Tell me what you have experienced with changing 3.42 gears to either 4.10 & 4.56. I'd like lower off the line times and the ability to use 5th and 6th gear in my M6.
I spoke with Don Stelhorn at SLP. He tells me that I do not need the paddle kit since I have the Auburn rear. SLP lost its supplier for gears, so I have to get them elsewhere. What are your thoughts on Jeg's & Richmond's?
Also, what solutions do you have for the sppedometer, either for the 4.10's or the 4.56's.
I want to keep the external appearance of the original Auburn rear for show purposes. Thanks.

 

madmanmike,

I think you will like the 4:10, I had them in my '94.
With anything bigger you will have to shift into 5th
in the 1/4. I would go with motive or strange gears.
I broke a Richmond gear in my '94, while I was still on
street tires.

Speedo calibration there are several options. They have
stand alone calibrators, Hypertech, custom PCM or
you could live with it. With a 4:10 the speedo will
be off 20%, so speedo reading 100 you would be going
80.

Hope this helps

 

He pretty much hit the nail on the head. Motive/Strange = good gears, go w/ them. I wouldn't go higher then 4.10's on a street car though IMO. And yeah, if you do buy a stand-alone programmer get the Predator, a lot more stuff you can do with it then the HPP3. Any performance shop around your area w/ LS1Edit outta reprogram your speedo for around $100 otherwise.

 

go with 3.73......dont get crazy

 

The guys at "Thunder Racing" say 4.10's are the way to go with the M6 for street/strip duty. I personally thing having to shift to 5th to get through the traps would suck(4.56's)

 

I think w/ 4.10s, if you don't bump up the rev-limiter a little or put a bigger tire on, you might tap the rev-limiter through the traps (maybe sooner)...again, I'm not 100% sure.

Also, w/ 4.10s or higher (numerically), 1st gear is gonna go real quick so I would recommend an aftermarket tach (AutoMeter is nice) or at least a shift lite...because the factory tach will NOT keep up.

 

Yes it would suck, and it would show on your ET. 5th gear is a mild overdrive gear.

 

Although you seem like you are looking for the best 1/4 mile performance I think 4.10s are the best for our cars. THe reason I say this is because I have heard MANY stories about the trannies not being able to last when shifting hard into 5th. Not to mention you would be shifting out of first so fast it might even cost you time on your 60'. I run a richmond gear in my '93 (it does have a 12 bolt) and I have had 3 full seasons of 5000 rpm dumps on ET streets with 3.55 gears. They are noisy though. If I were to do it again I would choose a strange gear. Go with the best gear out there, the extra price on something for your rear is worth it because you will have to replace it a lot less times

 

Thank you very much for your advice. Looks like the Predator programmer along with the Strange gears (4.10) would be the best option for me. I don't mind putting the extra $ into the car. As I said before, I want to keep it looking as stock as possible for show purposes.
As you probably know, to enter a car in a show as stock, you are only allowed to have two or three modifications. If you enter as modified, you are up against blowers with all chrome open engines.

 

4:10's are a little too much in my opinion. Your top speed with be decreased to under 120. But if 1/4 mile is what your after you should be able to do a low low 12 second before the rpms max out. I like the option to have top end and 1/4 mile times. Not saying much because I have 2:73's, but 3:42's are what I will be going for with the A4 soon. Has to be a balance of both for me.

 

I'm not sure about the 120 top. I heard of someone who has a car just like mine who hit 130 entering 5th. even if it does limit me to 120 in 6th, I don't really care about total top end. Handcuffs, car impounded, loss of business. Under triple digits you have a chance of avoiding prosecution. Now if I lived in Montana???????

 

I dont know where you heard this, but its not true

You should top out around 155 or so. HOWEVER, the driveshaft shoudl be upgraded if you do that. they say the DS critical speed is reached before that speed with 4.10s.

4.10s are a good choice, but with the weak rear, they like to spew teeth occasionaly. Thats why I went with 3.73's when I had the stock rear. Just be aware that the gears get weaker the deeper they get.

 

and gas mileage will suck with 4.10s........

 

i would go with 4.10 as the highest. u would shift too much with the 4.56's and that would be hell on the 10 bolt rear with a 6 speed.

 

not really. at most i lost 20-30 miles to the tank with 4.10s, love em i cant even imagine 4.56s too much gear for the street