What gears to run with th400 car?
#1
What gears to run with th400 car?
Hey guys I have a 99 z28 with a 408ci and 200 shot and I'm seeing what would be a better gear choice either 3.25 or 3.50 I rarely hit the track but I want something that's gonna have good street manners and don't want to be turning 3000 rpms at 65mph. I currently have 3.70's and I run 28" tires and car has a 3600 stall. I mostly mess around on the highway. Lmk guys thanks.
#4
TECH Enthusiast
iTrader: (5)
With a 408 and 200 shot you won't make it through the 1/4 mile now.
With a 3.25 gear, 8% slip on the converter, and 6500 rpms that's about 152 mph
With a 3.50 gear, 8% slip on the converter, and 6500 rpms that's about 142 mph
With a 3.70 gear, 8% slip on the converter, and 6500 rpms that's about 135 mph
I am running a 3.70 with home ported 241's, TV2 cam, th400, PTC 3500 converter. I have not had it at the track yet but plan to spin to 67-6800. This should give me about 138 mph. You need to base it on mph you think you can achieve at the track. Or just pick based on the cruise rpms you want. At 3200 I'm at 65 mph but on a 26.5" street tire. Since my converter was speced for a 28 when I race the converter tightens up on the street tires. Still turn right at 3200 at 65 mph if I run the 28s on the street because the converter slips more. Point is if you put in a taller gear(numerically lower) with out changing the stall the stall will loosen up and be less efficient.
With a 3.25 gear, 8% slip on the converter, and 6500 rpms that's about 152 mph
With a 3.50 gear, 8% slip on the converter, and 6500 rpms that's about 142 mph
With a 3.70 gear, 8% slip on the converter, and 6500 rpms that's about 135 mph
I am running a 3.70 with home ported 241's, TV2 cam, th400, PTC 3500 converter. I have not had it at the track yet but plan to spin to 67-6800. This should give me about 138 mph. You need to base it on mph you think you can achieve at the track. Or just pick based on the cruise rpms you want. At 3200 I'm at 65 mph but on a 26.5" street tire. Since my converter was speced for a 28 when I race the converter tightens up on the street tires. Still turn right at 3200 at 65 mph if I run the 28s on the street because the converter slips more. Point is if you put in a taller gear(numerically lower) with out changing the stall the stall will loosen up and be less efficient.