3:15 Diff question?
Thread Starter
Burning Brakes
Joined: Mar 2003
Posts: 874
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From: Bonita CA
3:15 Diff question?
I have a spare differential carrier with 3:15 gears. My question is will this carrier allow for 3:73 and 3:90 gear sets? Also, if I paln to FI to 500+rwhp, should I keep the 3:15 gears? Thanks
Pro
Joined: Apr 2005
Posts: 591
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I have 3.73s, 2800 stall and a Procharger--Speaking from experience and 4500-6000 "kinda hard 
miles" You better build the tranny and get the diff/gears from DTE 
The power is GREAT, finding and replacing the weak links is not
On most streets the 3.73 is perfect. If you're running top end, you'll shut down way before they fly by
miles" You better build the tranny and get the diff/gears from DTE The power is GREAT, finding and replacing the weak links is not
On most streets the 3.73 is perfect. If you're running top end, you'll shut down way before they fly by
Racer
Joined: Feb 2005
Posts: 482
Likes: 1
From: Waveland MS
Originally Posted by DJMRTS
I have a spare differential carrier with 3:15 gears. My question is will this carrier allow for 3:73 and 3:90 gear sets? Also, if I paln to FI to 500+rwhp, should I keep the 3:15 gears? Thanks
Going FI would put you in a pretty tight window of gears that would perform well. I have 3.42's with a Procharger, and it is probably just about perfect. I am about to change out the rear tires because I have the Goodyear GS-D3 tires. They are nice for non-FI, but now they just break loose anytime you try to get on it in first and second (and on the edge of breaking loose in third). You really have to baby them through the gears, or else you're spinning.
My next choice will be a set of road racing/DR type tires...probably Nittos. From there, I will probably stop a bunch of the spinning, and I will be able to use a lot more power. However, if I were to go to a larger ratio, I am sure something would break if managed to hook all of the power. So, for stock driveline components, and FI, I wouldn't go past 3.42's. I would give the 3.15's a shot first, and then change them later. The 3.15's would definitely give you a better shot at installing a Maggie. The power down low would probably be wasted on the 3.42's or higher (ratio). I don't have the Maggie, but that would be my guess.
