Rear gear change?

[TommyP]

I'm kind off kicking around the idea of changing my rear end gears while I have the thing apart. Currently I have 4.10 gears but am thinking about switching to 3.73's to make the car more streetable. Any guesses on how much my 1/4 mile times would change going from 4.10's to 3.73's? Has anyone heared anything bad about the 3.73 gears made for the series 4 carriers?

[dbreese]

Hi, Tom

 

US Gear, Yukon and I think Richmond make a 3.73 gear set for your series 4 carrier. As far as performance I can't say for sure but I'm thinking that my old engine and your current one are pretty close and I would think yours makes more power. I think the difference is the converter. I had 3.73's in my old combo and in good air it would run 12.30's. I know ya may not want to go with a custom converter but it can really wake up a car if matched with your current combo.

 

David

[TommyP]

Hey David, The idea of the 3.73's are for Dragweek to try and make the drive a little easier but I talked to a guy this year at the finals that did it with 4.10's and the same size tires,might just take a little longer,ha ha.I would love to get that Coan converter still if I can swing it. Keeping my fingers crossed!!!

[Winston Wolf]

First of all Tommy, none of this is directed towards you, it's a general statement.

 

I would leave them. If I recall correctly, it was worth 1.5-2 tenths in my car.

 

4.10's are not the end of the world. People are just so used to OD transmssions and low RPM's that they forgot about how things used to be. My cousins GTO came with a 3.90 gear stock, and they ran 25-26" tires. You could even get 4.33's from the factory.

 

Watch 2 Lane Blacktop once. They run 4.56's and drive across the whole USA.

 

Then people try to make you think that if you run a low gear that the wear on the drivetrain is so bad that the car will only last 2k miles. That's simply not true. I can tell you I've had my car for 16 years and put 40k miles on it. Some years it was zero miles. More stuff wore out due to not driving it than driving at 3k ever would.

 

Ask the guys that drove muscle cars back in the 60's and early 70's what they did. The guys that ran G60's, J60's, N50's and H50's on their old Chevelles, GTO's, Impala's and the like. They ran deep gears and 3/4 race cams and there was no such thing as OD. I never heard my uncles complain about too many RPMs at 55, and maybe that's where I learned it from. The fact is, lower gears, better acceleration. Gear it so the engine is maxed out at the end of the quarter, that's the best gear.

 

I will admit that you can get better gas mileage with lower cruise RPMs, no argument there. But if that's your goal, perhaps you are in the wrong hobby.

 

I've said it before, I have tried almost every gear ratio out there. For me with a 3 speed trans and a small block, 4.10's is the ticket (for a performance car).

 

Don't fear 3000 revolutions per minute.

 

Heed the words of Wooderson "Let me tell ya what Melba Toast is packin right here alright, we got 4.11 posi track out back, 750 double pumper, Edelbrock intake, bored over 30, 11:1 pop-up pistons, Turbojet 390 horsepower, we're talking some f'ing muscle."

 

And stay thristy my friends.

[TommyP]

Yeah, the more I think about it the more I think that I'll probably leave it as is. It would drop the RPM at 60mph about 300 RPM but I have a lot of other areas of the car that I want to put some money into ( like that converter) and there is only so much to go around. Thanks for the info.

[680HPStroker]

As long as you have the right stall speed don't sweat it. I run 4.11 gears on the street and have for over 4 years now with zero drive train issues. If you don't mind the the revs buzzing you you will be fine.