hey i want to do gears, and there is a 4.11 ten bolt in the 4 sale sectoin for a good price, but would that be too much for a automatic lt1? is it possible to find out what rpm and in what gear it will cross the traps at? rite now it does about 103ish. and how bad will it effect my gas milage? i figure im better off with just buying another rear end so when this weak a** 10 bolt gives i have a spare, btw i run drag radials so i think traction will b ok

 

I drove a 4.10 a4 from NY to VA lol. Going 78 the entire time and tacking wayyy up there. It was about a year ago so i have no idea about exactly what rpm range. There are calculators though

 

I personally would say so, 4:11's are better suited for M6 IMO.

 

well gas milage isnt a huge deal because i drive the car mostly around town at lower speeds, and i try to stay under 65 on the high way when i am on it. at lower speeds gas milage shouldnt be effected right? because the transmition shifts at the same rpm so it will just be in a higher gear... mabe i should just search for a 3:73 rear tho, i dont wanna top out at 100 mph

 

with stock tires (245/50/16)...youll hit 112 in 3rd gear at 6 grand...in 4th at 65mph youll be tachin at ~2500

 

What would OD be?

 

I had them in my car for a year and my wife drove the car a lot on the freeway.
Never had a problem and with the hot cam the car ran great. It is a lot of gear for a auto but unless you like 130mph blasts I don't see them as a problem.

I like the gears much better than when I switched to a vigilante and 3.23's

 

I broke my 3.42s, and installed 4.10s w/an auburn pro series (A4), literally the first modifications to my 65K car. Was hyperteched at the same time since I had to adjust for the speedometer. Dropped from 14.30s@96 to 13.9/14.0@99 With my current mods, (shortys, ORY, CAI, 275/40/17 street tires, LT4 KM, 6100 shift) it runs 13.70s@101. I shoot through the traps at 6000-6100 in 3rd. Finally broke down and ordered a catback, and when I install it next week, I may find myself shifting into 4th in the traps.

Other observations. 4.10s made the hypertech shift improvment option mandatory. The stock shift was so slow that the gears dragged the car down on a gentle 1-2 shift. You'd get deceleration in the midst of acceleration. It's a weird description for a weird problem. My transmission is in perfect condition. With the shift firmness up, it REALLY goes into 2nd. Like dangerous for amateur drivers in the rain, you gotta be aware of the shift point when pulling out into traffic. 1/4 throttle can loop it. Part of that is the super tight posi. But it also changed the character of the car, and really makes it feel agressive. Sometimes good, sometimes not. I go to indy raceway park's street drags all the time. Last tuesday I raced 3 late model cobras (not blown) a total of 5 races, and won every time. Why?........4.10s baaaby. The cobras see stock muffler & tips and try to pick on me. 4.10s couldn't save me from a supercharged marauder though. Doh!

Highway manners suck. I have to go the speed limit, because it screams at 2800-2900 around 70-75. No longer feels like a 150 mph car, because it's not. Brief excursions into the 90s require 4000 rpm. It really ruined it for road trips, which I used to love to take it on. Cost me 2-3 mpg highway, probably 5 mpg city because it encourages harder driving. Noticably more vibration, noise, and rattles in the car from the higher driveline speed. Hope you like road trips with the stereo up, cause it goes WAAAAAAAAAAAHHHHHHHHH!

It doesn't burn out as well. It's easier to get them going, but I lack the power to brutalize them in 2nd. So the limited wheel speed available in first cut total burnout length by about 30%. With the wheel speed I had with 3.42s in 1st, once you got em going, people would ask- "Is that John Force?"

After 2 years, and about 15K miles of 4.10s, I'm seriously considering installing 3.73s this winter. They've been fun, but it's time to move on. It's a shame that 3.90s aren't available. 250 less rpm at 70 would make all the difference.

Hope this wasn't too long, but it's a love/hate relationship for me.

 

well i have a 93 so the computer dosnt controle the transmition, but it shifts pretty firm anyways probably because of age so that wont be a problem. i think im gonna probably go with like 3.73 or mabe 3.42. anythings gotta be better then 2.73s. well i run 13.8 now without the d/rs so im hopin for like 13.5-13.6 with them now, wow if the 4.10s droped ur et by 4 tenths i cant wait to see what gears will do for me

 

Since it's on a similar subject, would 3.42s be a noticable difference coming from 3.23s? Or would 3.73 be better to go for? I try to stay under 2000rpms on the roads around here. What would the rpms be at 65mph?

 

Not too much of a difference.
For RPMs measure at speed, http://www.f-body.org/gears/

 

I don't think I'd put 4.10's in an auto unless two things were going on 1) I really wasn't going to drive it on the highway (read: mainly a drag car), and 2) I had the valvetrain and tuning in place to raise the rev-limiter so I could wind the gears out more.

I personally loved the 3.23's I had. They went well with some moderately ported heads, HOTcam and bolt ons. Good highway manners, good top speed, good acceleration. I rode in a guys car with 3.73's from here to Atlanta, and it was annoying with the engine noise, shakes and vibrations.

 

4.10's for auto , 3.73's for manuals-DONE

 

Think ya got that one backward. 6sp is double overdrive.