I have a 1991 with a modified 355cid motor and a beefed up 700R4 transmisiion. I am currently looking for gears and was wondering if 3.73s are too much. I dont drag race and do little highway driving. I heard that 3.73s wont let the car shift into OD. I was curious as to who has a 350 with the 700R4 and 3.73s and if they experience any problems with this set up?

 

What do you have for a cam (rockers if there 1.6's) and tq. converter?
3.73's might be right for you.
Have you done any thing to your trans, valve body or computer to change the shift points?
You have to make a choice do I want to cross the 1/4 mile line in 3rd at WOT or in 4th.
3.73's I think you might run out of rpm's and have to go into 4th befor the 1/4 mile line.
It depends where your power band is.
I would go with 3.42's.
What do you have now?

 

I'm currently doing this swap, as soon as my engine is reassembled. It won't keep the trans from shifting into Overdrive, it'll probably shift at a lower vehicle speed tho. To get the most out of 3.73's or higher, some modds should be done to the governer to re-dial in the shift points to optimum.
I Drag Race and don't drive the Interstate very often(..at least not in this car..)so these gears will put me in a higher rpm powerband that will match my cam/head package.

As for you I would suggest 3.42's, these will give good acceleration and cruising rpm's. But if you already have 3.23's I don't believe the difference in performance would be worth the cost.

 

The motors specs are--> 355cid, Accell 58mm throttlebody,Edelbrock runners and baseplate,24lbs Accell injectors, Crane 1.6 gold roller rockers, Edelbrock Performer 64cc(2.02"/1.60"), Comp Cams hydraulic roller cam, Comp Cams hydraulic roller lifters, Federal Mogel hyperutectic full floating pistons, Moly seal pro rings, Eagle H-beam rods, stock ground/polished/balanced crank, Cloyes dual roller chain, Corvette hi pressure oil pump, MSD distributor/coil/6AL, etc. Hypertech Thermomaster chip, rebuilt corvette 700R4 with modified valve body, Transgo shift kit, 2600 stall converter etc. Next to go in is a Holley AFPR then gears. I dont like my 3.23s and the cam specs I cant remeber right now but it said it requires 3.55 gears minimum. Which gears do you think would work?

 

You just aren't going to notice much difference going from 3.23s to 3.42s. And the cost is not insignificant.

If you already have a 2600 rpm converter, I think you are probably as fast as you are going to get in the quarter mile.

Street light to street light is a different matter, of course.

It looks like your engine can turn 6000 rpm with ease. So like the other guy said, maybe have your tranny's governor reprogrammed to shift at 6200 rpm and then 3.73s might be workable.

For maximum performance in the quarter mile, a 700r4 is NOT a good choice. It is that oddball choice of second gear at 1.63 to 1. If it had been 1.8 or so you wouldn't have to over rev the engine to get it into the sweet spot, torque-wise, for the 1 - 2 shift.

A Turbo 350 is better for the quarter.

But you don't go to the drags and you don't go out of town, so that's my best advice.