maddboost

iTrader: (11)

Tuning should get your 10 to 15 more hp and tq and clean up that A/F ratio nicely.

JZ'sTA

iTrader: (23)

Most people see between 1-2.5% HP loss through the 9" vs the stock to bolt.
Most M6's see a stock 10 bolt left on the track because the need a 9".
I think loosing a few donkeys is worth not blowing your rear end.
The 12 bolt is another option and from what I hear you dont loose quite as much but there is still a small HP loss vs the 10 bolt.

mike m

iTrader: (6)

your #'s are a bit on the low side you should give LG a call and see if he can give you any help with tuning and anything else he might recomend. good luck with your new setup.

JZ'sTA

iTrader: (23)

I dont believe you will pick up more HP through the band by ading fuel to richen your car and get your AF in the right spot.
Are cars put more HP down when they are lean. At the same time this is defentially not something you want to pick up HP. Runing lean is defentially something you need to take care of.

niphilli

I dont think this is right. I would bet there is close to a 30 RWHP difference between a 3.42 10 bolt and a 4.10 9 inch. I think RAGEMAN switched to a 9" when he was a bolt on car? Is Fireball running a 9" also? Check with these guys.

If you are taking the car back to the middle east you may want a conservative tune...Try 12.5:1 A/F on the dyno... Check with Abdullah on this board. You may also want to look into buying ATAP or EFI live so you can do mailorder tuning better after you have moved back .

mike m

iTrader: (6)

30 hp are you nuts its more like 10-15 tops.

niphilli

Dont quote me on this because I am not positive but I think 4.10s in a 10 bolt suck up about 7-10 RWHP... a 4.10 12-bolt from what I have read sucks up about 20 RWHP over a 3.42 10-bolt...and I know a 9" sucks up even more than a 12-bolt

CHRISPY

Before you call someone nuts know WTF you are talking about...

I have witnessed first hand 26-27RWHP from 10 bolt with 3.42's to 9 inch with 4.11's

mike m

iTrader: (6)

bspz28 lost nothing going form a 12 bolt to a 9 in. i think he either stayed with the same gear or even went bigger.

JF WS6

I believe I read a post from Slowhawk where he swapped the 10 bolt for a 12 bolt, that being the only change and lost about 20RWHP on the dyno. So with either rear you're looking at about a 20HP (give or take depending on gears) loss going from the 10/3.42's to a 12/4.10's or so.

PurdueWS6

Im all confused now guys

a friend of mine says 3-5rwhp loss from the 4.11s and my 9", some say 10-12, some say 26-30.

But i guess i would believe what someone says if he actually tried dynoing exact same set up just different rears.

Also as for tuning, I plan on taking it tomorrow to LS1 Speed Inc. just need to call them today and hope they can fit me into a spot tomorrow because my car goes into the container tomorrow, so i need to get the tuning done before then.

And niphilli i'll remember what you said regarding the ratio and let LS1 Speed know about that tomorrow!

gomer

iTrader: (13)

I hate to get off subject... but how much $$$ is it costing you to ship a car from the states to "over there"?

mike m

iTrader: (6)

ok ill say 20hp will that make every one happy???

taqwache

dont forget track times

CHRISPY

There are many factors here:

1) gear ratio/type/material
2) axle length, spline, weight, gun drilled or not
3) stock driveshaft reused? Aftermarket DS used when swap done?

Those all account for variances. Obviously a 35 spline 9 inch with 4.30 gears and steel DS will have more parasitic loss than a 9 inch 30 spline(Or gun drilled axles) with alum center section, lightweight gears and DS.



Chris

PurdueWS6

Around $4000 but thats for the WS6, a 67 Mustang, and my furniture and stuff in a 40 foot dry container.

Mahmood

PurdueWS6

4.11, 31 splines, iron center section, detroit locker, 2.5" 12mm studs, used the stock drive shaft thats all i know about it
does that help any Chris ??

taqwache - will get track times as soon as the car gets back home i won't just leave it at dyno numbers, i spent so much for the rear end, i sure would like to use it
Mahmood

niphilli

No one is trying to be a jerk here man, just trying to give Purdue some good info. I have seen numerous posts on this board showing 20 RWHP differences between 10 bolt 3.42 gear setups and 12 bolt 4.10 gear setups. I have also read on numerous occasions that the 9" sucks up even more power...Chris is right though it does depend to an extent on the axles & setup you run in your rear. All of this is Heresay because I have not done this swap myself, but I trust most of the sources on this board.

NataSS Inc

iTrader: (9)

I think 10-15 is about the norm.

Pro Stock John

iTrader: (34)

I think 10-15rwhp loss for your 9", nice numbers!

I'd do 12:1 on the AF since you will run a full point leaner on the street (13:1 on the street).

I did 475rwhp/505rwtq thru my 9" when I had my ARE 422.