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Which one should I go for to cruise around in.:confused0006:I have a mild 454 with a T350, I think my stall is 2000. My rear tires are 225-60-16. What are your opinions?
 

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Which one should I go for to cruise around in.:confused0006:I have a mild 454 with a T350, I think my stall is 2000. My rear tires are 225-60-16. What are your
I think it depends on the type of driving you do. If you are going be out on the interstate, the 3:08's would be a good choice.. just city driving the 3:42's might work out. At any rate this link is to a gear/speed calculator... just plug in the numbers to figure out what works for you..http://www.richmondgear.com/101032.html
 

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Rpm's will be 10% higher with the 3.36 compared to the 3.08. So if you're looking at 2500 rpm at a given speed with the 3.08, you'll be at 2750 with the 3.36. Backside of this is you have 10% more torque at the rear wheels with the 3.36 compared to the 3.08.

This deal is what make overdrive so great.
 

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Trifive Automotive Electrical Wiring Expert
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With a non-overdrive transmission, I would go with the 3:08 for cruiseing.
 

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Rpm's will be 10% higher with the 3.36 compared to the 3.08. So if you're looking at 2500 rpm at a given speed with the 3.08, you'll be at 2750 with the 3.36. Backside of this is you have 10% more torque at the rear wheels with the 3.36 compared to the 3.08.

This deal is what make overdrive so great.
This is why I am changing over to 3.08 gears in the near future. I just want to cruise my '57... I'm not out there to race her. :rolleyes:
 

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This is why I am changing over to 3.08 gears in the near future. I just want to cruise my '57... I'm not out there to race her. :rolleyes:

Just a fact here. 3.31 was the standard gear ratio installed in early '70s El Caminos with V8 engines from the factory. Maybe Chevelles/Monte's too? Not sure on those. Absolutely positive on the Caminos. They only had 1:1 final ratio transmissions (M22*/T400*) back then. No overdrives. 3.31 is a fine ratio for overall driving.
__
* on my '71 SS454
 

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Just a fact here. 3.31 was the standard gear ratio installed in early '70s El Caminos with V8 engines from the factory. Maybe Chevelles/Monte's too? Not sure on those. Absolutely positive on the Caminos. They only had 1:1 final ratio transmissions (M22/T400) back then. No overdrives. 3.31 is a fine ratio for overall driving.
Well at the present moment. I am running 3.55 gears with a 350/350. I am taching 3100 RPMs @ 60 MPH :eek: on the HWY. I am running 225/70R15 tires.
 

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Trifive Automotive Electrical Wiring Expert
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Just a fact here. 3.31 was the standard gear ratio installed in early '70s El Caminos with V8 engines from the factory. Maybe Chevelles/Monte's too? Not sure on those. Absolutely positive on the Caminos. They only had 1:1 final ratio transmissions (M22/T400) back then. No overdrives. 3.31 is a fine ratio for overall driving.
But in the 70's you needed all the torque you could get, to get the pollution controlled, detuned slug to move under it's own power. :)
 

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I have a 454 with 700r4 trans and 3.08 gear with 275/60 15

Today I was driving at 60 mph and only showing 1800 rpm.

With a big block don't worry about the 3.08 around town you will still have plenty of power to easily smoke the tires if you want.

Otis:)
 

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My 67 Nova came with a 3.36 gear. To me a good choice without overdrive. And not too bad with it.

57 Chevys with automatics had the same gear.

Depends on what you want. Performance/economy/engine noise are the things you consider.

There is no pat answer here.
 

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I run 308 in my 55, but with that eng probably 3:36. Esp if you have cam.
How do you get the overall diameter
eg rim size plus tyre
but what height is a 35 size, 45 series etc...
 

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Which one should I go for to cruise around in.:confused0006:I have a mild 454 with a T350, I think my stall is 2000. My rear tires are 225-60-16. What are your opinions?
At 3000rpm:
3.08= 77mph

3.36= 70mph.

I calculate tyre size at 26.6" diameter. approx.
 

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But in the 70's you needed all the torque you could get, to get the pollution controlled, detuned slug to move under it's own power. :)


Are you kidding???? Both my '70 and '71 are factory SS454 cars. The '70 was order with the 4.11. But the '71 has 3.31 which was standard and there was no lower ratio (numerically higher) option that year. You must be thinking of MID '70 years when the BBC was no longer an option. Also, as a point of referent I once had a '72 4-spd with a 350/270 hp engine and it too had the standard ratio and wa a fine driver city/highway. Keep in mind the original poster has a mildly upgraded 454, not some wimpy mid/late '70s 145 hp 350 or 305. Even with a mid-late 454 rated a a few hundred hp from a Surburban (aka - detuned slug) would have nearly 500 ft-lb of torque.
 

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Discussion Starter #17
I have a 454 with 700r4 trans and 3.08 gear with 275/60 15

Today I was driving at 60 mph and only showing 1800 rpm.

With a big block don't worry about the 3.08 around town you will still have plenty of power to easily smoke the tires if you want.

Otis:)
That's what I thought with a BB.
 

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Discussion Starter #18
But in the 70's you needed all the torque you could get, to get the pollution controlled, detuned slug to move under it's own power. :)
I'll have to say I never heard of it called a "detuned slug" so I was LMAO for awhile when I read that....Thanks I needed that.:D

I'm going with a 3:08 and ordering it from Ron's one of our sponsors. Thanks GKK:tu
 

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In most of the 70s we had an early tree hugger law called 55 mph and 3.36 would be about right for that speed. The problem is we have now growm used to the ODs are in all daily drivers. For example I got my old 74 Z28 out last weekend and went on a 50 mile road trip. I thought is was screaming at 70mph with 3.42s, 255/60/15s and a super T-10.
 
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