Gaunt

iTrader: (11)

If there is one thing I've learned in my short existence so far, it is to get a second, third, and possibly fourth opinion on car parts.

My car will be setup to make very close to 850 rwhp. It will be an auto (4L80E), 408 cubic inch, F1A procharger setup.

This car will likely say WAY more street duty than track duty, but some track passes aren't out of the question. As such, this is my weekend warrior, not my dedicated track monster.

I need a rear end that will take this horsepower, and still be livable.

After talking to three vendors, the best I have come up with so far is this:

9 inch, of some sort (Currently between an M9, and MWC Fab 9)
Wavetrac
Torque arm provision
Backbrace
Powder coating, etc.

What do my LS1tech brothers think of this? I've tried searching a lot, and it keeps looking like MWC edging out the M9 by a little bit. Do I NEED a 9 inch for this kind of power/street usage, or are less expensive options available? I know it takes money to play if I'm putting down serious power, but if something like an S60 or similar is a viable option, I'm open to hear it. So far, my only experience is a local guy making 850-900 hp turboed and on a Moser 12 bolt.

Bob@BruteSpeed

iTrader: (16)

I'd say go either M9 or MWC Fab 9, don't do a 12 bolt. Bob

Gaunt

iTrader: (11)

Thanks Bob, I appreciate the honesty

I didn't think a 12 bolt would be the viable option, but I figured I would be 110% sure.

sixpack_2_go

iTrader: (1)

what spline axles are you going with?

penningta

iTrader: (3)

If you do a wave trac the only thing you can get is 35 spline I believe. I know they dont make it in a 31 spline. I have a MWC just picked it up this last weekend. Looks great but have know idea on how it will perform. I hope to be putting it in along with my Monster Stage 3 this weekend. I went with a spool though. I only put 1500 to 3000 miles a year on her and hope to see the track from time to time. I will see if I like it or not i guess. Have heard mixed reviews about a spool on the street.

NVR_SPDS

iTrader: (39)

Id personally go with the MWC Fab9. It has the strength to hold just about anything, and i believe it has more torque arm mounting options than the M9.

Like Bob said, dont even consider a 12 bolt, they just dont seem to handle the abuse nearly as well as a 9" or even an S60.

Bob@BruteSpeed

iTrader: (16)

http://shop.brutespeed.com/Moser-M9-...y-Complete.htm
Take a look at the torque arm options the Moser M9 has at this link. They designed just about every transmission crossmember you can think of. The M9 took all the abuse we dished at it in my Z28, shown below. Bob









http://www.powertvonline.com/video_detail.php?mId=2901 Video

cody161

iTrader: (18)

Go with a 9 inch of some sort, I can't say either the MWC 9" or M9 becuase I've just got the Moser 9" housing. Build it bullet proof so that will be one less thing to have to worry about.

Jawsgear

iTrader: (2)

^^ I agree with building it bullet proof out of the gate. If money is not the issue go with the best and do it once. I would do the 35 spline setup, wavetrac. M9 might be overkill for what you use the car for but it does look really cool under the car. Let me know if we can help you out.

Jeff

ws6killer

iTrader: (4)

I have a s60 with a trutrac for sale cheap if interested!

Gaunt

iTrader: (11)

Here is where I'm hung up on things a little bit.

Everybody keeps saying wavetrac over and over and over and over and over.

The wavetrac hasn't really been out THAT long, and there have been plenty of street cars with unnecessary amounts of horsepower that have used SOME type of currently available differential. Or do those people skip the differential and just run spools so they can call it a day? I'm just a little confused and have a hard time justifying the extra investment when I know people have made cheaper combos work and drive nicely.

Again, this car will be a stalled 4L80E.

Bob@BruteSpeed

iTrader: (16)

Before the Wavetrac, the higher horsepowered cars were limited basically to either a spool or a locker. Lockers can be evil bastards. Bob

Gaunt

iTrader: (11)

Bob, I've read through tons of your posts about how you would pick a spool over a locker, and I'm inclined to believe you, because I trust you and your knowledge.

Would I kick myself if I got a spool for a weekend warrior car? Really only cruising through the suburbs, never going to be caught in the rain (Arizona car... lol), etc.

From what I understand, spools need a little more tire to absorb some of the harshness, but does that apply to automatic cars? I would be rolling around on standard 315/35/R17 tires out back.

Bob@BruteSpeed

iTrader: (16)

Thanks. Bob Johnson (skydiver) has an '05 CTS-V with 865 rwhp, six speed and a spool. He drives it around Indy, and the spool doesn't bother him at all. Bob

cody161

iTrader: (18)

My car has a spool in it. When I first got the car I drove it almost every day for close to two months and then I went back to driving my daily driver on a regular basis. The back tires were wearing pretty fast becausae of the spool but that was the only thing that really bothered me. It does chirp the tires when you are making a tight slow turn, like in a parking lot or going through a fast food drive through.

Gaunt

iTrader: (11)

I talked to skydiver, and his experience is exactly as you describe. Plus, the way we use our cars is the exact same too...


I guess it's just because I haven't had any experience with either the locker or the spool, but a locker acts like a spool when it's locked correct? Am I right in assuming the real annoyance of the locker is when it unlocks/locks at speeds you aren't anticipating? I've almost completely ruled out a locker, but I need to know why it isn't the best of both worlds. The most I've gotten out of threads about the locker is people saying "Don't get it, it's evil" without giving too much in the way of why a spool is significantly better. They both scrub tires around turns, and the locker is louder?

ssvert99

iTrader: (26)

here's what I tell most people in this situation... if you have the coin go with the Wavetrac. its the best thing going for a 35 spline diff in a 9 inch right now, and you can't argue with a lifetime warranty.

but... if you would rather put the upgrade cost of the Wavetrac into something else then just go with the spool for now as it is for sure the lightest, strongest, and least cost of any diff unit on the market. if the spool doesn't work out so well for you the initial investment of the spool isn't so bad and you can sell it off. put whatever money you get back into a Wavetrac diff and simply just change it out. we can setup the axles the same so you won't have to do those twice.

the changeover from a spool to a Wavetrac will be a bit more cost in the end vs just getting the Wavetrac right up front, but if the spool works out for you then you will be way ahead. being you have a 4L80 trans i would probably opt for the spool in your case. street driveability wont be as bad with an auto vs a M6... all you have to do is give it a bit more gas in a slow speed tight turn vs a posi unit. we run spools in our cars on the streets as well... one A4 car, one M6.

as for a locker... we have sold some... not near as many as the Wavetrac now. the locker is designed for 4WD trucks. i'm not a big fan of them but they do work and until the Wavetrac was the only option for a diff unit in 35 spline. there is another 35 spline diff unit in the works but not on the market quite yet

garygnu

how much torque? with that much power go with spool and the biggest axles you can get.you are now caught in a hp vortec..you will want to make even more power ,build a rear that can handle twice the power that is where you are heading in the near future.

Bob@BruteSpeed

iTrader: (16)

See this review that was posted the other day, the guy did a great job of explaining how a locker operates. https://ls1tech.com/forums/gears-axl...locker-m6.html Bob

sixpack_2_go

iTrader: (1)

how much more does it cost to get a wavetrac when ordering a fab9 from MWC(assuming you are already going with 35 spline axles)? what are the advantages? from what i can tell, the wavetrac just came out recently and i haven't been able to find much info.i read the Wavetrac and Moser website but they don't say what power/torque level the wavetrac can withstand.