LS swap. Whats a good street gear ratio.Pics inside with detail.

[Nasty-LSX]

I am still waiting for a large amount of parts to come in before I start pulling the truck apart.
(old lesson learned) never take anything apart till you have everything you need to replace it lol.

I will be starting a build thread in the forums as soon as everything is in. For now I would like to
get a posi put in. I will be using a
Detroit TrueTrac . The engine is a 2015 6.0 with a
4l70e from GM PERFORMANCE. these are the gearing specs from first to fourth.. 3.06, 2nd: 1.62, 3rd: 1.00, 4th: 0.70 I want to be able to do 70 MPH at 2000 rpm.
Any ideas? thanks

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[bucket]

What's your rear tire size?

 

[Derrick]

I found a calculator for this all you need to do is play with ring and pinion ratio (rear gear)
http://spicerparts.com/calculators/transmission-ratio-rpm-calculator

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I just assumed you are running 32s if incorrect put in your tire size in. I think 3.73 will work for you. even with 31s you just hit 70 mph with 2k rpm

 

[bucket]

Tires in pic look to be 275/60/15. Without looking it up, I think those are in the 27-28" range.

 

[Derrick]

those are small tires. lol 3.73 gears will not work then.

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[DoubleDingo]

I was going to say 3.54 if you can find them. 70 with a 32 inch tire is about 2600 in 3rd, add-in OD and you'd be about right. Smaller tire, may still be okay if not better.

 

[Nasty-LSX]

What's your rear tire size?

335 30 18

 

[Nasty-LSX]

I think 3.42 would be a good gear for rear. it also has a 2800 FTI stall. TURBO coming soon.

 

[Rusty Nail]

3.23 for teh win.

I had an '81 Trans Am with a Pontiac 406 in it and the 3.23 disc brake posi ...that mother f would FLY!

 

[Rusty Nail]

I am still waiting for a large amount of parts to come in before I start pulling the truck apart.
(old lesson learned) never take anything apart till you have everything you need to replace it lol.

I will be starting a build thread in the forums as soon as everything is in. For now I would like to
get a posi put in. I will be using a
Detroit TrueTrac . The engine is a 2015 6.0 with a
4l70e from GM PERFORMANCE. these are the gearing specs from first to fourth.. 3.06, 2nd: 1.62, 3rd: 1.00, 4th: 0.70 I want to be able to do 70 MPH at 2000 rpm.
Any ideas? thanks

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Those wheels KICK.ASS!

 

[bucket]

335 30 18

Well that's certainly not what's in the picture, lol. Got a picture of the new ones?

 

[Rusty Nail]

LoL!

/facepalm.

/smh...

I lost interest.

 

[Derrick]

I would still recommend 3.08 rear still you will hit 70 mph at 2k rpm with 25s.

 

[4WDKC]

323, is only 95 more rpm than 308, personally i think the tires will look to short on the truck.

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[Nasty-LSX]

323, is only 95 more rpm than 308, personally i think the tires will look to short on the truck.

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Im thinking your right. I may go next size up. I have not bought them yet. Wheels will be 18/12.5 rear and 18/10 up front from CCW. CLASSSIC wheels with 4/6 drop