studderin

iTrader: (28)

I wrote this on a NewYorkFbody, figure I'd post it on here for some good info., sence most don't get to do a before/after like this.

http://www.newyorkfbody.com/viewtopic.php?t=4344
Why drivetrain power losses, and dyno #s dont mean ****


This is a before after on my car. No tunning changes, same wheels, and mods. Gear change was my stock 10bolt 3.42s (now in somone race ready for the ":spry: And my s60 with 3.73s I bought local form PM performance. :tup:


weight diffrence
10bolt 150#
s60 196#

track timers
10bolt 12.50 112.5
s60 12.21 @113.9

http://www.nyspeed.com/forums/showthread.php?t=31547
here is a post on my last dyno

s60 install post
http://www.newyorkfbody.com/viewtopic.php?t=3928

Power loss
3.42 10bolt 331.18whp 350.34 wtq
3.73 s60 316.43whp 340.39 wtq

_JB_

iTrader: (33)

It did zap some power though, I figured it would take MAYBE 10 horse max.

Avengeance

iTrader: (4)

Rule of thumb is 5% correct?

Grn4fbody

iTrader: (2)

Wow, wonder how much a 9inch robs?

Not like it matters since you ran faster

Avengeance

iTrader: (4)

From what Ive heard the S60 and 9" both suck up about 5%.

When I dynoed with my 10 bolt with my old fuel system it made 561rwhp/541rwtq. After installing a 9" along with all the new fuel additions it did 568rwhp/551rwtq. Add 5% to those numbers and it was just about what I had expected with the new fuel additions... 596/578.

Coincidently the OPs numbers, at least in the HP, reflects a exact 5% loss... TQ was a 3% loss.

James Montigny

iTrader: (13)

Interesting, I was under the impression the 9" lost twice as much as the S60 and the 12bolt somewhere in between.
That's one of the main reasons I was looking at the S60.

kenSS

iTrader: (1)

the 9" robs more power than any of them. cuz of offset pinion.

wrd1972

iTrader: (12)

Yes the 9" robs the most power again due to the more lower offset pinion. But this offset is what gives you the greater strength due to more tooth surface area contact. The S60 is supposed to have the most efficient tooth to tooth contact but you are having to turn all that additional mass. Of course the 9" has much larger mass compared to the 10 bolt.

DVS99TRANS

iTrader: (7)

That's the reason I bought one, don't hear them breaking as much. Although alot more people have 9" unfortunately so you won't hear it as much. Everything in the S60 is bigger so I figured inheritely stronger and the offset pinion allows better power transfer. A majority if the BIG turbine guys have them, so I figure that's what drew my attention to them. Nice to see this done, I thought the S60 felt alot heavier than that though. Well I'm just a little guy so... lol.

SIC LSX

iTrader: (10)

gears is what made it faster

Grn4fbody

iTrader: (2)

I think you lose the LESS amount with a 12 bolt james

AChotrod

iTrader: (17)

I did this test also but went with 4.10s from 3.42s I lost alitte less than you did.
S60 rules!!

hsutton

The thing that makes the 9" stronger is the pinion is supported at both ends. It doesn't just hang out there with no support like the 12 bolt and Dana 60.

RENE'S RAGE

iTrader: (96)

I also think going to a deeper gear made the car quicker.

VTC_WS6

iTrader: (9)

Sounds about right, I went from 430whp with the stock 3.42s to 397whp with the S60 (4.10s), but there's a 10+ whp loss from running the N2O tune vs. the N/A tune, figure I lost about 20-ish whp which would sit right around 5%.

James Montigny

iTrader: (13)

Funny how fast 6% adds up LOL

why me

i like the s60 cuase i can get a 35spline posi. but the gear rang sucks. i want to stay around 3.00 gear or 3.25 gear. and the lowest they got for the s60 is 3.54 that sucks.

jetlag

iTrader: (32)

Your S60 was only 46lbs more than the 10 bolt?!? That doesn't seem right... ?


Edit: Damnit, you guys made in participate in a thread dig... fail

James Montigny

iTrader: (13)

Ordered mine today