- Oct 21, 2006
- 409
- 15
- 29
I'm having a rear gear change done because my car is a dog out of the hole drag racing with the T-5z's 2.95 1st gear.
It's use to launch great with my old T-5 with a 3.35 1st gear and 3.73 rears.
But now it bogs and takes some time to wind up, even at 5k plus launches.
Does anyone here have a T-5z that they drag race with?
Just wondering what rear gear to go with.
I'm debating between 4.10's and 4.30's. I'd like to go with the 4.10's, but I don't know if that would wake it up enough, and then I'd have to pay for another gear swap for the 4.30's.
My average trap speed in the 1/4 mile is anywhere between 102 and 105 mph with the 3.73's depending on conditions and wind direction.
I used a gear ratio calculator and this is what I got for a trap rpm.
4.10's @102mph=5400rpms
4.10's @104mph=5500rpms
4.30's @102mph=5650rpms
4.30's @104mph=5758rpms
Also did a final ratio comparison for 1st gear.
My old T-5 with 3.35 1st gear and 3.73's =12.50
My new T-5z with 2.95 1st gear and 4.30's=12.69
My new T-5z with 2.95 1st gear and 4.10's=12.10
Current set up is T-5z with 2.95 1st gear and 3.73's=11.00
So I'm either at .40 under or .19 over my old set up that worked well.
I'm really leaning towards the 4.30's
Any suggestions would be great!
Thanks!
1993 GT Mustang / Ford Racing GT-40 Crate Motor B-303 Cam / 24 lb. Injectors / Stock Ignition / MSD EFI Blaster Coil / Edelbrock 5.0 Upper and Lower Intake with BBK Phelonic Spacer / Professional Products 70mm Throttle Body / C&L C.A.I. w/76mm MAF / Stock Air Box w/K&N Panel Filter / Holley Adjustable Fuel Pressure Regulator / Electric Fan / BBK Underdrive Pulley's / A.C. Removed / BBK Short Headers / Flowmaster Exhaust / Tremec T-5Z / B&M Short Throw Shifter / Alum. Driveshaft / 3.73 Gears / Eaton H.D. Posi / Moser 31 Spline Axles/ Subframe Connectors / Line Lock / Driveshaft Loop / B&M Short Throw Shifter / BMR Upper and Lower Control Arms / Lakewood Adjustable Drag Shocks/ Holley 190 lph Fuel Pump /
It's use to launch great with my old T-5 with a 3.35 1st gear and 3.73 rears.
But now it bogs and takes some time to wind up, even at 5k plus launches.
Does anyone here have a T-5z that they drag race with?
Just wondering what rear gear to go with.
I'm debating between 4.10's and 4.30's. I'd like to go with the 4.10's, but I don't know if that would wake it up enough, and then I'd have to pay for another gear swap for the 4.30's.
My average trap speed in the 1/4 mile is anywhere between 102 and 105 mph with the 3.73's depending on conditions and wind direction.
I used a gear ratio calculator and this is what I got for a trap rpm.
4.10's @102mph=5400rpms
4.10's @104mph=5500rpms
4.30's @102mph=5650rpms
4.30's @104mph=5758rpms
Also did a final ratio comparison for 1st gear.
My old T-5 with 3.35 1st gear and 3.73's =12.50
My new T-5z with 2.95 1st gear and 4.30's=12.69
My new T-5z with 2.95 1st gear and 4.10's=12.10
Current set up is T-5z with 2.95 1st gear and 3.73's=11.00
So I'm either at .40 under or .19 over my old set up that worked well.
I'm really leaning towards the 4.30's
Any suggestions would be great!
Thanks!
1993 GT Mustang / Ford Racing GT-40 Crate Motor B-303 Cam / 24 lb. Injectors / Stock Ignition / MSD EFI Blaster Coil / Edelbrock 5.0 Upper and Lower Intake with BBK Phelonic Spacer / Professional Products 70mm Throttle Body / C&L C.A.I. w/76mm MAF / Stock Air Box w/K&N Panel Filter / Holley Adjustable Fuel Pressure Regulator / Electric Fan / BBK Underdrive Pulley's / A.C. Removed / BBK Short Headers / Flowmaster Exhaust / Tremec T-5Z / B&M Short Throw Shifter / Alum. Driveshaft / 3.73 Gears / Eaton H.D. Posi / Moser 31 Spline Axles/ Subframe Connectors / Line Lock / Driveshaft Loop / B&M Short Throw Shifter / BMR Upper and Lower Control Arms / Lakewood Adjustable Drag Shocks/ Holley 190 lph Fuel Pump /
