My friend has a 1996 bonneville with 117k miles on it. he has a cold air intake and exhaust and the stock specs say 15.8 for the quater mile. we recently went to the track and he was running 17.3'* consistantly and managed to do a 16.9 once. we cant figue out why his car is so slow. does anybody know of any ideas or mods to help him, thanks

Check this out

http://www.bonnevilleclub.com/forum/...ode=cat&cat=18

That'* for mostly supercharged cars. I wish I could tell him to drop on a smaller pulley, but he can't.

It'* just so crazy that his car is over one second slower than it should be. I mean, my car when it was an L36 was way faster than his car. I drove his bonn at the track and it felt slower than my friends civic. I mean, it just has NO balls what-so-ever.

Oh, it'* an SE L36 and has zero options, so it should be lighter than something like an SSE.

any history of the O2 going bad? Maybe he'* got a partially clogged cat?

How about tune ups etc, cleaning TB and MAF ...stuff like that.

You could also optimize the TPS sensor.

Each car is a little different...he might own the dog and you had the road runner...

the 15.8 time is for the optional Supercharged motor that was availble in the SE in 96-97...his times are about right for a Series 2 NA.....you mention that he has a base model and possibly the 2.84 gear ratio which would make him slower yet....and options dont matter that much on terms of weight difference...maybe 100 lbs 150 max

dont see anything wrong with the times posted....

BonneMEMN had a lightly modded L27 for that run I believe, which would also have the taller gearing if im not mistaken, and even a lightly modded L27 isnt pushing the power of a stock L36...so im thinking there is definetely something wrong with that car, it should not be that slow in stock form.

Jason ran it, and i also ran high 15'* with the timeslips to prove it as did another L27....but ya...

and we dont know any info on the weather conditions (temp, track temp, and humidity) because that can cause up to a .3 +/- difference

100 to 150 pounds is actually very significant.


Or maybe the exhaust system is too big? More details regarding exhaust?

The cat is brand new (less than 2 weeks old). He replaced it because the car was so slow and has 116,000 miles on it. He'* also got a magnaflow muffler, but the stock resonator and stock pipes, so they're not too large for his car.

I cleaned the MAF off, and it was pretty dirty, so I guess that might help. He'* still got to test if it made a differeance.

The oxygen senser is probably stock, he'* never changed it.

He'* also got an intake (not true cold air, but it should still flow better than stock).

It does have a 2.84 gear ratio and a 2000 rpm stall torque converter, so that'* not helping him any. He does have, however, smaller tires and his speedo is pretty reading pretty high, so he should be equal to around a 3.06.

He also knows this guy with a 2000 Grand Prix GT, and it destroyed him. It wasn't even a close race.

Maybe it'* just a lazy motor???????????????