30mm front sway bar art pics
09-01-2010, 10:44 AM
#16
Rennlist Member
If there was enough interest, we could produce the 21mm bar. We almost did when we decided to build the 5 way 19 (3/4") , since the 21 (7/8") was going to be 85% stiffer, and that sounded like to much. You can stiffen the bar by going to solid bushings and get about the same thing so it didn't make sense. More or less a 19 with solid = 21 with rubber. Or so said the bar manufacturer. Since there isn't a rubber for a 21, either that would have to be molded, or solid which would make it even stiffer. Since there is a typical front to rear ratio to work around, a 21 on the rear would/should require something larger then a 30 on the front.
The factory rubber bushing for the 21mm bar is 477 411 313 D. A 21mm bar is an optional bar for some of the 911s, 964s for sure - so the bushing is still available from porsche.
What is interesting, the 21mm bushings that were used on the Cups (at least the '87 US Cup/Escorts) were regular rubber. But I have a pair of bushings that came on a new Cup bar that was bought years ago, probably came from Porsche Motorsport Parts Dept, that are a white solid plastic with the same factory part number on them.
I never had a way of actually measuring rates, but from track testing, I would say that the 21mm bar full soft is noticeably stiffer than the 19mm (968 bar) full stiff.
Progressive front springs (max between 370-410 lb/in depending on source) w/ 30mm front bar; 25.5mm rear t-bars w/ rear progressive coilovers (max between 270-370 lb/in depending on source) w/ the 21mm rear bar. Bilstein Cup shocks or Koni double adjustables depending on US or RoW. Bushings were a mix of harder rubber and some solid mounts on the rear torsion bar carrier.
Agree - I played quite a bit with rear swaybars to adjust handling (16s to 21s), and all else equal, you do need a lower rear spring rate to accommodate the use of the 21mm rear bar. If using springs in the range of 400-500 lb/in, I would estimate that you would want to drop the rear rate by 50 lb/in if going from a 19 to a 21, or 100 lb/in if going from a 16 to a 21. Can be looked at this way too, if the car is pushing and you need more rear stiffness, the 21mm rear bar alone is often enough to dial out understeer w/o changing spring rates.
Last edited by Oddjob; 09-01-2010 at 11:04 AM.
09-03-2010, 06:06 PM
#20
Rennlist Member
The 968 M030 front bar is the same part as the 87+ Turbo Cup bar, same factory part number. So, yes - identical.
The Cup rear bars are the 21mm 3-way adjustable bar. The adjustable ends are noticeably beefier than the 19mm 968 bar. They are also noticeably stiffer than the 19mm bar. When still available, up to about 12 years ago, they were over $500 from Porsche motorsport.
The Cup rear bars are the 21mm 3-way adjustable bar. The adjustable ends are noticeably beefier than the 19mm 968 bar. They are also noticeably stiffer than the 19mm bar. When still available, up to about 12 years ago, they were over $500 from Porsche motorsport.
Yea, I remember they went for a lot of $$$
I bought both the front and rear from Andial... My rear end still hurts
Pun intended Here is a picture of what I did ... Not real pretty but those bushing weren't going anywhere ... You are correct for the most part they don't come out unless something very dramatic happens .. In my case it was going over some ridiculous hilly terrain in Monterey CA
09-04-2010, 02:59 AM
#22
Rennlist Member
09-04-2010, 09:09 AM
#23
Rennlist Member
The factory c-clips are for the end bushings on the 30mm bars, not these intermediate brackets/bushings. They just clip on the end of the bar and retain the bar within the drop link bushing.
The common problem with the intermediate mounting bushings is when oil or power steering fluid gets on the passenger side one, and over time the rubber swells and degrades - makes the bushing creep or almost "ooze" out of the bracket.
But with that said, my escort/cup car came with clamps (same as the McMaster clamp) on the inboard side of the intermediate mouting brackets/bushings. And also had Kelly Moss support brackets installed. I had the bar and brakets powder coated and have not yet reinstalled the clamps, mostly because I am not certain of their usefulness.
The common problem with the intermediate mounting bushings is when oil or power steering fluid gets on the passenger side one, and over time the rubber swells and degrades - makes the bushing creep or almost "ooze" out of the bracket.
But with that said, my escort/cup car came with clamps (same as the McMaster clamp) on the inboard side of the intermediate mouting brackets/bushings. And also had Kelly Moss support brackets installed. I had the bar and brakets powder coated and have not yet reinstalled the clamps, mostly because I am not certain of their usefulness.
09-04-2010, 09:13 AM
#24
Rennlist Member
Not my original work, but I have left it because they are functional and I dont have an extra set of koni jam nuts lying around.
09-04-2010, 04:41 PM
#25
Rennlist Member
I also had them on the end bushing as well but didn't have a picture of it
I think your assessment regarding the bushings deteriorating is indeed that case with mine ( if you look at the picture ) That's what appears to be case ..
Any sugesstions as to a replacement ... I really dont want the filling to come out of my teeth ...
PS Man those Kelly Moss support mounts are really beefy !!
09-04-2010, 05:38 PM
#26
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thought you guys might enjoy these pics
Supposedly this is a turbo cup front sway bar but it is identical to the 968 M030 bar. I have a 21mm rear adjustable sway that is also supposed to be factory turbo cup equipment and is a little bigger than the 968 19mm rear M030 sway bar.
Supposedly this is a turbo cup front sway bar but it is identical to the 968 M030 bar. I have a 21mm rear adjustable sway that is also supposed to be factory turbo cup equipment and is a little bigger than the 968 19mm rear M030 sway bar.Did dfrifta 944 get in touch with you about that white nose piece?
I sent him your way. He needs one for my old car.
E
09-04-2010, 10:29 PM
#27
Addict
Rennlist Member
Rennlist Member
Thread Starter
09-05-2010, 10:20 AM
#29
Rennlist Member
Few pics showing some of the things discussed:
C-clips on the ends of the front 30mm bar
Clamps that were used on the inboard side of the intermediate brackets/bushings
Plastic 21mm Cup rear bar bushings
Size difference between the ends of the 19mm and 21mm bars.
C-clips on the ends of the front 30mm bar
Clamps that were used on the inboard side of the intermediate brackets/bushings
Plastic 21mm Cup rear bar bushings
Size difference between the ends of the 19mm and 21mm bars.
09-05-2010, 08:31 PM
#30
Rennlist Member
Great info ...
I have a dilemma here ...I bought this sway bar from Andial ( on the recommendation of Porsche Motorsports in Germany ( reason being it would be cheaper in the long run as shipping tarrifs etc would be included in the purchase from Germany vs Andial ... Any how ... Here is my issue: My bar doesn't even have the slot required for the E clips ...
What gives??? What bar do I have ? Here is a picture below...
Thanks in advance
Ed