# 4 speed gears



## 1965goat (Sep 8, 2014)

Im getting a new 4 speed, and I can basically choose any gears for it, and I figure these are decent for dragging and the occasional highway. 
1st: 2.242:1
2nd: 1.948:1
3rd: 1.440:1
4th: 1.00:1
Are these decent? If not what would be some good close ratio gears? Thanks


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## PontiacJim (Dec 29, 2012)

Why not a 5-speed?


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## ibarbuckle (Feb 24, 2014)

Pretty close to the M20, which is either:

2.56 / 1.91 / 1.48 / 1.00 

or:

2.52 / 1.88 / 1.46 / 1.00

What are you running in the rear? I have a 4.11 with a 2.20 first gear, no problem. Why are your first and second so close together? Usually with a ~2.20 first you'd run ~1.60 second and ~1.30 third.


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## ALKYGTO (Mar 29, 2010)

PontiacJim said:


> Why not a 5-speed?


This. Unless Jericho......

Sorry. I'm gonna need way more information like car weight, engine combination and rear end gears. Everything has to be synced together to be harmonious. Get one thing wrong and your combination won't work to optimum and you'll fight it forever. Even a mild motor with the right trans and gear in a light car can be a great setup.


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## 1965goat (Sep 8, 2014)

*Update*

I have a posi rear with either 4.10 or 4.11 gears I believe and I refigured the trans gears and came up with these: 
2.242:1
1.615:1
1.338:1
1:1


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## 1965goat (Sep 8, 2014)

*Scratch that*

Refigured again and decided to go with gears similar to those of the 1967 Muncie m22. The new gears are:
2.242:1
1.615:1
1.287:1 
1:1

These are pretty damn close for the options I got to the m22. Any thoughts?


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## ibarbuckle (Feb 24, 2014)

Re-read alky's post. The M22 has the same ratios as the M21, different helix angles.


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## Chris-Austria (Dec 23, 2010)

I think a 5th gear with 0.70:1 would be nice to have if you run a 4.11 rear.
(I don't know if it's possible to have a 4th gear with a lower ratio than 1:1 or if it makes sense)

I have a 3.55 rear and the stock Muncie gears, I like it very much but even with my rear it needs a lot of rpm to drive faster than 60mph. Less rpm would increase milage + comfort and decrease engine wear.


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## 666bbl (Apr 13, 2014)

I've always felt that big TQ engines like a wider spread in the gears, like your 2nd choice, High RPM hyper engines that have narrow powerbands use a close ratio better in order to stay 'up there'. Your 1st choice had an unusally big spread between 2 and 3. Doesn't sound like much fun, like it would be boggy from 2 to 3 on a slow coast turn in normal driving.


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## geeteeohguy (Feb 2, 2008)

I'm with the 5 speed guys, or at least consider one of the special shift pattern Muncie's that has an overdrive top gear. I used to run 3.55 gears and anything above 55 mph was a chore. 4.11 gears would make your comfortable cruise speed about 45 mph. Pontiacs have a lot of torque, and don't need a high winding, steep rear gear for street duty. If you are dead set on using your 4.10.11 rear end, you should run an overdrive. Me, I'd swap the rear end for a 3.23, and stick a stock Muncie M-20 in it. As a side note, '64 and '65 Muncies had a stiffer 2.56 first gear than the 2.52 first gear of the later Muncies. Better off the line, by a hair. The early boxes also had a smaller diameter countershaft, which is not as strong as the later boxes.


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## ALKYGTO (Mar 29, 2010)

Another consideration is the input shafts spline count. M-20 and m-21 have a 10 spline input shafts and the m-22 has a stronger 26 spline input shaft. Output shaft is also stronger.

OP still has not divulged his combination....389? 400? 455 ? Stroker? :lurk:


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## 1965goat (Sep 8, 2014)

I definitely wanna keep my rear end and stick with a 4 speed. I'm now thinkin:
2.164
1.620
1.200
1.00

These seem to be better. If you want a link to my options, tell me and i post a link


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## 1965goat (Sep 8, 2014)

And I'm building my engine as a 416 stroker with an 871 roots supercharger with a effective cr of 11.75:1


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## 1965goat (Sep 8, 2014)

And I know. Supercharger combo I should have an automatic. Got it covered. I found a 4 speed capable of extreme hp. It has a 32 spline shaft and has the external shift linkage so I can hurst shift it.


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## ALKYGTO (Mar 29, 2010)

With that much power you really don't need such a steep gear. I recommend 3:23's. You may run out of rpm on the big end.


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## 1965goat (Sep 8, 2014)

So what would the 4 gear ratios be?


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## Chris-Austria (Dec 23, 2010)

No matter how you choose the gears, I don't think you will like a 1:1 4th with the 4.11 rear.


Here some calculations that might be interesting:

26" tires, 1:1 4th gear, 4.11 rear = 3500rpm for 65mph and 112mph at 6000rpm
26" tires, 1:1 4th gear, 3.23 rear = 2750rpm for 65mph and 144mph at 6000rpm
26" tires, 0.65 5th gear, 4.11 rear = 2250rpm for 65mph and 173mph at 6000rpm


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## 666bbl (Apr 13, 2014)

ALKYGTO said:


> With that much power you really don't need such a steep gear. I recommend 3:23's. You may run out of rpm on the big end.


And those RPM will come up really fast! Uh (cough-cough) shift light...:exclamation::exclamation:


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## geeteeohguy (Feb 2, 2008)

I've driven GTO's with 3.90, 4.11, and 4.56 gears. In every case, you were in top gear driving in town, usually by 35 or 40 mph. Great for 1/8 mile or 1/4 mile racing, but utterly worthless to use the car as a car. I changed the 3.55 gears in my '65 GTO out for 3.36 gears, just to make the car more livable. I think with a blower on a light car with a 4 speed stick, a 3.08 or 3.23 would be optimum. You _still_ will have a hard time controlling the car.


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## 1965goat (Sep 8, 2014)

Ok so how about either a tremec tko600 5 speed with an awesome overdrive, or get an overdrive kit for a Gforce gf4a 4 speed


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## ALKYGTO (Mar 29, 2010)

I use the Tremec TKO in my car. .082 overdrive with 4:11's and I can cruise at 75 mph at around 2500 rpm. Perfect. Car is 3700 lbs with me in it and 1/2 tank of fuel with a 12.5 inch ET Street tire and I haven't hurt it yet. Engine put out over 750 rwhp 6 years ago when I first installed it and is probably in the 900+ range now.


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## 1965goat (Sep 8, 2014)

Ok I think I'm definetley goin with the tko600. Seems like it'll be the perfect trans unless I got the gf4a and got a clutchless overdrive function for it, but the 5 speed seems more cost efficient


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