Bill - those are the arms Mumzer was making sometime ago. The Racers Edges units are square tubing based.

 

I think there was some background story as to where Mumzer got the original design - and it may have come from one of the shops/teams that were running in the Rothmans Turbo Cup series in Canada. But those are not factory motorsport arms.

Very trick, I wish they were still made.

 

Those arms could easily be reproduced if one could get their hands on one.

 

Were do you purchase the replacement ball joint for the Racers Edge arms? Anyone have a picture that shows the ball joint mounted to the arm?

 

I have two. One right, one left. Sitting under my work bench. Never been installed. When I can round up a set of TS spindles, I plan to install.

SKIP, Yes Mumser arms.

ODDJOB, Factory designed the arms. Sent cad file to Dealer on east coast for manufacture. East Coast Dealer charged with maintaining parts for the Canadian Turbo Cup series. Arm design came late in the series, so I do not know if any were actually installed before the series demise. Dealer long gone. Mumser secured cad file. I believe Mumser made three sets. One for himself, my set and a set he sold to someone back east. The set back east was destroyed during a hard anodising process, done incorrectly by a plater. After some stink by the guy back east, Mumser refunded money. Guy sent back arms and bought Charlie arms. Mumser cut up the east coast arms for failure anlysis. Mumser decided he did not need the grief. Mumser long gone. Agree, very trick part.

 

Hmmm - unfortunately that's not quite how the story went, but not worth dragging up it up again.

 

The dealer in charge of the handling motorsports parts for the Canadian/Rothmans Series was:

Porsche Division
Volkswagon Canada Inc
1940 Eglinton Ave. East
Scarborough Ontario

Not sure that is still a current address, but I would guess that Porsche/Audi/VW still exists in Canada. But pretty sure that CAD files didnt exist in the late 80's.

I had to check my memory, so searched back and from mumzers old thread that Skip doesnt want dragged up again.... " the arm has existed for a number of years, but hasnt been built in quantity ever. It was initially produced by a race shop back east during the firehawk days, and my partner and I have been negotiating to resurrect the things..."

Not sure of which Firehawk team he would be referring to. Kelly Moss is in WI. Not sure where Team Matthew was or where Mark Sandridge Team Salad was based. What was the other team, Dave White (?), thought they were from down south.

But again, Bill, not trying to take anything away from you or those arms. They look to me like they might be one of the best designs out there.

I personally am not a big fan of using either the Charlie Arms, or the Racers Edge arms because I do not want to machine the front spindles for the larger 19mm ball joint pin (I think it weakens a weak point on the spindle - the pinch bolt area). That is the one feature about the Fabcar arms that I do like, the 17mm pins. I recall the mumzer arms either used a 17mm pin or had a choice? Which size pin do you have?

I have done some looking into manufacturing a similar type arm, with a target price less than what the other aftermarket arms are going for, maybe something around $1000-1200 for the set. It can probably be done, but I have not thought much past the concern of liability. Not sure its worth accepting the risk of making a suspension component, to replace a part known for catastrophic failure, for cars that will be raced. I understand why mumzer dropped the project, and his problem occurred before the parts were even installed....

 

early offset arms:
http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMESE%3AIT

 

Oddjob,

Interesting stuff. The story I quoted, was the story Mumser told me when I bought the arms from him. Mumser said he bought the cad file from the machinist the east coast dealership used for fabrication. Mumser said the dealership stiffed the machinist for some money when they went out of business. Since I was not directly involved with the history of the arms, I do not know which story is true. Were you involved with the Turbo Cup Series? Jon Milledge was the key guy for the Carlsen Firehawk 951, perhaps he is aware of the arms.

Dont know off hand what the pin size is on my arms. I can measure tonight.

I have been contacted by a lister that says he can scan the arms and create a cad file, and then produce the arms. I am not sure what I think of this idea. I would be concerned about shipping my arms to someone I do not know anything about.

 

Jon Milledge was involved with the design of the Charlie arms. When I originally read that these arms came from the firehawk series I thought it was odd - because why would Jon then be involved with designing a completely different arm. Didn't like them? Didn't know about them? Didn't have the rights to them? They didn't exist? I don't know.

--bmorris
89 951

 

The Mumzer arms have 17 mm pins.

Someone has since bought the rights to that design and could possibly start manufacturing them again, so I'd be a bit careful about lending the arms to a Lister to copy and mass produce, as you would be stepping on the toes of the current owner of the design.

 

Bill,

No, I had no personal involvement in the Turbo Cup series. I have copies of some of the Canadian/Rothman's series documentation, including part lists and a cover letter to the race teams that instructs them how and from whom to order the unique motorsports parts.

Carlsen is out of California. Milledge was a driver for the winning IMSA Firestone Firehawk 944 n/a in '85, and then drove a 944 Turbo Club Sport for the Carlsen team in the '86 SCCA Escort Endurance Championship. Carlsen did not run in the Series in '87, so I dont think John would have been involved with designing a late offset a-arm upgrade at that point. And I dont know if he had any involvement with the later years of the Firehawk Series, when the S2s were running.

Sounds like there is quite a bit of folklore associated with the "mumzer" arms. But again, regardless of the actual history or source of the design, they are pretty trick.

 

Folklore aside send them to Oddjob and I, we'll get them made. I have a 3 axis machine just waiting for something like this.