Gears

xXAzureMach1Xx

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Alright, Got a full eaton swap and T56 in my mach 1. I have stock 3.55 gears. I picked up a set of track wheels and found a GREAT deal on some new 275/60/15 MT. I know its a 28" tire and its goin to kill my gear. Im rebuilding the rearend and plan to run 3.73 with a 26'' tire, now with a 28'' tire im thinkin about 4.10s? The 4.10 should be about the same as 3.73 and 26'' tire. Is that about right? And how bad will the car be on the 315's dr on the street?
 

04Mach1Blurr

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On a 15 its going to rotate more than a 17in would. Correcting your speedometer is defintaley necessary. I still have the stock 5spd with 4.10s in my IRS. but lots of people run the 6spds with 4.10s when leaving the blower stock. usually when you hit 500+ you want to run lower like a 3.73 because traction is harder. For instance, my 17 nt555s 255s i could spin clean through 2nd gear and only at 425 to the tire with 4.10s, and thats punching it at 2k rpm and it breaking loose.

I think if you run a 15 on the street, its gonna be a higher than 17in rpm.
 
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xXAzureMach1Xx

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On a 15 its going to rotate more than a 17in would. Correcting your speedometer is defintaley necessary. I still have the stock 5spd with 4.10s in my IRS. but lots of people run the 6spds with 4.10s when leaving the blower stock. usually when you hit 500+ you want to run lower like a 3.73 because traction is harder. For instance, my 17 nt555s 255s i could spin clean through 2nd gear and only at 425 to the tire with 4.10s, and thats punching it at 2k rpm and it breaking loose.

I think if you run a 15 on the street, its gonna be a higher than 17in rpm.

If both tires are 28 or 26 then it doesnt matter what size the rim is. I know ill have to do something with the speedo, Not a big deal. The 4.10s with a 28'' tire should be like a 26'' tire with 3.73.
 

mach1owner

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the t56 is a 2.66 first is it? if so with a 28" tire a 4.10 would be a good gear since your blown.

Most guys without a blower that run a t56 will go 4.30 or bigger.
 

DarkMach1

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If the car is only for the drag strip then I would say get the 4.10s, I had 4.10s but since my car is a DD and all the runs I come across are on the highway I went back to 3.55s.
 

xXAzureMach1Xx

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Its not my DD even tho its my only ride. I have a work van. pretty much a weekend car and will start to see the track :banana:
 

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