1989 Iroc Z 5.7l
2.77 gears
2800 converter
K&N filters
Magnaflow muffler

So I bracket raced tonight and got a new personal best:

Old:
14.87@92.91 mph on a 2.201 60'

New:
14.70@92.33 mph on a 2.12 60'

The major change was a 2800 Summit racing torque converter. I am running on 16" radial tires and am starting to have problems spinning. Since it was bracket racing I only got 3 test and tunes, 2 of which I spun on. I really think with good traction it would have easily run 14.5-14.6

So my question now is, what mod is next for most bang for the buck? This torque converter dropped me from consistent 14.9's to 14.7's.

My thoughts are underdrive pulleys, 1.6 roller rockers or headers & y pipe. Which would be best, I would like to see my MPH start going up .

 

My only pass with a stock l98 was 13.87 at 101 mph, T5 5 speed, 4.10 gears, Mickey Thompson 26x11.5x16 ET streets, 1.87 60 foot. This was with a carbed performer RPM air gap, Holley 750 vac sec, full length hooket super comp headers, and was a blast for a little 150k mile 5.7. Then the rear broke, then the Trans because of nitrous, then the engine started to get a knock. Was fun though. 13.87 all motor with high mileage was not bad.

 

LCARB'S if you don't have them. I would work on traction before more power. That's the problem I have and it's annoying. I've run a best of 13.3 @ 110 when I should be in the 11's. All the car does is spin.

 

Get it hooked up and you'll find the ET your after. Control arms, relocation brackets, and an adjustable torque arm should do the trick. Maybe some better tires too. Not sure what your running now.

As for what mods after that, EXHAUST, getting it breathing out better and you will see a good bit of improvement. Also you might want to consider a gear swap, 3:23s or 3:42s would be best. Does your tranny have anything done to it like a shift kit?

And there are free mods as well, i.e. gutted air box, throtle body bypass, removing front swaybar. These can all add up as well. Theres no reason you can't get there with minimal effort, just need to maximize what you have first and go from there.

Good luck and keep us updated.

 

Thanks for the advice guys

 

So I just pulled the trigger on a set of shorty headers and a y pipe, would I be crazy to do a Weiand Stealth Ram after that?

 

I agree with the same stuff mentioned above. Keep working on the 60ft times. Box the lower control arms either on your own or buy some, and sub frame connectors. Rule of thumb is what ever time you take off your 60ft time, double that and take it off your existing 1/4 mile time.

Good to see you going for a goal. Im sure youll get there fast once you get more time in the car and so some little mods to help.

Awsome on the headers!! Thats a good way to let her breath better. Thats a great addition to what you have going so far.

Some may dissagree but in my own exsperience the underdrive pulleys are not worth it for the bang they add. Other things like a cam or such would help much much more if you able to do those sorts of mods? Or gears as your 2.77's are holding you back im sure of that.

 

I would love steeper gears, I have a 9 bolt rear so that's what sucks. I think 3.42s would wake it up nicely I just need a new carrier and they are hard to find

 

Any big tube runner and base upgrade or a short runner intake like miniram stealth ram superram etc will show big gains but you need a sticky tire to really show what its capable of

 

gears would be the best thing. for it at this point.

get some taller tires would add some MPH to it also

 

3.73s, LCARBs, 160 t-stat, manual fan control, 8-10 degrees of timing, and sticky tires.