 13.60-80s, I had 1.90s, 60 ft times and 8.70s in the 1/8.

1997, Z28, Auto, Best ET 12.44 @ 110.13

http://www.cardomain.com/ride/2189634

 

Actually, with a 3000 stall converter I would expect low 1.8 sixty foot times, although I have no idea what effect those gears would have... Can you post a full slip so we can see the splits?

Also, DA can have a whole lot to do with ET and without a weather station you really cannot judge the weather unless you have a whole lot of experience at the exact track you are at.

 

UPDATE

I have had the following maintence done now:
-new fuel filter
-new oil and filter
-cleaned the k&n filter
-replaced both knock sensors (will have a pic of the bad one up tomorrow)
-replaced AC line that was grinding on front sway bar and caused a leak (unrelated, but one less fluid leak now haha)


Worrying discoveries:
-when they were taking the intake manifold off to get to the knock sensors....they said it was loose....very loose.
-the knock sensor harness and the knock sensors are from a 99 camaro. WTF?
-in the 36k miles before i purchased the car, the motor has been opened up for reasons unknown
-when the tranny was out of the car, the shop fixed two oil leaks....rear main seal, and cam position sensor.......well one of them is apparently leaking again...just at a slower pace. They're gonna have to fix that.


Maintence coming soon:
-new plugs TR55s
-compression test
-leakdown test
-Walbro 255 lph fuel pump
-replace intermittantly malfunctioning torque convertor lockup solenoid in transmission. (malfunction seems to be aggrivated by (but not limited to) aggressive driving

 

i'll see if i can dig up the slips tomorrow.

 

I'm no expert but it seems youre on the right track to getting all the bugs worked out. Youre doing everything I would do in the situation. To bad you cant find out why the engine was opened. If the comp and leak down test go well I wouldnt sweet the reason. Good luck.

 

I still need to find the slips....i think i know where they are....2 more places they could be hiding.

here are the knock sensors....i'll let you guys guess which one was fouled!

 

I would replace the 2.73 gears with some 3.73s, if you really want to improve your ET. You've gone to the time, trouble and expense to do all the other mods, why not complete the package. As long as you stay with the 2.73s, you will never realize the full benefit of the torque converter and possibly cam. Everything needs to match (gears, stall and cam torque range) to realize the full benefit of each individual component and complete the package.

 

I knew that was coming. I have plans for gears (3.42 actually). But no money for it right now. With the times indicating problems...i wanted to get to the bottom of that first before any new mods. Once i get the other things tested/fixed....I'm getting a tune.....may help bring up my pathetic exhaust numbers.

 

Bro....get Yourself Some 3.73 Gears,,,,,mt Drag Radials....and A Computer Tune,,,youre In The 12s.....