View Full Version : Using 3.90 gears?


RW99
03-23-2005, 02:18 PM
Anyone using 3.90 in their Strange 12-bolt? Comments?

I'm considering the change from my stock 3.42's in my 10 bolt to something quicker in the new rear end. Not sure if I want to go all the way to 4.10's.

Thanks..

TPY2KWS6
03-23-2005, 02:29 PM
I'm wondering the same thing. 4.10 is to much for my planned setup and 3.73 is a little to low. 3.90 is perfect though. There is some concern about noise but I'd like to hear from somebody that has them to see just how bad the noise really is.

wrencher
03-23-2005, 11:01 PM
I will let you know, but I have been waiting for 7 weeks now for my rear from strange........nice

Ragtop 99
03-24-2005, 08:15 AM
I think 3.90s would be a good choice, depending upon your driving habits. The 3.73s are left over from my A4 days and are a bit taller than I like. 3.90s are a great all-around gear. With 3.90s, highway revs at 75 mph are still pretty low and the lower gears are similar to the effective ratios used in the Z06 vette. 4th gear will pull decently in town w/o downshifting. If you don't do much highway driving, I'd look at 4.10s as the short first gear is great for a lot of stop & go traffic and 4th will be very responsive although you may need to use 5th gear more.

For best track ET, 4.10s are a good choice with your cam.

Kurtomac
03-24-2005, 08:24 AM
i have 390s in my moser......not any louder than the day i had them put in 300passes on slicks later, i launched them at 6500 sunday cut a 1.64 60ft with it and drove it to work last night....couldnt ask for a better all around gear, although im swapping out for a 410 or 430 for a better 60ft, 76mph is 2000rpm in 6th, FWIW i dont think ive ever heard a quiet 12 bolt.....dont hesitate on the 390s due to the noise issue, youll be happy with them if you dont want to go all the way to 410s.....whatever you do dont do 373s youll kick yourself wishing you went more gear later on
http://slackercracker.com/hpt/upload/411vids/buckvskurt.mpg
theres a vid im left lane with my 390s right lane has 373s both 12 bolts both of us HC you can see the diff it makes out of the hole
hope i helped
kurt

1ScrudeDude
03-24-2005, 12:03 PM
Yeah no shit, once at the strip, no such thing as a quiet 12 bolt.

Fuckin go for it...

Josh
03-24-2005, 07:13 PM
I should be able to finish up the installation of my Moser 12-bolt with 3.90s tomorrow, so I'll let you know how they feel compared to the 3.42s. :)

Josh

LS1Adam
03-25-2005, 03:42 PM
I should be able to finish up the installation of my Moser 12-bolt with 3.90s tomorrow, so I'll let you know how they feel compared to the 3.42s. :)

Josh

well!?!? how about you speed up that install huh!! j/k. the anticipation to hear word on the 12 bolt w/ 3.90s sucks! its really getting to me now!

RW99
03-26-2005, 08:38 PM
... and are we all on the same page as far as preferring Strange over Moser, given Moser's recent problems?

wrencher
03-28-2005, 09:35 PM
Be prepaired to wait for strange though, they are as of now out of 3 series posi's & will have to wait 2 weeks at least for them to come in. I now have to go w/ a 4.10 or wait for 9-10 weeks total for mine to be completed........ real nice

Josh
03-28-2005, 10:29 PM
Sorry guys, I meant to post shortly after getting a few miles under my belt but then I put it off and forgot. Anyway, I like the 3.90s. It's not as drastic a change as I was expecting, but it's still noticeably more peppy than it was with 3.42s. I find I'm usually one gear higher at a given speed than I was with the 3.42s.

If I had to do it over again, I'd still go with the 3.90s, but only because I spray the car. If I were strictly NA, I'd probably step up to 4.10s, though I doubt there could be that much a difference (after all, people say the switch from 3.42s to 3.73s is virtually unnoticeable).

The rear does whine a bit on acceleration. It isn't unbearable, but it is noticeable. That said, it can't be heard over the exhaust when under load nor over the stereo when moderately turned up. I was fully expecting some noise, so I'm not too bothered by it.

So, in a nutshell, I'm pleased with the 3.90s. The car is more fun and easier to drive, especially with my big cam.

Josh

RW99
03-29-2005, 09:24 AM
Thanks for taking the time to update us...

TPY2KWS6
03-29-2005, 12:43 PM
Looks like I'll be going with the .90s :D

Justin99TA
03-30-2005, 11:56 AM
I have 3:90s in my moser 9inch with my auto and love it! Its not much worse then the 3:73s. Im going to the track on Sunday so I dunno know about any dif yet

Hawkcmc
03-30-2005, 12:44 PM
I am partial to Ford 9 inch's. Dont get me wrong prefer GM over Ford ANYDAY, but Ford 9"s can be done better and cheaper than any 12 bolt I know. I could probably get you a good ford 9" with 4.33's, detroit locker, and strange nodular case for $1800 within a week. and That thing is not going anywhere. 12 Bolts I just think have a long way to come in my opinion.

CMC

RW99
03-30-2005, 12:45 PM
...but on a 9 inch I can't keep my ABS, right?

Hawkcmc
03-30-2005, 01:51 PM
there are ways to keep it but none are widely sold yet. I am working on a way to keep mine so when I figure it out I will hopefully be able to pass on part numbers and places to get everything along with instructions.

CMC

z-ya
04-03-2005, 06:23 PM
there are ways to keep it but none are widely sold yet. I am working on a way to keep mine so when I figure it out I will hopefully be able to pass on part numbers and places to get everything along with instructions.

CMC
That would be very helpfull