Hi all,
I was considering a gear swap on my '87.(2.59 to 3.07 or @ the most 3.54). I love the low/mid range torque on the l98 but want to improve a little. I know it has a narrow power band and I don't want to be in and out of it too fast.
Some people tell me to leave the gearing as is and swap the converter while others tell me to go with a lower gear.
Any opinions from the experts out there?
By the way the car is 100% stock.
Thanx

 

With a bone stock TPI & A4 you are likely shifting at 4,800rpm so I suggest both a 2,000-2,200rpm TC and a TransGo shift kit.

 

If its one or the other, get the 2000-2200 rpm TC.

Add a tranny cooler as well.

 

Is both o.k. as long as I don't go too low on the gears?

 

I would only go to 3.07s on the L98, no lower.

 

If you drag race, change the converter. Although the converter is only effective off the line, it will cut your 60' times and ETs dramatically, more than gears. If you don't take it to the strip, do the gears.

RACE ON!!!

 

Yes.
As Vader said 3.07 max for TPI, as CFI said TC for dragging, gears for street. But a TC and gears are a lot more fun on the street, so do both if you can.

 

As mentioned above with the TC also install a trans cooler as the higher stall will build up more heat in your 18 y/o tranny. (or even a new tranny)

 

Use a calculator and figure out which gear you would want at the trap speed your run at at the track.

I picked mine out perfectly and dropped a half second in the 1/8th with no changes other than a gear. Car runs threw the traps at 6k RPM and stays between 4.9-6k the entire time.

 

I have an '88 with 2.59 gears with bone stock engine. It ran consistant 14.60's with drag radials. A couple weeks ago I had the tranny rebuilt for high torque (500-600ft lbs) and installed a 2400 stall converter in anticipation of a new engine I ordered yesterday. But I wanted to see the performance change for just the converter so off to the drags with drag radials again. Automatic shift rpm's were left stock, like 4600, just stick it "D" and floored it.

At 175 to 185 degrees engine temp, the car ran a 14.14 twice and cut .20 off its prior 60' times to 2.0h's. When the engine warmed to 200-205 degrees, the car ran 14.30's at 2.teen 60 footers. (I made a total of 7 passes) The upgrade in tranny internals had no impact on these times as it shifted normally, it is just internally much stronger. Full throttle automatic shift points will get changed with the new engine, like to about 5800.

All these times (before and after) were from a deep stage position. The "lock up" feature still works in third and O-D, so there is no impact on highway mileage. I am delighted, but the engine does rev a bit higher in 1st and 2nd (normal driving) than I like (particularly 2nd). When I install the new engine, I might have the converter adjusted to 2000-2002 rpms. I have not decided for sure yet. The converter changed the character of the whole car.