Rear gear ratio choice?????

[chevy4life]

Hey guys, I'm putting a 4l80e into my 72 chevelle mating to a 5.3 truck engine. It will be putting down roughly 450hp. I want the car to take off quick but be enjoyable on the highway. I'm running 25in tall tires. Stuck between 3:55 or 3:73... Any help?
Thanks, Anthony

[Schwartz Performance]

With that small of a tire id do the 3.55.

-Dale

[chevy4life]

dale, thank you very much!

[1989GTA]

I agree. Go with the 3.55 ratio.

[Sean Cooke]

I have a 4l80e - 3.73 cruises nicely - I drive a lot!

[BonzoHansen]

25" rear tire? that seems short on that car. that is like a 215/60/15 in height. what size are you running?

[chevy4life]

sorry its a 26inch. theyre 295/35r18's in the back. but i have a somewhat urgent question. i have the opertunity to pick up a really nice 12 bolt all set to drop in with an eaton posi but has 4:11 gears. any comments? im really tempted the guy is asking 1400. later on swap out the gears. like i said im running a 4l80e

[TheJDMan]

The 4:11 will be fun around town but unless you have a double overdrive IMO it will be miserable on the hiway.

[67rally]

sorry its a 26inch. theyre 295/35r18's in the back. but i have a somewhat urgent question. i have the opertunity to pick up a really nice 12 bolt all set to drop in with an eaton posi but has 4:11 gears. any comments? im really tempted the guy is asking 1400. later on swap out the gears. like i said im running a 4l80e

If that were for a Camaro, I'd be all over it. 4.11's with my 6 speed would be perfect.

[chevy4life]

just found out it was rebuilt 10 years ago and never even put in a car... im going to get it friday. if i hate the gears in the spring then ill just swap them.

[67rally]

just found out it was rebuilt 10 years ago and never even put in a car... im going to get it friday. if i hate the gears in the spring then ill just swap them.

Are you going to swap them out yourself? If not, you might be close to the cost of a brand new rear end by the time you're done.

[chevy4life]

No I won't, I have a close family friend who does them tho. The guy wants 1200 bucks for it. I debated on going brand new but can't justify spending 3 thousand right now

[armourmark]

You will enjoy the gears. I have a 4l80e with 3.90s and love em.

[andrewb70]

With a 5.3L, I would run a 3.73 gear.

Andrew

[V8VW]

What about a 4:11 with 700R4?

[Bygblok]

I run a 3.31 with my 700r4 and have 285/35/r17's.With the converter locked it turns around 2400@80mph. I'd like a little more gear but to be honest it's happy with the 3.31's so why worry with it until I change the whole rearend. If you highway drive it much I'd surely go to the 3.55

[Kenova]

What about a 4:11 with 700R4?

Keep in mind that a 700R4 has a rather steep 3.06:1 first gear ratio. Running 4.11s with the 700R4 would give you the same overall gear ratio of a TH350 running 4.95s in the rear (if my math is correct).

Ken

[V8VW]

The reason I ask is, I have a narrowed 9" in mt 2" x 3" tube chassis, VW Squareback station wagon project car. The gear assembly is a new, never installed, 4:11 with my 700R4 and sbc 350/330 crate motor. Really hate to have to buy a new set of gears if i can avoid it.

[Bygblok]

The reason I ask is, I have a narrowed 9" in mt 2" x 3" tube chassis, VW Squareback station wagon project car. The gear assembly is a new, never installed, 4:11 with my 700R4 and sbc 350/330 crate motor. Really hate to have to buy a new set of gears if i can avoid it.

1st gear will be virtually useless with that much rearend gear in it unless the tire height in HUGE!!

[carguykeith]

With the converter locked up you should be fine with 4.11s, that's the same as 3.08 and 1:1 which I ran for years and never had a problem with on the highway. Another option instead of changing out gears would be to go with a 285/40 tires if you need a little lower cruising rpm.