JSDaddy189

88 camaro with 383 stroker weiand 144 with 7 inch pulley and 100 shot of the juice backed by a th350. My question is what's the best rear gear for drag racing? I'm currently running a 4.11 but have been told i'd get better results with something in the 3.42 to 3.73 range.

AlkyIROC

Too many factors to determine the best gear.

The "best gear" is a gear ratio that will get you across the finish line just as the shift light comes on. If you shift gears at 6500, your gear ratio will be different than an engine that shifts at 7000+ rpm. You can also use a slightly deeper gear and have the shift light come on a little before the finish line.

Car weight, engine rpm, tire size, converter stall speed can all change what gear ratio works best.

You need to make a good pass and see where the rpms are when you cross the finish line to calculate a different gear ratio. All the dyno simulators said my car's combination could use 4.56 gears. I swapped out my 4.86 for some 4.57 and the car hated them. Went back to the 4.86 and performance picked right back up. The 4.57 may be better but other things like converter stall and shift points needed to be changed to use those gears. My current combination of parts works perfectly with 4.86 gears so I leave them alone.

Go make a pass. If you run out of rpm before you run out of track with those 4.11 gears then you need to raise your shift point, install taller tires or change the gear ratio.

Orr89RocZ

iTrader: (20)

Yeah need to know what rpm the motor will be seeing as far as peak shift points. Also what tire size?

If car is making any decent power, 500-650 hp or slightly more, and its relatively normal weight it should trap 120 mph or so, somewhere in the 118-125 range my guess. That would do well with a 3.73 on a 26" tire and 6000 ish rpm. 4.11 seems too steep unless 28-30" tire maybe. Still dont need that much gear for a blower car on spray imo

JSDaddy189

Car has full interior so i'm guessing with me in it at least 3500lbs. Has a 2400 to 2600 stall with 28 inch tires. Blower is supposed to be done at 6000rpm. Only ran 1/8 mile and seems like I'm almost out of gear. I don't have money to be buying several gear sets so I want to get as close as I can on the first try. Also car is street driven regularly.

Orr89RocZ

iTrader: (20)

I would do a 3.42 then. Good compromise on street vs strip. I have that in my th400 car and 28"'tire. Wouldnt be bad for 6000 rpm limit imo