Dominic Sorresso

I'm doing 3.73s but I have 3.45's w 19" Z06 wheels so looking to get back to an "effective" 3.45.

HAWAIIZR-1

I do a lot of city driving while in Hawaii and now in Japan so 4.10s were the ultimate for me and love em' as well as not going back to stock. As many said, it really depends on how you will drive the car.

mgg

Paul, changing the rear end ratio is a personal opinion deal. Jim Voter's suggestion of driving a car that is close to yours is the best way to find out if you like them or not. I have 373 ratio in my road race car and its very good gearing for the engine characteristics and most of the tracks I've run at. It is very difficult to have the perfect gear combo for racing without being able to fit the track but the 373s keep the motor in its power band and that is what is most important when racing. I replaced my gears in my ZR-1 with 410's and I love them. Thats just my opinion. My car is mildly modified with ported plemum & injector housings, headers, exhaust, haibeck prom etc. One thing that I agree on that others have suggested is that you better plan on keeping a relatively new set of decent tires on the car or first gear will be rendered useless with street pressures from a stop. New tires will hook pretty well but once they age you will find it difficult. For driving around town and cruising up to Jims from my house I find the 410's great. To be honest there are advantages for every gear set but you need the set to be one that YOU like, not someone else. My only opinion is that I would be not in favor of the 456's as to the fact without slicks or even drag radials you will blow the tires off in first gear. I bet it would be fun though. The best gear is the one that makes you happy in your car. Take Jims offer and drive a car with different gears and see what you think. I drove Jims car before I made the decision on mine. In my opinion it just makes the car a little more edgy and I like that. Overhead cam motors like gears! I always said that if I ever bought a ZR-1 , I would put 410s in it and I am glad I did.

DDSLT5

Depends on the power level. 4.10s for stock or mild mods, 3.90s for a 368 and 3.73s for a 415. 3.45s are silly for a ZR-1.

mike100

I ran into a guy who used to have a 94 that was modded a little and he said 3.73's were the single best thing he did to his car back when he had it.

zr1fred

4:10's are great for acceleration on the street with stock or slight mods, and cruising @75mph. Appox 2mpg less if it matters. Us old timers seem to remember the big gears in the 60's. The six speed changes all that.

XLR8TIN

4.10 works for me, close to red line in 4th in 1/4 mile & close to redline in 5th in 1 mile

8388

I love my 3:45's but when you make a ton of power nothing beats my 3:07's

Need4Speed90

i love my 4:10's but i had to get used to it, but my friends dad drove it and he said its something you have to get used to...id go with 3.73 for a good medium

93Polo

Power level and goals will determine the best gear. 4.10s for stock or mild mods and 1/4 mile times are your goal on some sticky tires.

I would not go that deep in any of the 6 speed cars I've owned, 3.73s or 3.90s for me. I don't care about 1/4 miles and want the gears to be a bit wider in the twisties. It is also nice cruising at lower rpm.

Paul Workman

For a 350 cid that sees a LOT of drag racing, maybe even the 4.30s might we worth considering. But, certainly the 3.45s are "a bit" small (prolly had to do with fuel economy and gas guzzler tax avoidance).

P.

rickyrj1

I have the exact same set up as Dom. I'm happy with it

DRM500RUBYZR-1

The ideal ratio of rear end vs. gear should be 100% particulalrly if you are a plumber.
Any less gear or ratio would only be acceptable if you are say, Aniston, Jolie, or someone like that.
Same holds true for belly gear ratio.
Always insist on enough gear.
I will not even discuss speedo gear ratios.
Hope this covers it.
Glad I could help!

Marty
1FUNZR1
NCRSZR1
p.s. 3.73's

Zrxmax

Had 4:33s and thought they were to deep even for a stock motor. Had 4:10s until they broke and really liked them. Since I like more of a cruise gear I will try the 3:90s next time. Just put a set of 3:07s in for the next Silver State in May.

George45

New to the forum I am, but found this really helpful to me. Just landed a 91 ZR1 with 11.5k on it. Bone stock as far as I can tell except for the new tires I put on right after delivery. Nitto G2s.. The stock gearing is indeed a bit high even for cruising at 65-70mph in 6th gear. Im just not sure the expense of going to 3.70s or 4.10s is justified for me. I don't mind shifting down a gear or two when passing, but the stockers do require a little more to get it rolling. So maybe next year I will reach another conclusion on the gearing.

zrc3john

A 91 with eleven thousand miles? Wow, nice find..Car is probably in great shape......Anything besides tires needed to be replaced? Was it purchased from private owner or dealership?

George45

I do need to change out the bushings and gears in the headlights. The cooling hoses all seem to be leak free but are a little hard. They changed all the fluids. There is a sometimes vaccum leak under the plenum. It seems to come and go. Not very bad as it takes more than a few seconds for the pump to come on again. Does not do it all the time.Also need to replace the diaphragms in the air pumps for the seats. Other than that it is very nice.
The car belonged to two previous owner/collectors. The 2nd owner drove it very little over the last twelve years. I understand he has a large collection of exotic cars.
I have always wanted one mainly due to the exotic engine they have. I doubt I will do very little to it to enhance the power or change the sound of the exhaust. It drives and feels like a brand new car. None of the shakes or rattles I read about in the forums.

FASTAZU

500hp and 3:73 and I love it.