Rear gear ratio advice

[GS455vert]

I have a 67 Chevelle with a 2006 Corvette 6.0 LS 2 in it, the trans a 4L 60 E and I plan on doing a 2600-2800 stall converter and camshaft swap. The vehicle has a few upgrades and makes around 500 hp. I’m looking for rear gear ratio advice. Wondering what a good “trade-off“ ratio is. This is a weekend car and thinking about either at 3:55 or 3:73..

[69cutlassrkt]

I vote for 3.55:1. If it's a weekend car it will be more fun with a higher stall torque converter say around 3600-3800. I wouldn't buy one of those rebuilt converters that have the fins bent to increase the stall speed. Get a nice one like a 9" converter with a billet front cover. The shift extension will be better with a looser converter especially with that big drop from 1st to 2nd gear.

[68Formula]

You didn't mention the camshaft. But, sounds like you won't be doing a ton of highway. I vote for the 3.73s. The .696 final drive would keep you cruising <2500 even at 70mph. Should make it really more responsive and fun even with the mild stall.

Circle has a budget 278mm (11") 3000-3200rpm budget convertor with anti-ballooning plate. Make sure you have a large trans cooler if you're putting all the power to a 4L60E.

[69cutlassrkt]

You didn't mention the camshaft. But, sounds like you won't be doing a ton of highway. I vote for the 3.73s. The .696 final drive would keep you cruising <2500 even at 70mph. Should make it really more responsive and fun even with the mild stall.

Circle has a budget 278mm (11") 3000-3200rpm budget convertor with anti-ballooning plate. Make sure you have a large trans cooler if you're putting all the power to a 4L60E.

I agree, that rpm at 70mph isn't bad. Where I live I usually drive 75-80mph on the highway. Good advice on the trans cooler especially with a looser converter.

[ULTM8Z]

I vote for the 3.55 as well. With my 3.42 and 700R4 (same gear ratios as the 4L60) I'm doing about 2400 at 70 mph.

And BTW, if you really want to have some fun with that thing, stick a gear vendors OD behind it. Eight gears... it is SUCH a blast...

[68Formula]

Only about 100rpm differential cruising in overdrive between the two. But the part throttle tip-in and acceleration will be a noticeable. Go for the 3.73.

[mean buzzen half dozen]

Depends on what diameter tire are you going to use. 26" tall? 3.5 , 28" tall 3.73

[Interceptor5588]

Yup, very true. The deep 3.06:1 first gear of the 700r/4L60 was designed by GM to get cars moving off the line, making them feel peppy even way back when 305's were roaming the earth. A modern car with lots of power, 3:73's and 25" tires will be spin city in first gear. 27-28" tires, not so much.

[Zspoiler]

I have had good luck with 3:42 gears .
;

[GS455vert]

going with 3:55 gears. Doing a cam upgrade and a Coan 2800 stall converter, should have plenty of gear while still having good OD RPM

[69cutlassrkt]

By the way it's a ratio of 3.55 to 1(3.55:1) not 3 to 55(3:55). The drive shaft turns 3.55 times for every turn of the wheel.