moser gear ratio

[tiddlar]

Just got off the phone with moser, they suggested a 3.50 3.70 gear ratio..... A vendor im talking to suggested 4.11... let me tell you the plans, the tires are 29x18x20, t56 6 spd tranny, small block chevy twin turbo. the car will be mostly street with a couple passes at the track. i want to be able to take off the line... what are your thoughts?

[KQQL IT]

Would depend on the O.D ratio

[tiddlar]

Originally Posted by KQQL IT

Would depend on the O.D ratio

i couldnt tell you,, havent even thought of buying a tranny yet...

[Captainfab]

With the T56 having a double OD and with those somewhat tall tires, I'm thinking 4.11's would be better.

[tiddlar]

Originally Posted by Captainfab

With the T56 having a double OD and with those somewhat tall tires, I'm thinking 4.11's would be better.

I have been googling a lot and sounds like 4.11's would be good for my application. Thanks a lot for your input.

[tiddlar]

Pics

[tiddlar]

.pics

[tiddlar]

20x15's

[tranz am]

It really depends on what you want to do with the truck snd how the motor is built. Are you after milage and some performance, or more interested in performance alone? The opperating rpm of your motor will dictate your decision. With a t56 you can run 4.56 gears all day no problem and still get decent mpg in the overdrive gears. With drag racing you are not really going to want to shift into overdrive so that would be a factor to stay below 4.11 gears, you want to keep it in the first 4 gears for that.
If your motor is built to produce really strong low end torque you could run 3.42's and be getting mpgs in the upper 20's to low 30's!

[Marv D]

Number of different T56's ...
BORG WARNER T56-
2.66 - 1.78 - 1.30 - 1.00 - 0.74 - 0.50
2.97 - 1.94 - 1.35 - 1.00 - 0.84 - 0.62
3.36 - 2.07 - 1.35 - 1.00 - 0.84 - 0.62


but yup,, for performance being only 10 of the real use, and the gear ratios for a T56 I'd look at average town driving RPM and 4th gear tops (1:1) and out on the road using the OD gearing to get efficiency. (like a TT ride is a efficiency concern LOL)
Even at 85MPH on the highway you'd be 3600 in 4th, 3100 in 5th and 2300 in 6th with 3.73 gears and the 29" tire. I think You'd find 3.73 gears and 5th gear a 'happy place' at around 2700. ( You can add just about 300RPM for going to a 4.11 gear.

I guess the easy way to look at it is you can increase 300 rpm,,, or 10mph @ the same RPM difference between 3.73 and 4.11 gear

[hotrod 80]

3.73 or less would be my choice . Ant of the first gear ratios X the rear axle ratio = tire smoke

[tiddlar]

Originally Posted by hotrod 80

3.73 or less would be my choice . Ant of the first gear ratios X the rear axle ratio = tire smoke

i dont know if you guys saw the jay lenos garage video with the ring brothers chevelle? he kept complaining how short first gear was. most likely due to high gearing? i have a lot to think about. luckily i dont have to buy the ring and pinion at this very moment.

[hotrod 80]

4.10 x 3.36=13.77

A granny 4 speed first is 6.55 x 3.07 =20.10 Second gear is 3.58 x 3.07=10.99 Just to put it in prespective . Something to think about .

[tranz am]

Originally Posted by tiddlar

i dont know if you guys saw the jay lenos garage video with the ring brothers chevelle? he kept complaining how short first gear was. most likely due to high gearing? i have a lot to think about. luckily i dont have to buy the ring and pinion at this very moment.

Yea first gear for some of these od units are really short (2.97) if used with numerically higher rear gears. I had a t5 once with 4.56 gears that was only good for about 25-30 mph in first. Get a trans with 2.66 first gear for a longer first gear with higher ratio rear.

[BigDan3131]

But...he said twin turbo's so going with the 3.50 gears might be the best choice but then again which twins and how big or small are they. If their small, boost will build up fast and too much gear its tire smoke city[ it will be that way anyways with 20's]. IMO I would look at the Richmond 6 speed instead.

[Rannos]

With turbos I would go 3.55 or less. Plus its been my experience that you ask a suspension guy about suspension a head porter about heads and a cam grinder about cams. Asking the cam guy how to set your suspension doesn't seem to work out so well.

[tiddlar]

Originally Posted by BigDan3131

But...he said twin turbo's so going with the 3.50 gears might be the best choice but then again which twins and how big or small are they. If their small, boost will build up fast and too much gear its tire smoke city[ it will be that way anyways with 20's]. IMO I would look at the Richmond 6 speed instead.

a lot ot research and think about thanks guys