Quick performance 9" impressions
#1
TECH Fanatic
Thread Starter
Quick performance 9" impressions
So I purchased a 9" for an fbody from QP and finally got it all buttoned up. I am not a build thread kind of guy so I didn't take step by step pics but I can explain how my experience was. The welds and overall build quality was very good. Thick clean welds and a smooth bare metal finish. Large (chrome?) Fill cap on the front diff housing which is easily accessible. Drain plug doesn't leak once you actually tighten it up...had minor issues getting carrier to slide onto the housing but a few taps with a hammer ((need to bend 2 studs very very slightly)) the carrier slid into place. Yes, it is heavy. Painted it with por15, 3 coats. Came out okay. Went to a rack and axle shop and got a driveshaft 1" longer than my stock shaft. Steel with 1350 joints. Fits great and was only 289 bucks. I installed the rear and noticed spring perches we're not aligned, I placed the blame on the LCA mounts. I was wrong, the BMR arm was waaaay off where it needed to be when they shipped it to me (Car is stock height) so I corrected that problem and everything came together much better. Had to drill PHB and shock mount holes bigger. I believe to 9/16". Very easy. Had to cut torque arm bracket as well as the housing bracket, took 10 minutes with a DeWalt angle grinder. Spray painted the bare metal cuts with a sweep or two of black caliper paint. Had to cut ebrake brackets as well and bolted them to the upper hole of the LCA bracket. Works perfect. You may want to paint them if you care enough because they will be uglier and rustier than the rear. Got some spohn sway bar mounts (19mm) 70 bucks, look great and fit great. Brake lines will need to be done professionally but for now I bent stock lines by hand and wrapped areas where rub could occur in thick heater hose. I then zip tied that with heavy duty ties around the tubes. Temporary but sturdy. GM decided to use two different fitting ends for the brake lines so getting new lines pre fabbed from AutoZone with two of the proper fittings isn't going to happen. Make sure you tighten the torque arm bracket bolts before they go in otherwise it may be hard to access those bolts under the car. The top heim joint on the housing is hard to access as well but locking pliers and an extension help a lot.
After I got it back on the ground and took it out I am very happy with it. Haven't driven on the freeway yet but anywhere from 0-50 makes no noise at all. Break in is straight forward. Just granny it for 500 miles and change oil. I got the 31 spline true Trac with no abs or Trac control and 3.70 gears. Very responsive throttle response and the car still drives straight and feels planted. The rear was 2500 bucks shipped plus the little things like oils, grade 8 bolts and a few new tools and sway bar mounts. Torque arm clears the tunnel easily and nothing rubs, bangs or taps.
I would recommend this rear. Total investment was about 2800 bucks. Not including suspension which I already had anyways.
After I got it back on the ground and took it out I am very happy with it. Haven't driven on the freeway yet but anywhere from 0-50 makes no noise at all. Break in is straight forward. Just granny it for 500 miles and change oil. I got the 31 spline true Trac with no abs or Trac control and 3.70 gears. Very responsive throttle response and the car still drives straight and feels planted. The rear was 2500 bucks shipped plus the little things like oils, grade 8 bolts and a few new tools and sway bar mounts. Torque arm clears the tunnel easily and nothing rubs, bangs or taps.
I would recommend this rear. Total investment was about 2800 bucks. Not including suspension which I already had anyways.
#2
TECH Fanatic
iTrader: (6)
Thanks for the write up. I just bought a used housing and 31 spline axles for my car. I plan to run a 4" mufflex exhaust and already have a UMI chassis mounted TQ arm. I also plan to remove the rear spring isolators to drop the rear a little and still clear a 28" radial.
#3
12 Second Club
I can't believe I missed this. I have been wanting a QP 9" for a while. I was wondering how it fit. It sounds like some custom fabrication is required. I'm not even going to think about trying this swap myself.
So, was the longer drive shaft required?
So, was the longer drive shaft required?
#4
TECH Fanatic
Thread Starter
yes, I brought mine to some local guys and told them what I had and I needed it to be 1" longer than this OEM unit. Worked out perfect.
#5
12 Second Club
Thanks for the info. Now I know to plan on buying a new driveshaft too. I hear there is a local company that makes good drive shafts, so it shouldn't be a problem.
#7
12 Second Club