Gary, I used the hole saw method on both the Red 12 and the "Denny's" car and liked it. It also removes lots of weight from the outside of the car and resulted in at least 2 seconds per lap.

Jim

Jerry, Ken and I did my torsion bars yesterday using Joe's method and spreadsheet. No hole saw. We dropped the rear end. About 10 hours of labor...and 50 sore muscles later, the car looks and drives great!
We dropped the rear about 3".
Didn't do the bushings though. It was getting late...and the bushings looked good enough. By that time I just wanted a hot shower and a cold drink.

Thanks so much guys! I really appreciate you sacrificing your Sunday to get dirty and sore to help me!

Big Dog wrote:


man, Jim...you know how to find a silver lining for anything!
Question: Did you tap threads in the ends of the new bars, weld a tab on them or just go as is?

Now that I know what's involved, that was a pretty big favor by Ken and Jerry. But that's why NorCal 944Spec has the rep as the nicest guys out there!

Ok,need some advice. Here's where I stand.

- I cut the holes in the rockers. I removed the endplates from the t-bar covers and pulled the old bars out.
- I raised the rear trailing arm until the shock bolt hole lined up with the free hanging shock.
- I installed one new t-bar, then on the other side I was stuck because my new bars have about 1/2 inch more splines on the outside end. That meant that I couldn't align the inner splines when pushing it in from the end, so the other bar wouldn't go in.
- I gave up and loosened everything enough to drop the torsion tube on one side, removed the spring plate cover, installed the bar to match the other side spring plate angle. Reassembled and set it on the wheels.
- Car is level, with the new bars in, but the car is still about the same height as when I started after days worth of work!

So, what to do?
Should I have tabs welded on the bars and try again to reindex them through the holes? Is there a trick to getting them aligned into the inside splines?

If I drop the tube again, and just raise the trailing arm another 3" from where it is and reinsert the bars, will that be my final height?

Should I start all over, measure everything again and drop the whole rear and use the procedure posted here?

This photo is a key if you are pulling the assembly.




When I do t-bars I take this measument to the center of ht hub with the old t-bar and then do it again with the new t-bar. Every inch this is different will change the ride height with the same size bar.

So if it is 9" now, change it to 6" and it will lower the car 3". It gets complex when changing t-bars since they compress different due to their stiffer rate. That is what my spreadsheet is trying to calcuate.

Normally there are two numbers that differences in this dimesion.

First number is inches change due to the stiffer rate. A 9" measumement stock may need to change to 8.5" due to the siffer springs alone to achieve the origial ride height.

Second number is ride height change. That could be 2" lower. So 9 becomes 7".

So both numbers add so that 9" might need to be 6.5" to lower the car 2" and install stiffer bars. Seems like you just compensated for the stiffer spring.

Just my opinion and I'm not the smartest guy here; weld on two tabs that have a hole to the t-bar, you may be able to do it with the bars in place, and then work on pulling/adjusting for ride height. A slide hammer with a hook on it to hook in the tab makes it easyer. Be gentle, they will come right out/in when the planets are aligned just right.
From what I have learned and when doing it by myself; use three floor jackes if you can get them, disconnect both shocks, use two jacks to lift the body and one under the tire to make the minute up/down adjustments to remove bar then adjust tire height with the jack and reinstal bar, do the same to other side then lower the car to see how it sits. If you are looking for exact results, corner weights will come into play at this time. Some cars will not sit level with good corner weights but the above method should get you close.
Hope that helps. I considered the t-bar adjustment in our cars to be the true suspension initiation.
Lee