|
how much will a 8.75 take?
#1027907
07/07/11 08:33 PM
07/07/11 08:33 PM
|
Joined: Jun 2005
Posts: 4,041
michigan woods
imfixinmopars426
OP
master
|
OP
master
Joined: Jun 2005
Posts: 4,041
michigan woods
|
what is the limitations of a back braced,stock axles,sure grip 8.75 in a sticky tire car? we hope to run in the 10's,if not 9's. it is a street car,and changing gears back and forth. so lets hear about what will break,at what hp,and or et's...thanks,guys,mike
|
|
|
Re: how much will a 8.75 take?
[Re: imfixinmopars426]
#1027909
07/07/11 08:44 PM
07/07/11 08:44 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
I run a 8.75.... its not the power it can take... its the weight... JMO... if your over maybe 3000-3200 lbs and have any decent power you will break it... with stock axles you have 2 weak points... the carrier caps and the axles 
|
|
|
Re: how much will a 8.75 take?
[Re: imfixinmopars426]
#1027912
07/07/11 09:59 PM
07/07/11 09:59 PM
|
Joined: Jan 2003
Posts: 12,085
Benton, IL.
DaveRS23
Special needs idiot
|
Special needs idiot
Joined: Jan 2003
Posts: 12,085
Benton, IL.
|
My Cuda street car will pull a 1.5 60', and run 6.9 in the 1/8. The converter will flash to 4,000. The 8 3/4 lives okay. But you will need to control the pinion angle to keep from twisting the rear joint out and the stock axles will twist even before this level. In my opinion, if you're tires are hooking up okay, it is your car's weight combined with the hit at launch that will find the weak points in the drive train. The heavier the car and the harder the hit, the shorted the life. My Cuda weighs 3,450 with me and fuel. I usually get 3 or 4 years out of rear end, racing 8 or 10 times a year. When my cars 60' in the 1.8s, I rarely have any rear end trouble at all. As the 60' gets quicker, things start to break more often. 
Master, again and still
|
|
|
Re: how much will a 8.75 take?
[Re: BLONDE BARRACUDA]
#1027916
07/07/11 11:12 PM
07/07/11 11:12 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
I had over 600 passes on a stock one with a back brace then it spit the caps off... that was at 2450# with a 1,26 60'... now I have a alum center in the same housing with a 1.19 60'
|
|
|
Re: how much will a 8.75 take?
[Re: MR_P_BODY]
#1027919
07/07/11 11:43 PM
07/07/11 11:43 PM
|
Joined: Jun 2010
Posts: 469
Tennessee
steeldust
mopar
|
mopar
Joined: Jun 2010
Posts: 469
Tennessee
|
Quote:
I had over 600 passes on a stock one with a back brace
then it spit the caps off... that was at 2450# with
a 1,26 60'... now I have a alum center in the same
housing with a 1.19 60'
Man you must be doing some thing right if your doing that with a 8 3/4 with stock axles. 
|
|
|
Re: how much will a 8.75 take?
[Re: steeldust]
#1027921
07/07/11 11:56 PM
07/07/11 11:56 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Quote:
I had over 600 passes on a stock one with a back brace
then it spit the caps off... that was at 2450# with
a 1,26 60'... now I have a alum center in the same
housing with a 1.19 60'
Man you must be doing some thing right if your doing that with a 8 3/4 with stock axles.
Axles werent/arent stock... if you run in the 9s
and faster you must have aftermarket axles... I
never broke any axles but everyone thats ever been
in my car has twists in them
|
|
|
Re: how much will a 8.75 take?
[Re: imfixinmopars426]
#1027922
07/08/11 12:05 AM
07/08/11 12:05 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Also... a couple of things that help them live... if you run a 489 case... dump the crush sleeve for a solid spacer... also you can add the aftermarket caps or put load bolts in the back of the housing so they touch/ slightly load the caps... keeps them from flexing as much so they are less likely to break
|
|
|
Re: how much will a 8.75 take?
[Re: MR_P_BODY]
#1027923
07/08/11 12:34 AM
07/08/11 12:34 AM
|
Joined: Jun 2010
Posts: 469
Tennessee
steeldust
mopar
|
mopar
Joined: Jun 2010
Posts: 469
Tennessee
|
Quote:
Also... a couple of things that help them live... if
you run a 489 case... dump the crush sleeve for a solid
spacer... also you can add the aftermarket caps or
put load bolts in the back of the housing so they
touch/ slightly load the caps... keeps them from
flexing as much so they are less likely to break
I run i think when i run a 8 3/4 a 452 they have no crush sleeve and bigger bearings but my car was 3,400 lbs i had a 1970 GTX i run 9.0s 1/8 mile it was all stock it weight 3,775 lbs and it was a 4 speed car and i would twist the axles i would leave at 5,400 rpms with 9" slicks. 
|
|
|
Re: how much will a 8.75 take?
[Re: MR_P_BODY]
#1027924
07/08/11 12:37 AM
07/08/11 12:37 AM
|
Joined: Oct 2007
Posts: 3,978
Hilltown Pa
1967dartgt
master
|
master
Joined: Oct 2007
Posts: 3,978
Hilltown Pa
|
I have been 1.41 to 1.40s for 10 years on a spool and 35 spline axles and backed braced.Can't count how many passes but alot. Car weights 3300 lbs and broke one ring gear about four years ago so mabe I have two more out of this set.
Brett Miller W9 cnc'd heads
STR Chassis fabraction
|
|
|
Re: how much will a 8.75 take?
[Re: OA5599]
#1027925
07/08/11 01:42 AM
07/08/11 01:42 AM
|
Joined: Aug 2005
Posts: 989
WI, USA
67dodge67
mopar addict
|
mopar addict
Joined: Aug 2005
Posts: 989
WI, USA
|
Quote:
So I'm guessing a 3500 lb with driver, low 1.60s 60ft Cuda running mid to low 11s with 3:91s in the 8 3/4 and a tight 10" converter is a ticking time bomb with M/T Drag radials?
 I had a 742 case 8 3/4 that kept going south (3x too many) in my 67 Coronet, 1.65 60ft, 11.80s, same gears, same tires as yours. Got a dana. Never looked back. 
|
|
|
Re: how much will a 8.75 take?
[Re: 1967dartgt]
#1027926
07/08/11 01:44 AM
07/08/11 01:44 AM
|
Joined: May 2003
Posts: 2,117
Cleveland Ohio
10secGTX
top fuel
|
top fuel
Joined: May 2003
Posts: 2,117
Cleveland Ohio
|
I did well with my spooled moser axle 8 3/4, but on the starting line it was always in the back of my mind....was this going to be the pass ? I was foot braking a 3600 + car with a Big block. But 2 yrs ago at the Mopar race at Norwalk, the guy pitted next to us was trans braking with a 8 3/4 and broke the rear and replaced it an hour later, in the burn out box he nearly lost his feet, the 727 grenaded and came through the floor. For Me that was enough foolin around with 8 3/4's ...my 2 .
|
|
|
|
|
![6719043-005[1280x768].JPG](/ubbthreads/ubbthreads.php/ubb/download/Number/107137/filename/6719043-005[1280x768].JPG){kind=link}
