rear gear ratio
Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 15
Likes: 0
rear gear ratio
I have a 74 vette with a 350 motor out of a 79 van. It has a performer intake, 600 holley and headers. the rest is stock as far as I know. The rear gear is a 3.08. It has a turbo 400 trans and a 2000 stall. I would like a little more bottom end performance without killing the gas mileage. The car is a toy and not something that gets driven every day. The rear needs to be rebuilt and while I'm at it I was thinking of changing the rear gear. I thought maybe a 3.56 or 3.70 would be a good choice. The car runs high 14's in the quarter in the mid 90's. What do you thilnk? Greg
Intermediate
Joined: Feb 2013
Posts: 28
Likes: 0
From: Birmingham Alabama
Decide (be honest) how much 70 MPH+ interstate driving you'll be doing.
Find a RPM calculator that lets you enter tire size, etc. and find a confortable cruising RPM based on how you define 'cruise'.
My '79 T/A has 3.23's and my '84 MCSS has 3.42's, each with a non-OD trans.
70 MPH is 'okay' but 80 MPH begins to draw me up as the tach is really winding up there.
Cruising around side roads at 55 MPH max, I'd take a set of 3.73 gears all day long.
Find a RPM calculator that lets you enter tire size, etc. and find a confortable cruising RPM based on how you define 'cruise'.
My '79 T/A has 3.23's and my '84 MCSS has 3.42's, each with a non-OD trans.
70 MPH is 'okay' but 80 MPH begins to draw me up as the tach is really winding up there.
Cruising around side roads at 55 MPH max, I'd take a set of 3.73 gears all day long.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Any gear steeper than a 3.36 will cause the car to turn more than 3000 rpm on the highway. No problem for short distances...but hot, noisy, engine-taxing for longer trips.
But, you know what you want. Your call....
But, you know what you want. Your call....
