I currently have dual air bags, poly bushings, ATR rear sway bar, and upgraded LCAs are on the way.......i was reading this months Car Craft magazine and noticed the article about the rear ends and how beefed up it should be for certain 1/4 mile times.....how much will a stock GN rear take???? Is there a limit on safety when you start going 11's or high 10's????? If so, what is recommended for an upgrade on a car running low 11's to high 10's???
How good is a stock GN rearend???
- Thread starter Vader 87
- Start date
"strength" wise the GM 8.5 is every bit as strong as anything...the weak points are the c-clips and axles....all of the above is good into the 10's....NHRA disagrees and says you need to dump the c-clips at 10.99.....
if you want to run into the 10's, upgraded axles and some type of c-clip eliminator is needed
for example, not much to gain by going to Ford 9" strength wise, just convenience wise if you like to change ratios
the Ford axles are nice because they bolt in and have no c-clips...
Moser makes a kit for our rear that uses the bolt in axles
if you want to run into the 10's, upgraded axles and some type of c-clip eliminator is needed
for example, not much to gain by going to Ford 9" strength wise, just convenience wise if you like to change ratios
the Ford axles are nice because they bolt in and have no c-clips...
Moser makes a kit for our rear that uses the bolt in axles
C
Cakes
Guest
Well let me just say this....Jack Cotton is running mid 9s on a completely original, beefed rear end. They can be made to hold plenty of power I guess it all depends on how deep your pockets are. A lot of guys go to a 9 inch but from what I heard from Jack in certain classes you are not allowed to run anything but stock equipment. Hope this helps some.
- Joined
- May 28, 2001
Beefy rearend??
For a minute there, I thot you were referring to one of my ex-wives!!
The axles can be ordered w/ the c-clip deals already on them. The hsg end has to be cut, another set of holes drilled and then they bolt into place. About $350 a pair.
Limited slip assy, [EATON] bout $400.
New gear and brgs, bout $300.
Rear girdle, bout $150.
I go lo 10 @ 3700# [damn, there's another reference to my ex's rearend!!] I have the Moser axles, Auburn posi and a new 3.42 gear. No problems yet.
Back to checkin out the GF's rearend!!
For a minute there, I thot you were referring to one of my ex-wives!!
The axles can be ordered w/ the c-clip deals already on them. The hsg end has to be cut, another set of holes drilled and then they bolt into place. About $350 a pair.
Limited slip assy, [EATON] bout $400.
New gear and brgs, bout $300.
Rear girdle, bout $150.
I go lo 10 @ 3700# [damn, there's another reference to my ex's rearend!!] I have the Moser axles, Auburn posi and a new 3.42 gear. No problems yet.
Back to checkin out the GF's rearend!!
N
NastyGn
Guest
Just my opinion but the 8.5 is a good rear end and with the right stuff can handle a 3700# car into the 10's for sure.
Where I think they get weak is in the 60' times, and not just the
ET of the car. Mine did fine with 1.4 60' times but when I got the car to run low 1.3 60' times it only did it 3 times and tore out all the teeth on the ring gear (all brand new stuff). I had about $1,500 into the 8.5 (30 spline axles, detroit locker, c-clip elem, heavy duty bearings and a new ring and pinion gear) and it was only about 3 weeks old.
Have fun and take care
Where I think they get weak is in the 60' times, and not just the
ET of the car. Mine did fine with 1.4 60' times but when I got the car to run low 1.3 60' times it only did it 3 times and tore out all the teeth on the ring gear (all brand new stuff). I had about $1,500 into the 8.5 (30 spline axles, detroit locker, c-clip elem, heavy duty bearings and a new ring and pinion gear) and it was only about 3 weeks old.
Have fun and take care
from the standpoint of NHRA tech, 10.99 is the same as 9.99, so if you keep your c-clips, you could have problems running into the 10's (you also need an SFI balancer and trans blanket for 10's)
I would suggest you just run what you got until something breaks....many guys with low 11 sec cars get away with stock stuff for a long time.....there is the safety issue with the c-clips tho
I would suggest you just run what you got until something breaks....many guys with low 11 sec cars get away with stock stuff for a long time.....there is the safety issue with the c-clips tho
I have Eaton posi, 30 spline Ford type bolt-in Mosers (no c-clips), and stock 3.42 gears (axle tubes are welded and gusseted, HD bearings, TA cover, etc)
I ran just stock stuff into the very low 11's for a long time until my posi gave up and then upgraded....I started "thinking" about what happens if a c-clip breaks when my trap speeds were regularly around 120+........
I ran just stock stuff into the very low 11's for a long time until my posi gave up and then upgraded....I started "thinking" about what happens if a c-clip breaks when my trap speeds were regularly around 120+........
