Show full size 924Board.org
Discussion Forum of 924.org
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to 924.org924.org   Jump to PCA 924 Registry924 Registry

Monoballs vs. OEM rubber?
Goto page 1, 2  Next
 
Post new topic   Reply to topic    924Board.org Forum Index -> Performance Upgrades
View previous topic :: View next topic  
Author Message
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Sun Jan 07, 2007 12:36 am    Post subject: Monoballs vs. OEM rubber? Reply with quote

Redoing the entire brake and suspension on my 931 track car. I am up to the rear trailing arm bushings and I am unsure of whether to go with monoballs or OEM rubber. Monoballs are $300 and OEM rubber is $100.
Any thoughts from the track guys/girls who have used the monoballs or who have replaced the old rubber with new rubber?
I have read that the monoballs allow better camber set up for the rear wheels as opposed to the OEM rubber. Don’t know if this is true.
Rest of the suspension is polyurethane properly installed with grease fittings.
Shocks/springs will be coilover fronts (probably 400lb springs) & 30mm T-bars, with custom valved shocks.
Lastly, can anyone recommend from their own experience a good replacement for the Spring Plate Cover rear mounts? These mounts attach the outside ends of the torsion tube –the part that looks like a leaf spring- to the chassis.
Thanks in advance.
Back to top
View user's profile Send private message
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Mon Jan 08, 2007 6:44 am    Post subject: Reply with quote

Sort of answers my question:
http://forums.pelicanparts.com/showthread.php?s=bc4b60669344b5c902f64d05d20f4e2c&threadid=320511&highlight=trailing+arms+monoballs
http://forums.pelicanparts.com/showthread.php?s=bc4b60669344b5c902f64d05d20f4e2c&threadid=305329&highlight=trailing+arms+monoballs
http://forums.pelicanparts.com/showthread.php?s=bc4b60669344b5c902f64d05d20f4e2c&threadid=276749&perpage=20&highlight=trailing%20arms%20monoballs&pagenumber=1
Conclusion: either Monoballs (elephant racing have better seals) or OEM rubber, but not Poly for the rear trailing arms.

Now, anyone going with solid Spring Plate Cover rear mounts?
Back to top
View user's profile Send private message
924guy  



Joined: 29 Dec 2003
Posts: 2088
Location: Port St. Lucie, FL

PostPosted: Mon Jan 08, 2007 11:51 pm    Post subject: Reply with quote

watch your clearance if you go with monoball... on some 931's it can be an issue iirc... I went with rubber, but im also (re)building with mostly street duty in mind, though it is impressive the difference that it made just with adj koni's and new oem rubber mounts (the old ones came out in several pieces.)
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha
Back to top
View user's profile Send private message Visit poster's website
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Tue Jan 09, 2007 1:24 pm    Post subject: Reply with quote

Eric,
I haven't heard of mounting problems, but I have heard of what a PITA it is to remove old stock trailing arm bushings. However, my trailing arms are already stripped, expoxy primed, and awaiting monoballs and new bearings/seals/ect.
As for OEM rubber, I am a big fan: best bang for your buck and works great on the track. My 924 has been tracked since 98' and I always had a lot of fun, especially with all the body sway with the OLD stock suspension
For the 931, I am going with a full track suspension.
Back to top
View user's profile Send private message
simsport  



Joined: 06 Nov 2002
Posts: 573
Location: UK Warrington

PostPosted: Thu Jan 11, 2007 4:39 am    Post subject: Not Sure Reply with quote

I'm not sure the people on the link are correct about the poly rear bushes. I have had them for years on my car and it handles very well on track.
The idea that the original rubber bush has to give a little to allow camber adjustment doesnt sound right to me. The race cars had the inner end of the arm on a shim arrangement and it was the lifting or lowering of the inside that created more or less camber. On the normal road car its achieved via the spring plate which has the same effect but also gives a chanage in rear toe angle.....which is why its less good for a race car....could be wrong on this of course and open to other views as ever!

Cheers
Simon
_________________
Blown is always best!
Back to top
View user's profile Send private message Send e-mail
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Sun Jan 14, 2007 5:16 am    Post subject: Reply with quote

Simon,
You are using poly for the rear trailing arms? I could not find them for the 924/944 series, only for the 911. Can you post the part # and a link to the ones you are using.
Also, I assume they are working fine for you.
BTW, I still have the european magazine which did a feature of your car -- along time ago. Nice job.
Back to top
View user's profile Send private message
simsport  



Joined: 06 Nov 2002
Posts: 573
Location: UK Warrington

PostPosted: Sun Jan 14, 2007 8:35 am    Post subject: Peter Reply with quote

Hi Peter.
You can find them listed at AUTOMOTION.COM

Yep, they work fine, they are hard and do creak a little but the car tracks true.

Cheers
Simon
PS Which mag?
_________________
Blown is always best!
Back to top
View user's profile Send private message Send e-mail
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Sun Jan 14, 2007 12:30 pm    Post subject: Reply with quote

Hi Simon,
I went the Automotion site, and they don’t seem to carry them anymore for the 924/944.
http://www.automotion.com/productpage.aspx?pid=110315&name=Weltmeister%c2%ae+Rear+Race+Bushings#anchorLink
They show a diagram, but that is for the 911.
An internet search revealed 911 trailing arm bushings, but no 924/944
http://www.pwr-tech.com/parts_suspension.html (scroll to the bottom of the page, they are number 5 in the diagram).
By any chance, did you buy 911 rear trailing arm bushings? I am sure some year will fit, but do you know which one?
Pelican carries both the OEM rubber and monoball rear trailing arm bushings, but only poly for the 911. http://www.pelicanparts.com/catalog/shopcart/944M/POR_944M_SUSshk_pg5.htm
Weird.

The article about your car was/is in the April 2002 issue of 911 & Porsche World. Looking over the pictures in the article, “Swiss Cheese” comes to mind. You sure like your hole saw.
Thanks,
Peter
Back to top
View user's profile Send private message
Rasta Monsta  



Joined: 12 Jul 2006
Posts: 11378
Location: PacNW

PostPosted: Sun Jan 14, 2007 1:26 pm    Post subject: Reply with quote

They still show on the Weltmeister site, they must be somewhere.

EDIT - Here are some at Paragon.
_________________
Toofah King Bad

  • Red (1987 924S) - Pro44/Spec944
Back to top
View user's profile Send private message Visit poster's website
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Mon Jan 15, 2007 4:15 am    Post subject: Reply with quote

Rasta Monsta wrote:
They still show on the Weltmeister site, they must be somewhere.

EDIT - Here are some at Paragon.


Thanks, but we are referring to the rear trailing arm bushings (which only seem to be available in either OEM rubber or Monoballs). You are referring to either or both the spring plate and torsion tube mount bushings. Different things.
Back to top
View user's profile Send private message
Smoothie  



Joined: 01 Jan 2003
Posts: 8030
Location: DE (the one near MD, PA, NJ)

PostPosted: Mon Jan 15, 2007 5:36 am    Post subject: Reply with quote

I have an old printed Automotion catalog from 1996. Under Weltmeister poly-graphite suspension bushings, it's showing everything but those specific bushings you're looking for, for the 924-944-968. The same bushings for the 911-912 rear "banana arm" as they call it, do appear in that catalog. -So I'd suspect they were never available for 924-944-968 either from Weltmeister or through Automotion.

I don't know if it's do-able, but if the opening that accepts the bushings in both the 911 and 924 rear arms happen to be the same (would need verification) and you don't mind redrilling the mounts on the torsion bar carrier to 14mm, then you might be able to use the 911 poly bushings.. ?
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox
Back to top
View user's profile Send private message Visit poster's website
Peter  



Joined: 04 Nov 2002
Posts: 379
Location: New York, NY

PostPosted: Mon Jan 15, 2007 9:31 am    Post subject: Reply with quote

I couldn't find them either Smoothie, that's why I asked Simon for a link.
I am just going to go with Monoballs.
Back to top
View user's profile Send private message
simsport  



Joined: 06 Nov 2002
Posts: 573
Location: UK Warrington

PostPosted: Mon Jan 15, 2007 10:01 am    Post subject: Bushes Reply with quote

Peter
Not sure why they might be dropped, all I can say is mine has them.
I suppose they could be a 911 part number?

I ordered them through my friend at 9M racing in warrington some years ago now, in fact prob about 6 or 7 years ago !

That alone should indicate how hard they are , and in a sprint car run about 12 times a year how long lasting.

Another option is to ask POWERFLEX here in the uk if they will make a set for you. As I remember there is nothing too clever about the deisgn of any of the original rubber bushes.

Yeah it did have a lot of holes in those days. Its better looking now with fewer holes and lighter body parts, plus about 40bhp more!

Cheers
Simon
_________________
Blown is always best!
Back to top
View user's profile Send private message Send e-mail
924RACR  



Joined: 29 Jul 2001
Posts: 8325
Location: Royal Oak, MI, USA

PostPosted: Tue Jan 16, 2007 1:15 am    Post subject: Reply with quote

I upgraded from the stock old rubber to monoball some years back, very happy with the results. I'm using the Racer's Edge parts. They're so nice, wish I was using them up front too.
_________________
Vaughan Scott
Webmeister
'79 924 #77 ITB racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype
Back to top
View user's profile Send private message Send e-mail Visit poster's website
John Brown  



Joined: 07 Nov 2002
Posts: 903
Location: Leesburg VA

PostPosted: Tue Jan 16, 2007 11:03 pm    Post subject: Reply with quote

You are, I think, correct in that the only thing for the inner trailing arm is OEM or monoball.

The popular 'cost effective' setup right now is delrin and poly everywhere, except the inner trailinig which most just leave OEM. You are also correct that the inner trailing is where there needs to be some twist to accomodate camber. An elongated inner bolt hole will also allow enough slop to get more camber. Cheaper than monoball.

Only know of a couple cars with the Elephant. Seems to work very well; time will tell how durable they are.
_________________
John
80 931 - #931 44Cup
99 Escalade - tows track cars
gone but not forgotten: original 924.org car - 82
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    924Board.org Forum Index -> Performance Upgrades All times are GMT + 10 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group