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View Full Version : Car together(sort of) new best today...



Rich
10-27-2007, 07:25 PM
I think something strange is going on in my car. First of all, here is a car description…

92 LX 5.0 trickflow H/C/I package
stock mass air, air box, 19# injectors, K&N drop in filter 65mm tb/spacer
FRPP 1 5’8 shorties, off road x-pipe, magnaflow mufflers
1993 AOD, 1 piece input shaft, PI 2800 non-lock up convertor
Unknown shift kit, having to do the 1-d-1 shuffle
4.10 gear
275/50/15 bfg drag radials
Car has a/c removed and no front sway bar, other than that full weight

I went to the track today and the car ran pretty good, best pass was:

60: 1.76
330: 5.131
1/8: 7.983 @ 85.85
¼: 12.571@106.87

The problem it is having is at the end of the ¼ mile run at the upper end of drive the car is cutting out. I think it is hitting the rev limiter. The only problem is I should not be running out of gear at 106.8 mph. With the gear and tire I’m running it should be good to about 117-118 mph. (Using 26.1 tire diameter per BFG’s site or 25.82 using most tire diameter calculators.)

Any clues as to what is going on? I made a total of 4 passes today. The mph was: 106.56, 105.67, 106.70, and 106.87. On all of the 106.xx passes the car cut out going through the traps and on the 105.xx it did not. That is what makes me think it is a rev limiter issue.

Nothing scientific but the car does seem to “stop pulling” on the big end.

I think I am past the limits of the stock MAF and 19lb injectors.

MFIELD
10-27-2007, 10:30 PM
Were you at Kilkare, I thought I seen you but wasnt sure. I was there with my red car.

Maximus
10-27-2007, 10:37 PM
Fuel problem.


How did ya do Mike?

MFIELD
10-27-2007, 10:40 PM
Were creepin up on it. Needs more launch rpm, lat run was best until I missed 4th gear :dummy:

Rich
10-27-2007, 11:22 PM
Were you at Kilkare, I thought I seen you but wasnt sure. I was there with my red car.

I saw your car but I didn't know that was your car. In fact I even told some people, after seeing your car, what a nice looking car it was.

Timido
10-27-2007, 11:32 PM
I would bet a trip to the Dyno and maybe a tune would help. I would do at least 24's and a SCT mass air.

Rich
10-27-2007, 11:42 PM
Timmay...

I already have a lightning 90mm mais air. I've got my eyes open for a set of 30's that way if I go the 347 route, that's one less thing I'll have to buy. Once I get them...off to the dyno for a custom tune.

Rick93coupe
10-27-2007, 11:45 PM
What fuel pump is in the car?

Rich
10-28-2007, 12:17 AM
It's a new 255

Rick93coupe
10-28-2007, 12:32 AM
Have you tried running the fuel pressure up to see if it affects mph?

Rich
10-28-2007, 12:36 AM
No, I am running a stock regulator and with the stg 1 cam I'm only pulling about 13 inches of vacuum. That has sort of raised the fuel pressure in itself. With the vac line on, FP is at 39 and with it off it is at 43-44.

I think the injectors are topped out and the meter might be pegging.

Mista Bone
10-28-2007, 09:18 AM
what rpms are you pulling in each gear?

I'm getting 113.4 @ 6000 rpms on 26", then with convertor 5% slippage you back to 107 mph @ 6000 rpms. 6% slippage and your on the limiter if its at 6000 rpm.

Can you raise your limiter by 200 rpm to see? That would give you another 4 mph and see if car still cuts out.

denial
10-29-2007, 12:00 AM
I had problems with hookin. best time was a 13.17 @ 111 mph with a damn 2.32 60ft lol. Would have liked to run on full bottle with 1200 psi. Curious to see what it would do on a good day.

Mista Bone
10-29-2007, 01:00 AM
Rich or anyone else, what is the stock revlimiter?

6000?

Heck if I ever get a Fox I'd was only looking at 13's with AOD, but damn I might have to set the goal a little higher!

High 12 sec street driven AOD would please me fine!

Qtr milerocket
10-29-2007, 01:17 AM
Rich or anyone else, what is the stock revlimiter?
6000?


It would be 6250 for the stock rev limiter.

Mista Bone
10-29-2007, 04:23 AM
so 118 mph - 10% convertor slippage (should be THAT high!) and your at 106 mph.

How loose is the convertor?

How accurate is the factory revlimiter, hopefully better than the factory tach!

Rich
10-29-2007, 08:58 AM
I'm new to this whole aod/converter thing. Hell, this is the first auto I've ever raced.

I never took into consideration the fact that this converter is a non lock-up and it always slips a little....hmmm?

I have two tachs in the car, stock and a Autometer...neither are accurate. I need to do some work in that area.

I am sold on the AOD, nice converter, shify kit thing. Something about leaving at idle and mashing the gas and running a 12.57 !

Jeff88coupe
10-29-2007, 10:30 AM
Nice combo you have put together rich. Be nice if you could find a lentech or Pa transbrake valve body. I had lentech semi-manual v/b in my old AOD....I could shift it myself or just leave it in D.

Rich
10-29-2007, 03:01 PM
Thanks Jeff, I would love to have a Lentech VB. Although at $700 new it is something I would definitely have to budget for. I have scoured the internet looking for a used one and have had no luck, they seem to be few and far between...keep your eyes open.

I'm almost tempted to try and go for an 11.99 n/a before putting the blower on. A custom tune, bigger injectors/mass air, custom cam...it might do it????

Mista Bone
10-29-2007, 05:09 PM
11.99 on a slushbox, sweet!

How much your car weigh?

Rich
10-29-2007, 05:41 PM
The only thing removed from the car is the a/c, front sway bar and spare tire and Jack. Full interior on 10 holes all the way around. I would guess the car weighs around 3200, I weigh 220#.

Jeff88coupe
10-29-2007, 05:53 PM
Bigger injectors and MAS will definatly help you. I'm surprised that the 55mm stock mas made that much power...that motor is trying to breath threw a straw. I ran a set of 30# inj. and a 76mm c&l on my old 302 motor....then swapped them over to my 347 when I built it. I'll keep an eye out for parts for you Rich.

dedpedal
10-29-2007, 05:54 PM
Rich, I have a set of 30s and cl meter if your interested.

firestang70
10-29-2007, 08:04 PM
Rich you were running great there. Good luck with the 11.99.

Rich
10-29-2007, 08:17 PM
thanks firestang...if my car only looked as good as yours!

Rich
10-29-2007, 08:43 PM
Bigger injectors and MAS will definatly help you. I'm surprised that the 55mm stock mas made that much power...that motor is trying to breath threw a straw. I ran a set of 30# inj. and a 76mm c&l on my old 302 motor....then swapped them over to my 347 when I built it. I'll keep an eye out for parts for you Rich.

Thanks Jeff...