Why the HUGE stock/near mph differences?
Thread Starter
Staging Lane
Joined: Feb 2005
Posts: 90
Likes: 0
From: SW Ohio
Why the HUGE stock/near mph differences? My very tame 98 Z28 has gone 105 mph with a lid and FRA in low 70F temps. To me, in Ohio, at a track elevation of about 900 feet, that sounds about right. Other LS1 F-bodies we have seen run at the dragstrip for the last serveral years all seem to trap from 102 to 107 mph stock or nearly so. The higher traps are always the 6-speed cars, which seldom can cut a decent 60-foot, so they seldom get into the 12's around here.
I can understand that with the addition of a cutout, UD pulley, some better driving, and good air my car should get a 12.9 at 108mph and a 1.9 60-foot. But that is after adding over 40hp to the stock engine output -- and in a low-option 6-speed car.
But after poking around in the "12 second club" area for a while, it appears that there are cars with the same mods (or none) trapping 110-112 mph?!? Autos too?!?! Everyone knows that a manual car will have more mph than an auto -- less driveline loss. So what are the secrets to running these crazy high trap speeds?
Are these great runs made in Death Valley on a cold winter evening (DA-4000ft)?
Did the bragging owner remove everything that wasn't needed to drive down the track in order to drop weight (sat on a milk crate, no doors, three wheels and such) to unbelievable levels?
Was GM's quality control so bad on these LS1 engines that a variation of 100hp is possible between stock (or nearly so) F-bodies? That is the power difference between a 102mph car and a 112mph car, one I have seen, the other I have not -- but several folks seem to brag about them in the "fastest stock car" threads.
Or is my car (and most others) just "sick" and in need of some magical TLC? If so, please share the tips/tricks to gain trap mph.
Thanks,
I can understand that with the addition of a cutout, UD pulley, some better driving, and good air my car should get a 12.9 at 108mph and a 1.9 60-foot. But that is after adding over 40hp to the stock engine output -- and in a low-option 6-speed car.
But after poking around in the "12 second club" area for a while, it appears that there are cars with the same mods (or none) trapping 110-112 mph?!? Autos too?!?! Everyone knows that a manual car will have more mph than an auto -- less driveline loss. So what are the secrets to running these crazy high trap speeds?
Are these great runs made in Death Valley on a cold winter evening (DA-4000ft)?
Did the bragging owner remove everything that wasn't needed to drive down the track in order to drop weight (sat on a milk crate, no doors, three wheels and such) to unbelievable levels?
Was GM's quality control so bad on these LS1 engines that a variation of 100hp is possible between stock (or nearly so) F-bodies? That is the power difference between a 102mph car and a 112mph car, one I have seen, the other I have not -- but several folks seem to brag about them in the "fastest stock car" threads.
Or is my car (and most others) just "sick" and in need of some magical TLC? If so, please share the tips/tricks to gain trap mph.
Thanks,
I think alot of it has to do with weight....there's a huge difference in weights of these cars....my old 99 Z 6sp, weighed 3580 with 1/2 tank of gas and me in it with no parts removed .....it ran 13.60 @ 109 with a lid and exhaust.....!driver mod needed....
My 99 TA weighs 3760 on 1/4 tank with the spare/subs out...it runs 13.32 @ 105.xx on a 2.04 60' with a lid, cutout, headers, 3500 stall, and tuning on street tires....it's gone a best of 12.79 @ 107.17 w/1.801 60' on ET drags....with a race weight of 3690( skinnies and slicks were the weight difference )....this car started out as the atypical 14.00 second LS1....it's best was several 14.0X @ 99....
I bet alot of times it a combo of a good 60', fairly low weight, perfect shifting and some luck....I'd like to see if any of the fast runs were back to back and consistant....not just luck....
My 99 TA weighs 3760 on 1/4 tank with the spare/subs out...it runs 13.32 @ 105.xx on a 2.04 60' with a lid, cutout, headers, 3500 stall, and tuning on street tires....it's gone a best of 12.79 @ 107.17 w/1.801 60' on ET drags....with a race weight of 3690( skinnies and slicks were the weight difference )....this car started out as the atypical 14.00 second LS1....it's best was several 14.0X @ 99....
I bet alot of times it a combo of a good 60', fairly low weight, perfect shifting and some luck....I'd like to see if any of the fast runs were back to back and consistant....not just luck....
