gear ratios and torque

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cudaFS

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Hello, question...how much rear wheel torque is lost from a 3:23 gear vs a 3:55 gear? I researched it to find the % of torque lost but the formulas and calculators are too complicated for me to grasp. anybody know the formula in ft lb not newtons?
thanks
 
Correct, lower gear makes a longer lever against the fulcrum point, multiplies torque.
 
thank you, I get the lower gear vs torque dynamic, I wanted to know what the difference was in %, @mopowers...did you calculate that with a proven formula or is it anecdotal?
 
thank you, I get the lower gear vs torque dynamic, I wanted to know what the difference was in %, @mopowers...did you calculate that with a proven formula or is it anecdotal?

(3.55-3.23)/3.23 = ~10%

In other words, 3.55's give you about 10% more torque multiplication as compared to 3.23's.
 
I'm cross posting this from another forum, Hello, question...how much rear wheel torque is lost from a 3:23 gear vs a 3:55 gear? everybody seems to concentrate on hp and 1/4 mile, but my car will be for old school light to light fun so in my way of thinking I'm using torque as my yard stick. I already have perfectly good 3:23's
Thanks
 
I'm cross posting this from another forum, Hello, question...how much rear wheel torque is lost from a 3:23 gear vs a 3:55 gear? everybody seems to concentrate on hp and 1/4 mile, but my car will be for old school light to light fun so in my way of thinking I'm using torque as my yard stick. I already have perfectly good 3:23's
Thanks

Mopower was good enough to give me the formula for figuring out for torque (3.55-3.23)/3.23 =10% of tq loss with gear changes. so here's my updated question...is the 53 ft lbs difference in torque worth worrying about? my engine wont be a dyno queen, I'm interested in real life performance not just high numbers
 
what is your car / engine specs and especially rear tire size? I'm going to try
2.94's and remove my 3.23's..still about 10%
 
what is your car / engine specs and especially rear tire size?

67 cuda 4 speed, 496 stroker, I'm still in the process of putting something together with Eric from MM so 550/hp 530? tq are targets current 3:23's 29 inch tire
 
with that much power you'll still have too much tire spin.Without practice and care a warm 318 A body with sure grip may out launch you at the lights
 
with that much power you'll still have too much tire spin.Without practice and care a warm 318 A body with sure grip may out launch you at the lights
all good info, I'm collecting as much info and variables I can to come up with my best combo, I appreciate your knowledge. Here's something you dont hear everyday...I'll have to shave some power off the engine lol
 
The correct answer is zero. The torque curved is moved. None is lost.
 
Want a wrench thrown in this.... if you have a torque converter, it may not make much difference. :)

The 3.23's work the converter harder than the 3.55's when accelerating. Load creates stall.
 
The correct answer is zero. The torque curved is moved. None is lost.
AAH, I never thought of that, got it. if the torque curve gets moved up rpm wise, will the 3:23's launch you with less force and give better traction off the line?
 
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My car is built for stoplights. With my 4.88 rear, spool and 295x65x15 slicks I leave the light like a raped ape. Just gotta be careful and roll into it or it will spin.

On a good clean street almost nothing can out 60 foot me. By 60MPH I'm out of the throttle anyway so the gear (top end) is a non issue.

I wouldn't hesitate to go even more gear for you like 4.10 or so, if you have enough tire to hook.(and you dont care about freeway driving.)

In my opinion nothing is more fun at a stoplight than a low gear, traction and power.
I live for the times when a new vett, hellcat, or mustang pulls along side and wants to play.
The look on their face at the next light is priceless!
 
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Want a wrench thrown in this.... if you have a torque converter, it may not make much difference. :)

The 3.23's work the converter harder than the 3.55's when accelerating. Load creates stall.

Hmmm, "load creates stall". What dat mean?
Once the engine has reached stall speed, and the car is moving, how does the converter come into play. Shouldn't the car accelerate faster with the 3:55's ??

Signed,
Confused
 
Stall is NOT a static number. A company can claim a TC stalls at 2500. Put that same converter behind a 400" 4" arm (500#/ft)and a 273" (325#/ft) stock stroke engine. Is the converter going to stall the same? Nope... 273 will stall lower.

Same with changing rear gear. 3.23's put more load, same as the 4" arm engine, on the TC.
 
3.55 - (minus) 3.23 = .32

.32/ (divided by) 3.23 = .09907121

Is that math correct?
dont ask me, It looks legit, I think I'll rephrase my question, is there that much of a difference between the 3:23's and 3:55"s? I can use the money somewhere else in the project if it wont. The engine's going to have gobs of torque any way
 
Stall is NOT a static number. A company can claim a TC stalls at 2500. Put that same converter behind a 400" 4" arm (500#/ft)and a 273" (325#/ft) stock stroke engine. Is the converter going to stall the same? Nope... 273 will stall lower.

Same with changing rear gear. 3.23's put more load, same as the 4" arm engine, on the TC.

Ok, still confused. I get that the converter may stall at a different speed depending on how much torque the engine is throwing at it. But say you have a 2500 stall converter, once you've met, or surpassed the stall speed rpm, isn't the lower gear going to give you faster acceleration at that point? Or are you saying that because the converter has less load on it,(because of the lower gears), that it will continue to slip more all the way down the track? I know that there is always a certain amount of slippage going on in a non lockup converter.
 
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