I've got a 4L60E in my car, and I've got a few things done to it, here and there. A few of those things include the LT4 hot cam package. The rollerrockers, valvesprings, and obviously the cam. I stepped from a 3.23 to a 3.42. Now I'm thinking maybe I should have gone with the 3.73s.

Would 3.73s be streetable? How badly would gas mileage suffer? Is the swap even worth the extra money? How much of a gain could I expect in the quarter? How badly will they hurt my trapspeed (I'd rather have a high trap than a low 1/4 ) I'm not worried about getting to the end of the track in less time as much as I am about getting to the end of the track at a higher mph. For me, it's how fast I'm going that's the rush......not trapping the highest 1/4.

 

The 3.73's made a real difference over the 3.42's I had before(Originally had 2.73).All the gears are crisper and the car just feel s like it really wants to go and accelerate like hell. I don't race and my mods are mild and I do a lot of highway driving so I got the BF Goodrich 265/50/16 tires which are an inch taller than stock and give me 5mph more per given rpm. Also with 3.73's the vibrations from the driveshaft at 90+ were annoying. I got an aluminum one from a 98 on EBay for 150.00 and that cleared things up nicely. My gas mileage is currently 12-14 MPG but I have a lead foot. Tuning up with new plugs and MSD and O2 sensors(Car scans rich and coughs up carbon on the garage floor on startup and has 91,000 miles) so mileage should increase soon.

 

If you have the extra money then go for it. 3.73s make the car real quick off the line. Somewhere on f-body.org there is a gear caculator that can answer some of your questions. The 3.73s do not really affect streetability. I would go for it.

 

i went from 342 to 373 and i love them.

 

A4s and M6s are totally different though.

 

Thanks for the info! I visited www.thunderracing.com, I believe, and that's who had the gears. They had two seperates to choose from. They had Motive, which were $195 for either 3.42s or 3.73s, and then they were also selling Strange. Those gears were priced at $225 for either 3.42s or 3.73s.

Any suggestion as to which brand I should choose?

 

Motive whine less.

 

always had good luck and never heard anything bad about Motive gears. They lasted in my 4000Lb '76 Skylark with 300HP and DAILY street beatings just fine (went through 3 trannys though )