4th gen 10 bolt w/4.11 and 4th gear auto

[Link85x]

Couldn't think of a good thread name. 2 questions though. I found and i'm soon gonna purchase this 94 trans am 10 bolt, disc, with aftermarket 4.11. I did see the guts of the rear and the shits brand new. $100 is what i gotta pay, the kid bought a Gm 12 bolt for $2300 and no longer needs this one. My question is will the 4.11 be bad or too mouch for my car/motor? If so, i'll swap out for something smaller like 3.42 or .73. This is a deal i can't pass up. I've been looking for a 4th gen rear and they all usually go for about $400+. 2nd question, is there a way to illiminate the od, so when 3rd is done in drive, it'll go straight to 4th instead of over revving? In OD, throttle has to be at 75% to get into 4th, correct?

[Mr. Luos]

You will be spinning the hell outta your motor on the highway. It won't be terrible, but you will lose mileage with it.

Gonna get her off the line nice though!!

[Rally Sport]

True, but man you will own alot of stangs with that.

[89IROC&RS]

well the thing is, the 700R4 has a really deep 3.06 first gear, so youll launch as hard as a six speed with 4.11 gears with lower, say a 3.8 rear gear, id swap down to 3.73 gears as the deepest with your setup.

as far as eliminating the overdrive, your fourth gear is an overdrive, so if you want a fourth gear, you want overdrive. so im confused by your question, are you saying you want to avoid the downshift from overdrive at full throttle??? there is a modification to limit the downshift to 75% throttle giving you a bit of extra pedal travel, but i think that the ability to run in fourth gear at full throttle is both a bad idea, and possibly not possible. something about lubrication or line pressures while in overdrive.

[SMOKINGIROC]

the 4.11 wouldn't be bad for the street but it would suck on the highway. i can't remember the site but they had this kickdown cable that let you put 90% instead of 75%, i'll look for the site but i think it cost a pretty penny though.

[Link85x]

Mr. Lous, that is what i wanted to hear!!! I will swap down when i get the chance though. 89, i was confusing myself when i wrote that post. Basically, i was wondering if there was a way to get into 4th at WOT. But that is a bad idea i guess. Would a b+m mega and shift kit would make it easier, right?

[Link85x]

89, or anyone else, i know you need the master cylinder and the porportional valve. My question is, can i buy these seperate? I won't be able to get them from this guy, he's leaving them on the car.

[Earlsfat]

[quote=89IROC&RS]... but i think that the ability to run in fourth gear at full throttle is both a bad idea, and possibly not possible. QUOTE]

I don't think I've ever heard anyone say "possibly not possible" lol, I like that one.

On a serious note... Are you talking that it's bad in general to run WOT in 4th, or just with an automatic trans?

[Mr. Luos]

You don't want to get into 4th at WOT. Just like I shouldn't be shifting into 5th or 6th WOT.

[Earlsfat]

4.11's suck without overdrive. Yeah they'll get you to the speed limit quick, but if you're running a 27.5" tire and a 1:1 final ration you're looking a 55-60 MPH MAX to kepp your RPM's in a reasonable range.

Richmond's website has a calculator that will tell you what to expect for RPM's if you know what year rear end gear is, tire diameter, and final drive ratio.

Put it this way, I have a 10 boilt with a 4.11 and 1:1 4th gear. To get the highway speeds I want, I need a .64 overdrive and it's gona cost me a minimum of $1500 for a new tranny.

[Earlsfat]

Originally Posted by Mr. Luos

You don't want to get into 4th at WOT. Just like I shouldn't be shifting into 5th or 6th WOT.

lol. Damage the trans???

Are you talking, shift and then hit wide open throttle after in gear or shift and kind of dump the clutch at wide open throttle?

Confused.

[Mr. Luos]

Originally Posted by Earlsfat

lol. Damage the trans???

Are you talking, shift and then hit wide open throttle after in gear or shift and kind of dump the clutch at wide open throttle?

Confused.

Powershifting, going full throttle in gear, etc...

Anything less than 1:1 can run the risk of damaging the tranny.

It is safer to go WOT after you are in gear, but still....it could do damage. More so on an older tranny.

[Earlsfat]

Soooo... what, you're done at 1:1??? or should be? I guess the drag cars have bullet proof transmissions???


That would mean that technically I'd be done at like 129-ish mph??? 27.5" rear tires, 4.11 rear gear, 6500 RPM and 1:1 final ratio. That sucks if I'm drag racing.

[Mr. Luos]

Should be is right.

Race cars are completely different though. They aren't designed for street duty. Much stronger tranny's.

[Savage Messiah]

do it.