Why so slow? '98GS


New Member
Took my 98GS (20,000 mi) to the track for the first time last week. Car is bone stock,93 oct.pump gas, took out dr. headlite. Expected around 15 flat. Got..15.75, 15.95, 16.2, then gave up! 60ft times were 2.35-2.5. Launched @1500rpm, both with traction control on once, and off twice. MPH was around 87-88 avg. car seems week if you nail it hard from a stop, but if you ease into the throttle off the line , it seems
to accelerate harder. Normal driving seems good (21-22 mpg around town). Any ideas as to where I could start looking for a problem? I'd like to get the car into the high 13's for now as it is my daily driver.
Scott and Robert, your cars seem to be running great! Good work! And thanks for sharing your mod's with us in true Buick"Go fast with Class" fashion!:(
I will be updating my web page with mods and progress of my new SC 3800. see test pipe thread.


I'm not an expert at problem solving. My car was 15.0 stock as advertised by the manufacturer. Have you checked your filters - fuel, air to make sure there are no obstructions?

Your 60 ft times are pretty slow even considering stock tires. Get stickier tires or just practice.

Where in MI did you run?

ICE! Ice down the SC for atleast 1/2-1 hr. When in the staging lanes keep the motor off AS MUCH AS POSSIBLE to keep everything cool. Take the intake hose completly off the TB, front tires about 22psi and rears max out, take out the spare tire and jack. Stay out of the water just do a light burnout to clean off the tires, Launch at 1500-2krmp and let the tires grab for a split sec. then mash the pedal. The ice took me from 15.2(hot engine) to 14.5:D - all stock.
Hmm, it definitely sounds like something isn't healthy, even if the 60' is bad, it should trap higher than 88. You might try resetting the computer, it might have picked up a bug or something. Or like Scott mentioned, check your filters and make sure nothing's stopped up. Hope you get it straightened out.
Thanks, everyone for the ideas! I'm figuring it's got to be something small (gonna change all filters first), then go from there.
I ran at Milan Dragway,Scott.
Thanks again guy's. I'll keep you posted.


Just an update on my 98' GS. I changed out the fuel filter(the air cleaner was fine) and the car definately seems to pull harder under WOT. Now if I could just get to a track to put it to the test. The tracks around here(Mi.) are now closed for the winter. If I could find a road around here without road construction I might be able to test with a Vericom.
While under the car, I noticed how bad(for perf.) the factory exhaust system looks. Does it choke as bad as it looks?
Thanks again for the idea's..................Al:D

In desperation,I called around and found a local track that was still open thru Nov. so out I went. The only change was a new fuel filter.... 1st run was 15.7@91mph...dr.headlite still in.(temps were about 55'. #2-removed dr. headlite...15.5 @92mph.....#3-same as #2(60ft.avg2.30...an improvement!)
Then while letting the car cool down I decided to remove the air filter. I got a surprise...thought I had changed the air filter a couple months ago but then realized it was my wifes car(DUH!) The filter was filthy! So, I removed it and pulled air thru the stock air box. I could feel a difference right away!
So to the staging lanes I went....and got a very pleasant surprise! How's a 14.6 @94mph sound !!! 60ft. was 2.13(t/c off). Then with the car heated up, I backed that up with 2 runs of 14.90..(no mph read-out) 60fts were 2.20 (t/c off ) & 2.25(t/c on).
Now that's more like it!
Thanks again for the sugestions,everyone! The little things one sometimes overlooks sure can add up( I still can't believe I did that!)
Now, on to my next upgrade...cold-air kit and pulley upgrade.
Which pulley set-up do you guys think seems to work the best? And which dia. pulley for a street-strip set-up?

I recommend the Dial-Ur-Boost pulley system starting with the 3.4. That way, you can switch pulleys quickly and without the need of a puller. When I pressed on my 3.4 pulley I said that was the last one I would ever do. Then I pressed on a 3.25 before getting smart and purchasing the DUB unit. Now, I go back and forth between the 3.25 for daily driving and the 2.9 for track use.

97.5 GS
13.024 @ 103.40
Scott, who sells the DUB system, and at what point will I no longer be able to use the stock serpentine belt?
Also, have you or anyone else had any experience with the ASE performance chips? Is this a plug-in chip similar to the Turbo Buicks? I'd sure like to firm up the shifts(which ASE claims it does)and get rid of the top speed gov.
While I'm on that subject, will it hurt anything to keep the trans in the "Perf Shift" mode continuously?

Thanks, Al
For the DUB, www.southfloridapulleyhq.com.

I believe you can go down to the 3.25 inch pulley before you should get a smaller than stock belt. I think I went to the Goodyear Gatorback 4060650 size with my 3.25 and it was real tight.

I haven't heard of any problems leaving the "perf-shift" mode on all of the time. I never turn mine off on purpose.

First, you send your PCM to ASE so they can unweld your chip. Then they insert their chip in a way that you can easily remove it and swap back the original chip if you want to ($30 if you want to keep your original chip). The few guys with the GS PCM have been pleased (originally, there were some problems, but those are resolved now). I suggest looking at the clubgp.com registry and searching for GSs that list a PCM upgrade. Those individuals either have the ASE or are one of a few with a Mecham PCM. Mecham is no longer willing to mod them.

Hope this helps.

97.5 GS