Ok, I've gone through the process of elimination.

Since I ran my 9.0 previously on street tires the things I have changed since then up until the night I ran 8.90 are- Installed Daaco converter and topped off tranny with Maxxlife ATF, new tranny input shaft seal, put on a set of BFG drag radials, cleaned my MAF sensor.........

The drags won't hurt me, cleaning the MAF won't hurt me, Maxxlife fluid and a new seal won't hurt me. I guess it has to be the converter.

I really don't want to go above a 2400 stall. Can you give me some details on a midwest stall?? Darkhorse you said it was a "3000 2.5 str", what is 2.5 str??

I know that the cheaper converter are stock shells, like 11" converters just reworked, and I know some of the more expensive ones are 9.5".

Like I said, I'm leaning towards the B&M converters because I can get one that's a 2400 stall, and for about $350, but I wouldn't mind spending a little extra if I can get a lot more performance.

John

 

Hey, good to see ya. That launch you saw in the video is about all the car had unfortunately. It just feels down on power off the line. It's making some power up top I think to be able to pull a 13.5 out of such a poor launch. I was also able to cut 2.1x on street tires before the converter and drags. That was even with my headers and off road pipe so I lost some low end.

BTW where did you run that?? At the hill??

John

 

Thanks Dave, I weigh about 185, I guess that's a little above average. The car is surprisingly light though. I put it on the scales one time, and with no weight reduction it came in at 3380. I'm not sure if the scales were calibrated or not, but after I drove off the scale my buddy drove his stripper model 02 Z/28 six speed on it and weighed 3320.

I'm not racing in a mountanous area, but I'm not at sea level either. The problem is that I'm trapping 4mph higher than some buddies and only running .2 faster, this and I have absolutely no tire spin.

I'm running 255/50/16 BFG drags. They are a little taller than stock, but not by too much.

John

 

185 is what I would consider normal.

I guess then that the only other thing I could suggest is that if you have a cutout in your exhaust then make sure it's closed. You could be losing launching torque there.

Other than that, I would agree with the general consensus that the torque converter may be the culprit. A good racing converter will improve your launch substantially due to the superior torque multiplying effect. That is usually what you're paying for for the more expensive brands is the extra design and development that went into it. Maybe that Daaco converter just doesn't give you the torque enhancement of the other brands?

Good luck in figureing it out....

-Dave C. '97 Z28

 

Did you go to Union Hill???
I ran up there last year and for some reason I was only running 9.2's cutting 2.2 60's...thats before the LT's, ORY, and cam...that track seems really slow to me...but thats just my opinion...and it usually isn't prepped to good on TnT...
It might just be the track, you never know...I haven't been up there in about year...

 

i don't think you will be pleased going from a 2200 to a 2400. go to a 3200 vig and you will see a diiference (it flashes closer to 3800) why don't you want to use a bigger stall?

 

I also think the track is slow. However I was only running .2 faster than a pretty much stock 93Z(less K&N intake) The track prep is so bad I swore I'd never go back unless I had drag radials, I finally got some, so I went back.

I don't want that big of a stall because I rode in a 98 Z/28 with a 3500 stall, and the tach just wandered around. It felt like a slug until you got on it. I'm not gonna do anything too extreme with the car anyway. I'm hoping the jump from a POS 2200 stall converter to a good 2400 stall will be a nice kick in the pants. I might even go 2600, but that's about my limit.

John

 

Dude if you went to the hill, THAT is your problem. That is the slickest track!!! You may not even feel yourself spinning sometimes!!

I was hoping it had gotten better since april but I guess not

Anyways, you still may have a problem with your tranny maybe?? But please dont use the hills time to compare too hehe

Jason

 

And stay away from US 43 Dragway down in Ethridge!!!!
OMG, they mine as well keep the track open when its raining, it couldn't be any worse than what is when it isn't raining...Son of a @#!!!
its sad we have to drive a hour and half to get a descent track to race at...yeah what Jason said, don't use your slips from the Hill to compare to...

 

haha, I know what you mean. I with I could just say "the hill sucks" and call it a day. Honestly, the hill does suck, but the fact remains that with the addition of drag radials and converter I gained a whole .1 Plus when I ran at the hill the weather was almost perfect!! Mid 60s, I'm not sure what the humidity was, but it didn't feel too bad. The car just lacks the power to launch, and I think the converter may have something to do with it

John

 

Dude you should seriously consider a higher stall. Like 3200or 3000 and flash it. I have a 3200 Vig and it hits like a ton of bricks. I am cutting 1.62 60' and with my other mods I am running a blistering 7.09 in the 1/8th.

 

Damn dude, that's moving!!! I just saw a 2400 B&M stall for $239 in summit. Lockup and everything, it will work on my car.

Can I get a deal that good on a higher stall anywhere?? If so tell me where and I'll look in to it. I'm about broke at this point.

John

 

Try calling them and seeing if they can't stall it a little higher. If you don't have much money I hear Midwest isn't bad either. But you really need around 3000 stall to get in your power range. Even if you buy a 3000 stall, it doesn't stall that high normally because you want to let the verter flash

 

Cool, I'll try that

 

FASTZ,
The problem is definitely in your converter. The Dacco converter that you have is actually less stall than your factory converter! On the '93-'97 Z28, the factory converter utilized a 14 blade Corvette style stator. The flash stall is around 2200-2300 rpm. The STR is Stall Torque Ratio...which is to say the torque multiplication of the converter. When a converter is stalled up it multiplies the engine's torque. That torque multiplication factor can be anywhere from 1.4 to 2.8 or even higher for dual stator applications (4L80E). You really need to step up to the 9.5" converter that is so popular. If the 3500 stall is too agressive for you, you may consider a 2800-3000 stall speed. You can get a great deal on a 3000 stall TCI converter through Jegs for $437. It's Jegs part number 890-243105. It's very streetable and should get you some low 1.7 to high 1.6 sixty foots on the drag radials. I've got one in my stepson's '94 Formula as well as in my '85 Cutlass.

If you're really hardpressed for money, you can use a factory 12"
converter from a 4.3V6 S10 truck. You can buy them new from GM (or Dacco) fairly cheap...however, not all of them are furnaced brazed, they don't have heavy duty bearings or super strong clutch linings. It'll probably be fine on motor...just don't use it with N2O.

Kevin