h/c c6 vs procharged 96 cobra
#101
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They are. Car blows right threw the meat of the tq curve. There were guys at the track back when these cars were newer with 4.10 and they would never be more than .1 quicker and would have 1mph less than me with 3.42.
For example my car makes about 340wtq @ 2000 rpm, peak of 405 and it don't drop below 360 clean to 6800. No need for alot of gear with broad tq like that. 3.73's probally would not change performance and may help it. Could also be the reason it went quick/faster with a change to a 3.90. I could've turned the limiter up a bit as it was @ 6800(7000 now) back when I had 4.10's or put a taller tire on, but I never felt the 4.10's loaded the car very hard. They just did alot of revving.
Maybe this is why my car runs like does. I don't just throw **** at it because of what others do.
For example my car makes about 340wtq @ 2000 rpm, peak of 405 and it don't drop below 360 clean to 6800. No need for alot of gear with broad tq like that. 3.73's probally would not change performance and may help it. Could also be the reason it went quick/faster with a change to a 3.90. I could've turned the limiter up a bit as it was @ 6800(7000 now) back when I had 4.10's or put a taller tire on, but I never felt the 4.10's loaded the car very hard. They just did alot of revving.
Maybe this is why my car runs like does. I don't just throw **** at it because of what others do.
#102
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Your not taking into account that the taller geared car stays threw peak tq longer....thus applying more tq over a certain period. Like I said I could've raised rpm with the 4.10, but the car would've been past the best power range to keep the car accelerating hard. More gear also uses more power. You did not factor that into your math.
#103
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Well im still not agreeing. For sure you cannot go to one extreme or the other. your not taking into acount the gear change either. You have to change to the next gear earlier with the lower gear which leaves a split second for the taller geared car to have more gear multiplication. It's not as simple as simple math. When I first changed gears in my car years ago we had a program we plugged my Dyno #'s in to chart acceleration with the gear splits. The stock gear(3.42) & the 4.10 charted to 150mph in the same time. The 4.10 of coarse took off faster but from 80 on the 3.42 started accelerating better.
#104
Well im still not agreeing. For sure you cannot go to one extreme or the other. your not taking into acount the gear change either. You have to change to the next gear earlier with the lower gear which leaves a split second for the taller geared car to have more gear multiplication. It's not as simple as simple math. When I first changed gears in my car years ago we had a program we plugged my Dyno #'s in to chart acceleration with the gear splits. The stock gear(3.42) & the 4.10 charted to 150mph in the same time. The 4.10 of coarse took off faster but from 80 on the 3.42 started accelerating better.
LOL at gear being a "tuning tool". . Some people have to sound so car savvy.
#105
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Maybe for your application you didn't see desired results. But when my car was stock with nothing but original SLP mods (blackwing/cat-back) I saw a consistent .2 gain in the 1/4 with 4.10's. With my experience with the LS6 loving high-rpms I wouldn't run anything less than 3.90s with a T56.
LOL at gear being a "tuning tool". . Some people have to sound so car savvy.
LOL at gear being a "tuning tool". . Some people have to sound so car savvy.
Hihoe- to put it to where you can understand it. Use this calculator. I think the math might be a little too indepth. But pick any referencable car from the drop down. There is a c6 so the hp and weight is probably close to yours. Do a test with 3.90's then 4.10's. Once you hit calculate it you can see the metrics for the different mph intervals (speed vs time, acceleration vs time, distance vs time). You'll see that in all the categories the 4.10's are quicker in every aspect including 80-120 that you said the 3.90's were.
http://vlsicad.ucsd.edu/~sharma/Potpourri/perf_est.html
#106
Your not taking into account that the taller geared car stays threw peak tq longer....thus applying more tq over a certain period. Like I said I could've raised rpm with the 4.10, but the car would've been past the best power range to keep the car accelerating hard. More gear also uses more power. You did not factor that into your math.
#107
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I rev limit it to 7000 stoppy. The engine carries the peak power out flat. Lower gears use more power because they turn faster. That uses power and creates more heat and/or the some power gets disapated as heat. Lots of guys have lost rwhp from changing gears/rears.
Bite I could not get the website to work, maybe because I'm on google chrome. All I can tell you is the change from 4.10 to 3.90 was a noticeable seat of the pants difference that showed up greatly at the track. Like I said the program we used on the race team I worked for the 3.42 was starting to be better above 80 and was alot better by 125. I have more faith in that software that we used to gear our hewland gearboxes vs internet download.
03turbomach and I set the rear up and we both noticed the difference. It just seemed like it pulled harder everywhere. Actually loaded the motor instead of just revving. Track times confirmed it.
Bite I could not get the website to work, maybe because I'm on google chrome. All I can tell you is the change from 4.10 to 3.90 was a noticeable seat of the pants difference that showed up greatly at the track. Like I said the program we used on the race team I worked for the 3.42 was starting to be better above 80 and was alot better by 125. I have more faith in that software that we used to gear our hewland gearboxes vs internet download.
03turbomach and I set the rear up and we both noticed the difference. It just seemed like it pulled harder everywhere. Actually loaded the motor instead of just revving. Track times confirmed it.
#109
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They are. Car blows right threw the meat of the tq curve. There were guys at the track back when these cars were newer with 4.10 and they would never be more than .1 quicker and would have 1mph less than me with 3.42.
For example my car makes about 340wtq @ 2000 rpm, peak of 405 and it don't drop below 360 clean to 6800. No need for alot of gear with broad tq like that. 3.73's probally would not change performance and may help it. Could also be the reason it went quick/faster with a change to a 3.90. I could've turned the limiter up a bit as it was @ 6800(7000 now) back when I had 4.10's or put a taller tire on, but I never felt the 4.10's loaded the car very hard. They just did alot of revving.
Maybe this is why my car runs like does. I don't just throw **** at it because of what others do.
For example my car makes about 340wtq @ 2000 rpm, peak of 405 and it don't drop below 360 clean to 6800. No need for alot of gear with broad tq like that. 3.73's probally would not change performance and may help it. Could also be the reason it went quick/faster with a change to a 3.90. I could've turned the limiter up a bit as it was @ 6800(7000 now) back when I had 4.10's or put a taller tire on, but I never felt the 4.10's loaded the car very hard. They just did alot of revving.
Maybe this is why my car runs like does. I don't just throw **** at it because of what others do.
...and LOL at you tooting your own horn "maybe this is why my car runs like it does"...I think everyone in this section knows who the king of but if when but but my car's a dd and this and that excuses is when you lose.
#111
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#112
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For a lot of people, one tenth would justify the gear change. Believe it or not, a majority of people don't race trap speeds like you do. At the track, it's who gets to the finish line first. You race trap speeds because your car "is set up for road races" or whatever you claim, so it is convenient for you to have an erection over trap speeds. You always claim what suits you (in this case gear giving you less trap speed at the track) is how it is "supposed to be". I seriously don't understand how someone like yourself can be so biased and not realize how biased you are. End of story. If you like roll races, less gear, track, more gear. Not everyone has the same taste as you...thought you would know this by now.
...and LOL at you tooting your own horn "maybe this is why my car runs like it does"...I think everyone in this section knows who the king of but if when but but my car's a dd and this and that excuses is when you lose.
...and LOL at you tooting your own horn "maybe this is why my car runs like it does"...I think everyone in this section knows who the king of but if when but but my car's a dd and this and that excuses is when you lose.
#113
How do you figure "lots of guys have lost rwhp from changing gears"?
#114
#115
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That's what it felt like. Made it feel like it started to use the tq.
#116
A 9" will lose a tad amount of power due to the pinion being well below the ring gear centerline, thus increasing friction resulting in higher gear lubrication temps. With that said, you're looking at a 3-5% hp loss - very minimal. A gear swap in a stock 10-bolt like yours would probably see no decrease in power.
#117
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You do the math on 3-5% loss @ 400rwhp. Then please tell us what it is.
I have seen guys claim 3-8 on a 10bolt. Could've been the day or a different dyno but more gear will use some power.
I have seen guys claim 3-8 on a 10bolt. Could've been the day or a different dyno but more gear will use some power.
#118
My point is, you have a 10-BOLT. The 9" rear is a completely different animal in itself. With a 10-bolt your not going to lose much if any, a couple hp at most. And the gains you see in acceleration are well worth it.