NEED HELP! what rear end gears for viper t56?????

[troysinclair]

Hi everyone, I recently bought a viper t56 for my 2000 saleen mustang. I am wondering on what rear end gears i should get for street strip use. Mostly strip though because i wont get traction on the street no matter what. My car is going to have a 4v procharger running 15-18psi. I am hoping to reach 800 hp. I am also going to purchase a fuel management system. But have no idea which one to get. If anyone has any opinions that would be great.

Ok so right now my t-45 has the following gearing.
1 - 3.37
2 - 1.99
3 - 1.33
4 - 1.00
5 - .67

My new viper has:
1 - 2.66
2 - 1.78
3 - 1.30
4 - .74
5 - .50

My current gearing is 3.73 rear end.
I want this car for good strip results as well as street.
I am thinking of getting 5.13 rear end but need advise.
i am not too sure if i should get higher or lower rear gears
lower would get out of the hole quicker and boost quicker, but also a short shift, but a longer 1st would do the opposite, but have a longer 1st gear.

I have also been thinking that if i go with 5.13 rear end I can use 2nd instead of first, and it would be close to a stock 1st. and i would still have a good overdrive for crusing. But i have not raced on slicks before , or on the strip and dont know if the low first gear will help me or slow me in the 1/4 mile?

I know on the street ill have to granny shift and be easy on the pedal no matter what, but i am wondering what to do with 12" slicks ubnder my car at the track. I would really appreciate ant help from people who drag alot. I really hope to get into the 10s next spring.

Thanks for any info or input.

 

[99SilverGT]

5.13? Damn. If you're really hoping for that much HP I'd go with 3.73, 4.10, or maybe 4.33... even with the viper tranny, but especially since you want Street/Strip. 5.13 gears would pretty much be slicks only IMO. Definitely not road traction.

 

[00s281sc368]

You forgot the 4th gear on your t56
To match the ratio of T45 with 3.73, you need more than 4.30 gears on your viper tranny. Just look at overall ratio below.
But if you make a lot of power, there is no reason to go too short, the 1st will be useless. You could use it with a longer ratio to push your car quickly to 50mph before shifting...


T45 with 3.73
1 - 3.37 = 12.57
2 - 1.99 = 7.4
3 - 1.33 = 4.96
4 - 1.00 = 3.73
5 - .67 = 2.50

My new viper has:
1 - 2.66 = 9.9 (3.73) , 10.9 (4.10) , 11.5 (4.30)
2 - 1.78 = 6.64 (3.73) , 7.3 (4.10) , 7.65 (4.30)
3 - 1.30 = 4.85 (3.73) , 5.3 (4.10) , 5.6 (4.30)
4 - 1.00 = 3.73 (3.73) , 4.10 (4.10) , 4.30 (4.30)
5 - .74 = 2.76 (3.73) , 3.03 (4.10) , 3.18 (4.30)
6 - .50 = 1.86 (3.73) , 2.05 (4.10) , 2.15 (4.30)

 

[madmatt]

I think I read that a 4.56 gear is a good one for the viper tranny.

 

[troysinclair]

Hello, thanks for the input, So a short 1st gear on slicks at the track would not benefit me? on the street it would be no problem to use 2nd to start with 5.13's. Ive never raced so i dont know. but I guess it would depend on how good of a shifter you are too. Any other opinions? or comments from people with drag cars, what overall ratios do mest people use when having a 10 sec standard car boosted with a procharger. remember, the faster i get up in rpm the more power i will make.

Ovarall ratios for 5.13 gears

1 - 13.65
2 - 9.13
3 - 6.67
4 - 5.13
5 - 3.70
6 - 2.57

this ratio would probally be close to a stock tranny running 4.10's plus on the street i could use 2-6 gears and use 1st for slicks only.

Thanks for your opinons and help.

 

[Jackie Chan]

my opinion is to ask a good tuner with knowledge on this subject...not us sn yahoos



edit:for track use I would go with the most gear i could for the 60' but of course letting car go through the traps in the highest rpm in the last track gear

 

[Cobra Jay]

I think I read that a 4.56 gear is a good one for the viper tranny.

Yes 4.56's are good for a Vipers, but that's also considering the Viper is N/A .


4.56's or 5.13's<---- would actually make you go slower. You'd be shifting almost as soon as you let your foot off the clutch.


4.10's or even 4.30's would be perfect with the set up you're running.

BUT, If you're planning on running mostly on the strip, why did you go with a T-56 6 speed insted of re gearing your T-45?

 

[troysinclair]

hello ,I did buy a viper 6spd. Thanks for the input though.

 

[Cobra Jay]

hello ,I did buy a viper 6spd. Thanks for the input though.

No $hit, My ? was WHY?

If you're going to be running on the strip mostly, WTF do you need a 6spd for? DUH!

 

[madmatt]

Added strength?

 

[DBMSTNG]

i say keep the 3.73's. with anything more than that, you'll be doing alot of shifting. just my 2 cents.

 

[Cobra Jay]

Added strength?

He could have beefed up and changed the gearing in the T-45 or went with a HiPerf. AOD with a high stall converter for A LOT less than the cost of a Viper T-56. That's what I would have done.

 

[FallenPhoenix]

I'm guessing the T56 is for a little better gas mileage on the highway for pure strength and track only use the T56 would not be my first choice.

 

[FallenPhoenix]

I'm guessing the T56 is for a little better gas mileage on the highway for pure strength and track only use the T56 would not be my first choice.

 

[nf9648]

2000 Cobra R had 3.55 with a T56, if you already have 3.73's I would stick with them.

 

[troysinclair]

Hey everyone.

you cant compare the viper t-56 to the cobra t-56, the gearing is way different. I guess what i need to know is what ratios do guys use on the track with the t 45 or tremec 3650 or even the cobra t-56. I can figure it out on my trannys gearing from there.

I bought the viper t-56 because of the benefit of the .5 overdrive for hwy, as well as the fact it is a close ratio tranny, and it is strong and i only paid 900$$$ for it. I can run 5.13 gears and still get a similar overall overdrive gear as i do with my t-45 and 3.73's

 

[5.0's 4 ever]

If you plan on going through the traps in 4th gear then having a viper t56 doesn't really matter over a t45 unless you are that concerned about the difference in the first couple of gears. My car is not set up for drag racing but when the time comes it could hit almost 130mph in 4th gear with 4.30s and 26" tall tires.

 

[hotmustang331]

I would stay with 3.73s, because since it is a close ratio transmission, you need a little highend gear so you can pull through every gear...the close gears in the tranny will do the rest...BTW the T56 is a good motorsport tranny, like auto cross or the trans am series and crap, the close gearing allows you to pick a gear thats right for any corner, and the engine will never be out of its power band, IF the correct gear is chosen.I dont believe it was ment for 1/4 mile racing due to its high 1st gear, but racers use it because of its strength, and because they can take car of the high 1st by simply dropping in super low gears.If your goal is to be VERY fast, go with a tricked auto, 3500RPM stall, and trans brake.