LS2, LLSR Chevelle 2-5-17 results
03-19-2017, 01:42 PM
#23
Nice Chevelle!
Your ET and mph are right in line with each other as well as your 1/8 mile to 1/4 mile ET comparison. You are picking up 22mph on the big end. As far as I can tell you are N/A so not sure why you think the car is not running out the back end. Seems fine to me. If you are running the 4l60 like your sig reads then you also have a 3.06 first gear when coupled with your 3.73 gear gives you the SLR equivalent of a 4.56 rear gear with a TH350 trans. More than enough to get you off the line. If you are running a 28" tall tire then it calculates you are ~ 13% converter slip at 117mph through the traps.
All in all it sounds like you have a very good running car for the weight and mods you have in that body style. MPH is a factor of horsepower to weight so I think if you want to go faster you will either need to lighten the car or make more power. If you are more concerned with getting the ET down you can do suspension and trans mods to launch harder. It's all a matter of what you want the car to do.
Just an observation, but in my opinion the most noticeable non drag racing part of the car is the trans. The 4L60E has a 3.06 first gear as I mentioned earlier and when you shift into second the 1.62 gear ratio is such a spread the engine/converter falls out of it's efficiency band. Not accounting for converter slip an engine shifted at 7100 rpm drops to 3760 on the 1-2 shift.
Good luck with the car. It sounds like a nice all around fun car!
Your ET and mph are right in line with each other as well as your 1/8 mile to 1/4 mile ET comparison. You are picking up 22mph on the big end. As far as I can tell you are N/A so not sure why you think the car is not running out the back end. Seems fine to me. If you are running the 4l60 like your sig reads then you also have a 3.06 first gear when coupled with your 3.73 gear gives you the SLR equivalent of a 4.56 rear gear with a TH350 trans. More than enough to get you off the line. If you are running a 28" tall tire then it calculates you are ~ 13% converter slip at 117mph through the traps.
All in all it sounds like you have a very good running car for the weight and mods you have in that body style. MPH is a factor of horsepower to weight so I think if you want to go faster you will either need to lighten the car or make more power. If you are more concerned with getting the ET down you can do suspension and trans mods to launch harder. It's all a matter of what you want the car to do.
Just an observation, but in my opinion the most noticeable non drag racing part of the car is the trans. The 4L60E has a 3.06 first gear as I mentioned earlier and when you shift into second the 1.62 gear ratio is such a spread the engine/converter falls out of it's efficiency band. Not accounting for converter slip an engine shifted at 7100 rpm drops to 3760 on the 1-2 shift.
Good luck with the car. It sounds like a nice all around fun car!
03-20-2017, 01:20 PM
#24
Thanks. It's actually a 3.42 rear gear and 275/50r15 tire which is around 25" tall.
Think it's just too much time spent looking at fbody times here. Seems I see a lot of the ls1 cars on this site trapping 95-96mph in the 1/8 are around 120mph 1/4.
I don't recall the shift extension off hand. I want to say during a run it doesn't fall below around 5,000rpm on any shift.
Think it's just too much time spent looking at fbody times here. Seems I see a lot of the ls1 cars on this site trapping 95-96mph in the 1/8 are around 120mph 1/4.
I don't recall the shift extension off hand. I want to say during a run it doesn't fall below around 5,000rpm on any shift.
03-20-2017, 07:02 PM
#25
Thanks. It's actually a 3.42 rear gear and 275/50r15 tire which is around 25" tall.
Think it's just too much time spent looking at fbody times here. Seems I see a lot of the ls1 cars on this site trapping 95-96mph in the 1/8 are around 120mph 1/4.
I don't recall the shift extension off hand. I want to say during a run it doesn't fall below around 5,000rpm on any shift.
Think it's just too much time spent looking at fbody times here. Seems I see a lot of the ls1 cars on this site trapping 95-96mph in the 1/8 are around 120mph 1/4.
I don't recall the shift extension off hand. I want to say during a run it doesn't fall below around 5,000rpm on any shift.
The shift extension engine rpm is also dependent on converter slip during the shift just like it does at the line launching so engine rpm will only drop to as low as the converter drags it down. Most likely when you first shift into 2nd you will notice rpm will climb slowly until the converter speed more closely matches the wheel speed and tightens up.
