Tremec Magnum T-56 Street car use Occasional Drag, 2.66 or 2.97 first.

[ricardoa1]

Hello gang. I have a question you guys maybe from experience might help me grab the correct ratio.

T-56 Magnums come in two gearsets as you might know.


2.66 1.78 1.30 1.00 .80 .63 2.90

2.97 2.10 1.46 1.00 .74 .50 2.90



The car has about 27" tires. And will make about 450RWHP with a very wide 430WFT/lbs Twin screwed, It will weight about 3850-3900lbs with driver. And its mainly a street car that spends alot of time on the highway and does long trips from time to time. It needs to perform well on the 1/4" but thats not the ultimate goal. Id like to keep the revs around 2k at a cruising speed of 75-85 for mileage. On the nitrous on E/T drags or full slicks and a 50-75HP shot it needs to make a pretty good 60ft. And the occasional corner carving. Oh and redline is about 6500 but can wind up to 69-7000 but does not make much power up there. It peaks about 6200rpms.

With these detail what Magnum would you choose?




Here are some multiplications based on rear end.

2.97 3.55 10.54
2.10 3.55 7.46
1.46 3.55 5.18
1.00 3.55 3.55
0.74 3.55 2.63
0.50 3.55 1.78

~ 1,900 RPM's @ 80 MPH in 6th

2.97 3.73 11.08
2.10 3.73 7.83
1.46 3.73 5.45
1.00 3.73 3.73
0.74 3.73 2.76
0.50 3.73 1.87

~ 2,000 RPM's @ 80 MPH in 6th

2.66 3.73 9.92
1.78 3.73 6.64
1.30 3.73 4.85
1.00 3.73 3.73
0.80 3.73 2.98
0.63 3.73 2.35

~ 2,500 RPM's @ 80 MPH in 6th

2.66 4.10 10.91
1.78 4.10 7.30
1.30 4.10 5.33
1.00 4.10 4.10
0.80 4.10 3.28
0.63 4.10 2.58

~ 2,800 RPM's @ 80 MPH in 6th

 

[BruceH]

2.97 and you will probably want 4.10's in the back.

 

[ricardoa1]

Thank you for the feedback. Im not sure if 4.11s will be too much for use with a 2.97 first gear.

I always heard that a good launch gear multiplier should be around 10. This is for street/strip.

2.97x4.11rear=12.2067 for a total 1st gear. I feel like thats too much for a street car.
2.66x4.11rear=10.93 this is what the 03-04 cobra guys use for some good 60ft numbers. But I dont think I even want to use 4.11s rears on either boxes.

Any thoughts?

 

[BruceH]

I can tell you that I'm running 4.10's with a Tremec 6060 that has a 2.97 first. It's about the same ratio as a standard Tremec 3650 with 3.55's. If 4.30's didn't have the bad noise rep I'd put those in.

Why are you going with the T56 Magnum instead of the S197 Magnum or a GT500 6060?