bigSS

When you go from a 10bolt w/4.10s to a 12bolt w/4.10s, will you lose any rwhp, ET, or MPH? This is assuming tractin isn't a problem.

Bear

iTrader: (1)

I'm pretty sure u loose a little. The 12 bolt is a little heavier. Upside is u could probably launch a little harder with the beefier rear.

Bob2of3

iTrader: (11)

I know everybody says that they lose rwhp when upgrading to the 12 bolt(I'd imagine its from inertial losses, ie turning a 7.5" ring gear vs a 8.875" ring gear) I don't know what the amount would be but like Bear said the 12 bolt will remove one of the driveline worries so you can let it hang out on the launch to make up for any losses on the dyno <img src="images/icons/smile.gif" border="0">

<img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />

nbm00ws6

iTrader: (4)

I was running 12.4's everywhere with a 10 bolt/4.10 combo and a alum. driveshaft on nitto's and launching at 3000 rpms. I installed a 12 bolt/4.10 combo with a steel driveshaft and couldn't better a 12.59 on ET Street launching at 5000 rpm's. I lost a couple tenths or close to it.
Tom

BIGBOS

Hmm thats interesting...

Get a little more power out of the engine and that # should go lower.. <img src="images/icons/smile.gif" border="0">

nbm00ws6

iTrader: (4)

Heads and T-1 cam helped out, new best in sig.
Tom

Nine Ball

iTrader: (38)

I lost about 13 rwhp going from a stock rearend with 3.73 gears to my 12-bolt with 4.10 gears.

But, it was definitely worth it! Tow trucks suck.

Tony

Colonel

I saw no difference in trap speed or ET when I went to the 9" from the 7.5" and again no difference when I went to the 12-bolt. I'm sure there had to have been some small loss but it was so small that I couldn't detect it.

BLUEBALLS ZZ

iTrader: (2)

this sort of makes me feel better. i dynoed and was still aprox 10hp off. i know it may be nothigng to most of ya. but i got guys out there with just cams with 20hp over my heads and cam <img src="gr_sad.gif" border="0">

Smoke_ur_5.0

iTrader: (2)

Well if you liked that Colonel then here's a little more. With stock 3.42's in the 10 bolt it pulled 342rwhp...switched to the 4.10's and pulled 338rwhp on the same dyno with no other changes <img src="gr_images/icons/wink.gif" border="0">

ChrisB

stock rear end with 3.42's -> 9" with 4.11's = 14rwhp loss.

My guess would be most of the apparent loss is due to gear ratio changes.


Chris

Smoke_ur_5.0

iTrader: (2)

Dynoed 348rwhp(when I still had just bolt ons) with the stock rear and 4.10's...switched to Moser 12 bolt with 4.10's and went to 344rwhp on the same dyno with no other changes.

No noticable loss in ET or MPH at the track.

Colonel

[quote]Originally posted by Smoke_ur_5.0:
<strong>Dynoed 348rwhp(when I still had just bolt ons) with the stock rear and 4.10's...switched to Moser 12 bolt with 4.10's and went to 344rwhp on the same dyno with no other changes.

No noticable loss in ET or MPH at the track.</strong><hr></blockquote>

Now that's really good information since you didn't change the ratio. Makes for an apples to apples comparison. <img src="gr_images/icons/cool.gif" border="0">

jimbob

iTrader: (4)

Here's another direct comparison <img src="graemlins/gr_xmas.gif" border="0" alt="[santa]" />

My 10 bolt with 3.73's made 405crwhp
After the install of "Strange 12 Bolt" I re-dynoed and came up with 394crwhp on the same dyno a few days later.

My trap speeds were off about 1 mile an hour, but the time didn't really change. Just goes to show ya how much track conditions play a roll.

Jim

Trevor @ Texas Speed & Perf.

iTrader: (3)

I dynoed 2 RWHP less with my Strange 12-bolt with 3.42's vs. my 10-bolt with 3.42's. I then swapped out to a CFDS, and it picked up 2 RWHP, so I was right back to where I started. <img src="graemlins/gr_xmas.gif" border="0" alt="[santa]" />