Help telling rear torsion bar size

Tom '74 911 · 11-03-2005, 09:03 AM

Hi -
I just removed my rear torsion bars, but can't decipher the numbers to tell the size. On the ends it has some stamped numbers along w/the "R' and "L". They are:
1128
1193

Are they size 28? I don't see any other markings on the bars. They are painted white and are hollow if that helps.

Thanks,
Tom

safe · safe's Garage

How about meassuring them?

Tom '74 911 · 11-03-2005, 10:06 AM

DOH! Sometimes it's hard to see the forest thru the trees. I'll pull out my calipers.
Tom

juanbenae · juanbenae's Garage

24.1mm

ttweed · ttweed's Garage

Quote:

Originally posted by Tom '74 911

Are they size 28? I don't see any other markings on the bars. They are painted white and are hollow if that helps.

If they are white, they are probably Sway-a-Way bars, and the numbers you posted are consistent with that. OEM T-bars are orange or black, and Sanders bars are unpainted.

If they are hollow, they cannot be OEM either, as all the Porsche factory bars are solid, and measurement of outside diameter on a tubular bar will not correspond exactly to the effective rate of a solid bar.

TT

randywebb · 11-04-2005, 12:48 PM

yes - but measure anyway -- someone might be able to correlate the measured dia. with an effective springrate...

Tom '74 911 · 11-04-2005, 12:55 PM

I measured them last night, but didn't write the number down - I do remember it wasn't an even number. I'll remeasure tonight or tomorrow and post it.
Tom

Tom '74 911 · 11-04-2005, 03:10 PM

O.K. - they measure 29.4mm ±
Once again, definately not stock. They are painted white and are hollow and have the #'s:
1128
1193
stamped on one end.

Thanks for the help,
Tom

Tyson Schmidt · 11-04-2005, 05:10 PM

Quote:

Originally posted by Tom '74 911
O.K. - they measure 29.4mm ±
Once again, definately not stock. They are painted white and are hollow and have the #'s:
1128
1193
stamped on one end.

Thanks for the help,
Tom

Probably 28mm effective rate. That means that they measure 29.4, but have the same rate as a 28mm solid bar.

randywebb · 11-04-2005, 05:30 PM

Ha - Tyson to the rescue...

Now -- are you happy with that stiffness?

Tom '74 911 · 11-04-2005, 07:46 PM

"Now -- are you happy with that stiffness?"

By the time you get done reading this, you're going to be thinking, "I had ask?"

Honestly, I don't have anything to compare it to. I'm pretty new to all this. I bought my car a few months ago and am getting to know it slowly. All I know is that I love it! It seems pretty stiff, but that's OK w/me. I'm used to driving a truck and a subaru. I'd rather have it be tight and quick than not.

Some base info: The PO had set up the car for autocrossing. It was slammed to the ground. It's a '74 w/a '77 2.7 w/all the updates and then some. He said it had been corner balanced etc... but that was quite a while ago - like 8+ years maybe. Plus it had been a dailey driver for a while as well.

A few weeks ago, I took it to get aligned at a shop that came pretty highly recommended - it's pulled slightly to the right since I drove it home for the first time. End result after driving for 2.5 hours to the shop (I live in the middle of nowhere) spending the entire day - from 9AM 'till 6:30PM at the shop - they couldn't fix it. So I spent an entire day and didn't get any answers. They couldn't even give me a place to start looking for answers - like this looks bent or that looks crooked etc... they thought everything looked totally straight. I think they were as frustrated that they couldn't fix it as I was pi$$ed that they couldn't fix it. They/I tried everything from swaping tires to misaligning it on purpose to pull the other way. It still pulled right.

Anyway, there were some things that didn't quite seem right w/the car as far as ride height and side to side levelness was concerned. The alignment shop also raised the front end - I asked them specificly if they had 'cause it looked quite a bit different after they were done. They guy said, "not much, just slightly." Well I got home and measured and his "just slightly" was like 1 1/2" - which didn't seem slight to me at all.

So. . . - sorry, this is turning into a long story - I decided to start from scratch and reset the ride height the way I want it which is a tad higher than the way it came - still quite a bit lower than "euro height" and to go thru the suspension while I'm at it to verify that it's all O.K. The front went smoothly as I didn't replace any bushings, but just lowered it back down some and leveled it off - just simply using the "tripod method". Now, I'm into the rear. I started knowing full well I'd have to reindex the TB's to raise it up a little. Of course once I got in there, the spring plate bushings were in sorry shape and I couldn't knowingly put it back together like that, so . . . I'm doing new Neatrix bushings and new rear sway bar bushings - which were shot also (I'd have really, really liked to do the Elephant Racing bushings thru-out, but it's not in the budget at the moment).

Blah, blah, blah - so I had my rear TB's out - not an everyday occurance - and just wanted to size them so I have a reference to start with. I thought I'd also try out that ride height calculator when I put it all back together. (yes, I took a lot of measurements before I tore it all apart).

So where does all this leave me? Ummm, I'm not sure. At least I now know what size my rear TB's are! I do actually enjoy taking my new toy apart and putting it back together - hopefully better than the way I found it. I've become a little obsessed actually - just ask my wife. There is another thread here running at the moment about what you could do to your car w/$10k to spend. I'd sure love to try - and plan to, just spread out over 10-15 years.

After all this, I took it for a test drive after doing the front, but before the rear. I didn't reattach the front sway bar - just to see - and I'll be darned if it didn't track straight as an arrow. Maybe a bent front sway bar was causing the pull all along? I dunno. It snowed about 6" last night anyway - so winter's started here and I've got all winter to tear it apart and put it back. Although I'm already feeling the 'jones to get it back on the road after a few weeks of looking at it up on jackstands in my garage.

Sorry for the long answer,
Tom

randywebb · 11-04-2005, 07:54 PM

"I do actually enjoy taking my new toy apart and putting it back together"

- In that case, I have something that will be longer than your last post -- replace every piece of rubber in the car's suspension. First, replace the rubber brake hoses....

Check thru the repair docs with the car (receipts) to be sure it hasn't been done w/in the last 7-10 years. If not, then do it.

Tom '74 911 · 11-05-2005, 05:43 AM

Yeh - I've thought about replacing all the rubber in the suspension. A lot of the front end seems to be in pretty good shape. I'm basicly doing the entire rear except the trailing arm bushings. I'm going the more affordable route at the moment w/the thought of really going big in a few years. I met a local guy who is rebuilding his '72± and converted to all coilovers. That looks like the kind set-up. Much easier to make adjustments on - although it'd probably take me many years to understand the dynamics of them all.

The car came to me pretty well upgraded with SS brake lines, new(er) shocks, TT rods w/spacers, and a rebuilt engine (30,000 mi. ago). I'm hoping to just extend the current set-up for a few years while slowly getting to know it better and then do an entire tear down and rebuild w/new paint from scratch and new interior etc....

But meanwhile. . . I'd like it to be a great daily driver for me, which means no pulling to the right!

Tom