The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   LSx Swaps (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=206)
-   -   gearing opinions (https://67-72chevytrucks.com/vboard/showthread.php?t=419460)

mfl1 09-01-2010 08:26 PM

gearing opinions
 
hey guys I am trying to get parts together for my swap. Heres what i have 6.0,4l80,and a rear out of a 96 impala ss. It has 308 gears stock, but i have 305/40/22 tires and thought a lower gear may be nice. I'm not drag racing just crusing and some towing use. thanx in advance.

cableguy0 09-01-2010 09:19 PM

Re: gearing opinions
 
You definately need more gear. I wouldnt run anything smaller than a 3.42. Those tires are almost 32 inches tall. I would personally use a 3.73 and possibly a 4.10 if it wasnt being driven much.

Super73 09-02-2010 12:55 AM

Re: gearing opinions
 
I drive a 30" tire with 4.56's on the street on a regular basis. The lock up verter helps a ton with my loose 4,500 stall. A stock stall would show a smaller drop in RPM by engaging the lock up. I see 2,475 rpm at 65mph. Remember, the 80E's has a tall first. A steeper rear gear makes things nice.

My wife's trailblazer SS has a factory 4.10 gear and a 29" tire from the factory. It cruises at 2,300 at 65mph. I use the wifes TBSS to tow the race truck to the track (3600lbs + 1500lbs = 5100lbs + gear)

If I was rocking a 31.5" tire (which is what a 305/40/22 comes out to) I'd probably opt for a 4.30.. This would put you at 2,250 rpm. Or a 4.56 would put you at 2,375.


Your not really going to loose a ton of mileage as your still keeping the motor in a very efficient range. If anything, you might actually pick up a little since your putting such a tall tire on it with such a tall gear and no longer lugging it.


BTW, a 3.08 with the tire you want to run would put you at 1,600 rpm..

Ackattack 09-02-2010 01:38 AM

Re: gearing opinions
 
My 05 silverado had ~32" tires on it with 3.42. I used it to tow my ~6500lb camper with. It definatly would have been better to have 3.73s

mfl1 09-02-2010 10:55 AM

Re: gearing opinions
 
wow 1600 haha. I was thinking a .373 but wasnt sure that was enough


All times are GMT -4. The time now is 05:46 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com