rp0029

iTrader: (1)

I have a 68 camaro with a 3.42 rear gear (it is a 9.5" 14 bolt from a 3/4 ton truck, with the ends welded to fit the camaro). The LQ4 is almost complete, I want this to be a daily driver.

I can get 3.08 gears for the 9.5 on ebay. I know that it is a three series carrier, but is there a way I can get a numerically lower gear ratio on one of these rears without swapping the carrier? I don't want to do 2000 rpm at 60...

In the alternative, I've seen planetary sets for the 4l80e which raise (numerically) the gear ratio of 1st and 2nd gears. Does anyone know of a kit that will lower the overdrive gear?

futureuser

iTrader: (1)

With the 4l80 you will be at 2000 rpm at 60 with a 26 inch tire. You could just use a little taller tire.

Jim85IROC

iTrader: (6)

How low do you want your rpm at 60? 2k really isn't that high.

gofastwclass

iTrader: (2)

2000 RPM on the highway? I would say the gear you have is about perfect. If you notice where a lot of cars are at that speed you'll find them in that range for highway cruise. If you get much below that you lug the engine on hills or passing which hurts economy and if done enough, eventually the engine.

rp0029

iTrader: (1)

I guess I say this because my 99 trans am has 2.73s and a 4l60e (.67 ratio). It is actually perfect. It does about 65 at about 1500 and 2000 at about 75-80. When I whomp on it and it downshifts to third I take off, if I manage to kick down to second the tires chirp and it goes hard. My 99 was dynoed at 297 RWHP with a stock cam, tune, and headers. I love it. I can only imagine what my LQ4 with LS3 heads and a 222/230 cam with a full flowmaster exhaust + headers in my 68 camaro, which should put down 400-440 RWHP, will do. I don't really need any more gear than the 2.73. Spin city.

When I leave my 99 in third, I get about 55 at 2000. It is sort of annoying to spin 2500 at 75 mph. I don't want something like that. I'm building a driver. I supposed I could get 3.08s for this rear, but really, it would be like a 66 instead of 60 at 2000, so, probably not worth my time. But if I can get a 2.73 or even lower, it would be well worth it. I'm not worried about bogging on hills with 400 RWHP.

Kenova

iTrader: (4)

Don't forget that the new cam will move the torque curve higher in the rpm range. With 2.73 in the rear I would be willing to bet that anything below 60 mph you could have trouble keeping it in overdrive without it bucking and chugging.

Ken

Pop N Wood

iTrader: (1)

Depending on your cam such a light car works well with high gearing. My 2500# car runs I think 2200 RPM at 60 mph. I wouldn't mind something lower. the stock cam LS2 pulls so well I am in 5th gear by 35 mph.

Stu Cool

iTrader: (13)

I have a basically stock LS1/4l60e in a 3400 pound car. I have a 3.80 gear with a 28 inch tire. 65 mph is 2100 and seems quite comfortable. This works just fine, I get 27 mpg on the highway and the car pulls strong all through the mid range. If I were you, I would try it with the 3.42 first. It's something you can change later if you are not happy.

Pat

chrisfrost

iTrader: (8)

You're talkin about You're 99 being annoying spinning 2500 at 75 ,,,,,,,,,,,,in third ,,,why not then shift to 4th . I had a 80 Z-28 that I put a gov-lock with the stock 3.42's , a built 700 and basically stock engine with full duals and BFG 275-50-15's (26" tall) and I really loved those gears ,,,,,,,,,it was low enough 1st n 2nd to spin a little and in 4th locked up at 2500r's was cruising 85 mph ,,,,,,,,at 65 mph maybe 1800 r's ,,,,,,,,,,,perfect . But You've got a differential that weighs about 100lbs. , no maybe 50lbs. or so more in You're camaro ,,,,,should help some with traction . I hope You are'nt gonna have the rear jacked up ,,,,,,,,,,,,,,,,,bad spinning and handling and most importantly ,,,braking . put T/A big block springs in the front and rear stock height and have excellent handling, braking and better traction .