Jenny Craig on my Suby continued tonight with installation of the Oswald Rear Bumper Beam.
This install was a bit more of a PITA. The main annoyance was the charcoal canister getting in the way of one of the 17mm bumper bolts and having to undo a ton of things like the tail lamps, license plate harness, etc. There are even some rivets you need to drill out but "luckily" my rear end got smashed a few years ago and the idiot truck driver actually saved me some work; none of the rivets were left on my car lol.
The rear bumper beam weighs 7 lbs vs. the stock 28 lbs. I also got another dirty little piercing to match the front one I also went ahead and ditched the spare tire and jack for another good 31 lbs (comes out at the track anyway).
Removal of the 60+ lbs from the front end really made a huge difference driving around today. Since most of the weight was at the part of the car with the highest polar moment of inertia, the effects were immediately noticed even during regular cornering. There is less push/understeer/dive and the car feels more "point and shoot". Even acceleration and braking seems to have improved by a noticeable amount. I noticed it especially just rolling around between stop signs.
I'm now glad I did these mods despite their somewhat high price. I wouldn't place them ahead of things like swaybars or Stage 2, but they're definitely something to consider when trying to go faster. I would take weight reduction over HP any day because it helps with side to side as well as braking.
Now the outstanding problem is my damper setup. The BC's harsh ride are becoming more apparent due to the weight reduction. Less weight = higher natural frequency = uncomfortable. I'm also hoping I didn't make the rear end too light so that it becomes twitchy, but I guess I'll find out tomorrow.
Weight reduction so far:
- Lightweight battery 28 lbs
- Subframe 14 lbs
- Front bumper beam 22 lbs
- Rear bumper beam 21 lbs
- StopTech BBK ?? lbs (lighter than 4-pots)
- Forged track wheels 15-20 lbs
TOTAL: 100+ lbs