• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

T-5z and Rear Gear Ratio?

  • Thread starter Thread starter 93gtmustang
  • Start date Start date Jul 1, 2008

93gtmustang

10 Year Member
Oct 21, 2006
524
43
49
Jul 1, 2008
#1
  • Jul 1, 2008
  • #1
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 /
 

93gtmustang

10 Year Member
Oct 21, 2006
524
43
49
Jul 1, 2008
#2
  • Jul 1, 2008
  • #2
anyone?
 
A

abomb

New Member
Jul 1, 2008
0
0
0
Jul 1, 2008
#3
  • Jul 1, 2008
  • #3
what is your tire size? And do you plan on making more power in the near future? that would also change your decision....
 

93gtmustang

10 Year Member
Oct 21, 2006
524
43
49
Jul 2, 2008
#4
  • Jul 2, 2008
  • #4
abomb said:
what is your tire size? And do you plan on making more power in the near future? that would also change your decision....
Click to expand...

My tire size is 26x9.5
I would eventually like to get a 347 Stroker short block, but with money issues, that won't be happening for a long time
I'll be sticking with what I've got for quite a few years.
Thanks
 
You must log in or register to reply here.

Similar threads

Drivetrain 5th Gear Ratio
  • PonyGTrider
  • Dec 8, 2025
  • Fox 5.0 Mustang Tech
  • 2
Replies
33
Views
1K
Fox 5.0 Mustang Tech Dec 31, 2025
Qtrhrse23
Q
C
Suggestions for rear diff gears - 1969 Mach 351W 4v
  • cfauvel
  • Apr 8, 2024
  • Classic Mustang Specific Tech
Replies
10
Views
2K
Classic Mustang Specific Tech Jun 27, 2024
cfauvel
C
SN95 The Unicorn
  • HANO Motorsports
  • May 18, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
21
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 15, 2025
HANO Motorsports
SOLD SOLD!!!! 1993 Notchback Roadracer For Sale. She's a beast!
  • Boydster
  • Apr 25, 2025
  • Fox Body Mustangs For Sale (1979-93)
Replies
0
Views
1K
Fox Body Mustangs For Sale (1979-93) Apr 25, 2025
Boydster
Engine HELP - 351W Based Build Under Stock Hood
  • thinkfaster
  • Oct 17, 2024
  • Fox 5.0 Mustang Tech
Replies
13
Views
2K
Fox 5.0 Mustang Tech Dec 31, 2025
Qtrhrse23
Q
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?