I got 3.73s on accident?

[The Unknown 7]

So i bought a rear end from some dude off craigslist. he told me he pulled it off a 97 z28 and it had posi and 3.42s. I take it to the shop to have it put on, the guy said he counted the teeth and splines and it added up to 3.73s... But im not sure Im feeling it, cause from what I heard my rpms would be a lot higher as well as my speedo would be more off. right now at 60(by the speedometer, which I havent fixed yet) I go about 2000rpm and I put it on the dyno at my job to see about the speedo, at 40 its off by 5, 60 its off by 10, and so on. Anybody got any input?

[Fondle]

Re: I got 3.73s on accident?

is your car auto or manual?

so is it at 2000 when your actually going 60, or 70?

[venom3300]

Re: I got 3.73s on accident?

i have 3.42s and i run about 2k rpms at 60 if that helps

[checkbit]

Re: I got 3.73s on accident?

you could send me the ring gear and pinion :D i don't care which it is, 3.42 or 3.73, it's better than my current 3.08 - at 60mph i turn exactly 2k rpms (auto trans)

[The Unknown 7]

Re: I got 3.73s on accident?

Yeah its an auto, and i'd actually be going 50 cause the speedo is off

[ssms5411]

Re: I got 3.73s on accident?

We need what size tires you are running to calcualate what gears you have?

[cam98aro]

Re: I got 3.73s on accident?

put the back end on jack stands, and make a chalk mark on the drive shaft, spin the back tires 10 times, and count how many times the driveshaft turns, then divide it by 10 its a quick and easy way to find what your ratio is

[The Unknown 7]

Re: I got 3.73s on accident?

put the back end on jack stands, and make a chalk mark on the drive shaft, spin the back tires 10 times, and count how many times the driveshaft turns, then divide it by 10 its a quick and easy way to find what your ratio is

Alright man I'm gonna do that later today.
Also, I have 255/40/17s in the front and 275/40/18s in the rear. Its an auto too. Also when you guys are cruising at about 60, are y'all at 2k rpms, in third gear, or 4th. Cuz untill I lay off the gas and let it down shift its at 3k, put 4th its at 2k.

[bwkmaro]

Re: I got 3.73s on accident?

thats wierd im a 1800 rpms in my car at 60 and have 3.42s with a auto i might have to take a second look at my rear end

[whitdog54]

Re: I got 3.73s on accident?

thats wierd im a 1800 rpms in my car at 60 and have 3.42s with a auto i might have to take a second look at my rear end

I have 3.42s/A4 and at 60 im right around 2k rpms.

[BallerMaro13]

Re: I got 3.73s on accident?

thats wierd im a 1800 rpms in my car at 60 and have 3.42s with a auto i might have to take a second look at my rear end

sounds like you might have 3.08's

[bwkmaro]

Re: I got 3.73s on accident?

thats sexy, make a nice up grade to 3.73s then. oh i just thought of something i dont think stock z28 came with 3.73s unless it was special order cause all the v8s were rather low gearing like 3.08 and less becuase of the 6speed t56 i might be wrong but it does make sense... i had 2 friends trade out there stock gears in the v8s and they were both like a 2.48(or something close to that)

[BallerMaro13]

Re: I got 3.73s on accident?

you can pull the rear off an ls1 fbody and usually find 3.42's with lsd

[ssms5411]

Re: I got 3.73s on accident?

you can pull the rear off an ls1 fbody and usually find 3.42's with lsd

X2 here they go for $300-$400 for 3.42 posi with decent miles.

[bigbrian442]

Re: I got 3.73s on accident?

thats sexy, make a nice up grade to 3.73s then. oh i just thought of something i dont think stock z28 came with 3.73s unless it was special order cause all the v8s were rather low gearing like 3.08 and less becuase of the 6speed t56 i might be wrong but it does make sense... i had 2 friends trade out there stock gears in the v8s and they were both like a 2.48(or something close to that)

95 and later V8 6 speed cars only came with 3.42's. Auto V8's could get 2.73's or 3.23's.