63 replies to this topic

[Michele Bilancia]

Here are some more photo...
No, I don't have the body...
What about the guide, the wheels and the gear? Are those period correct or not?

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[MSwiss]

Everything looks fine except for the red tires.

In that era, just about everything was orange.

Jim H can comment/confirm on that.

If you put a body on it, an O/S Ferrari would be ideal.

[Michele Bilancia]

So also the motor is late 70s? The armature inside is marked x12. Also that one is correct for late 70s?

[jimht]

As Mike S said, except for the red tires., if they are red?..and they look like full hub so that's later.

 

And the guide also might be later date than early Eighties, I'm not sure if the nose should be angle cut...Starburst?

But, who knows what they were doing in Italy, slot racing everywhere...

 

Regardless, nice.

[MSwiss]

So also the motor is late 70s? The armature inside is marked x12. Also that one is correct for late 70s?

I don't know exactly when Mura introduced that can.

 

I'm pretty sure it was around when I got back in, in late '81.

 

But I also already explained that particular motor is from the late 80's, based on it's paint job.

 

Regardless, X-12 arms never gained popularity until long after that chassis was made.

 

Jim H might remember if X-12's was a "thing", at all, around 1980.

[MSwiss]

As Mike S said, except for the red tires., if they are red?..and they look like full hub so that's later.

 

And the guide also might be later date than early Eighties, I'm not sure if the nose should be angle cut...Starburst?

But, who knows what they were doing in Italy, slot racing everywhere...

 

Regardless, nice.

Good catch on the full hub.

 

Someone probably had, or got a hold of that car in the late 80's, early 90's, and installed that motor and tires.

[jimht]

That's the Mura MPP can, also referred to as the "Trinity" can, I vaguely recall, maybe?

 

So it appeared when Ernie Provetti was racing????  So late Seventies or am I remembering things out of order?

 

Don't even ask me when Outlaw 12 became X12. LOL

[Bill from NH]

Ernie was racing in the early '70s, '70 & '71. He came up to the monthly CT races at Coventry & Forestville with Tony P., Fred "Da Flash", & "Pumpkin Man" Tom Lowrey as part of Team Tony P..

[Michele Bilancia]

I made a research on the internet for the Mura Trinity Can. I think you are right, the holes pattern is from a Trinity can, that should be a Group12 motor. I discovered that this type of can should be beginning of the 80s. So, would you leave that can? Or would replace it with a older one?

[Bill from NH]

There were red tires in the early '70s. I believe they were Associated that I saw at Modelville Hobby-Framingham. They came in red, gray, orange, & black rubber. No argument that during this period orange was the most popular with blues a distant second. 

[Mr. M]

From the bottom, the center looks hand cut, not a production piece.

[MSwiss]

I'm 98% sure it's the Parma, with the slots hand cut.

[Bill Seitz]

Jim Honeycut was building chassis like these, so I'll leave it to him whether this one is custom or a modified production piece. This general design of steel center section with pans and axle tube was a common style in US racing around 1980 give or take a few years. I'm familiar with variants of the basic design depending on who was making them. They were legal for G27 and G7, so an X12 is not correct for this chassis in US racing. It's a C-can chassis, and I believe cobalt "strap" motors and pillow blocks took over completely by 1985. The Faas gear is period correct, and the front wheels and guide might be. Full hub rear wheels were not around at the time of the chassis, although there were red tires.

 

A period correct Mura motor would have had a yellowish colored endbell and used buttonhead screws to attach the endbell hardware which included brass spring post cups. The sockethead cap screws are a user modification using the heads of the screws for spring posts eliminating the Mura brass spring post cups. Other color endbells came later. I have purchased some black can Mura motors with purple endbells, probably late 80's/early 90's.

 

Best I remember the original Mura "12" was a low-cost economy motor for entry-level Ready-to-Run cars in the mid-80's. The first I recall is the Parma Brasskar. The arm wasn't balanced, and there was some variability in how fast they were which was troublesome in the new racing classes that were created for them. The Outlaw 12 or X12 as it became known came later as a balanced arm with more consistent performance. The "12" motor didn't exist during the period that this style chassis was popular in the US. X12 is a late 80's motor.

 

The Mura motors before 1990 had .630 long magnets. I've had Mura X12 arms that varied in stack length from about .400" down to .370", so the armature stack will appear quite shorter than the magnets. I believe the longer stacks are the earlier versions and the stacks became shorter as production progressed and rules (like USRA) set the minimum length at .360 (now .350 same as the Wasp arm). I only owned one Mura G7 arm that's long gone, but the G27 and G20 arms I have use stacks from near .500" long (.495) down to .460". The USRA rules specified .440" as minimum length, but I've not seen Mura arms this short. Again, I believe earlier armatures had longer stacks.

 

Unless you're trying to create a period correct collectible, I'd take this car and enjoy running it. The X12 motor will be much tamer and easier for most people to drive than the period correct G27 or G7 motor. It'll be a fun car to drive that does still mostly represent a bygone era when we still raced scratchbuilt wing cars.

[jimht]

Bill Seitz has covered it and all I'll add is that the only way we could get these tanks to go around wih Open armatures was to use copious amounts of brown glue...frequently.

 

A good running Gp12 would be enjoyable, anything more would be impressive but not probably not much faster even with glue.

[Michele Bilancia]

Guys, thank you very much for all the very useful info.... Appreciate a lot your effort!

[Mark Onofri]

Mike, are you referring to the Parma chassis or the one in question?
I was thinking the same thing about the plating. When New Process Gear was in Syracuse, almost anything was possible.
I'll find a copy of the 80's pro cars. Everyone can come to their own conclusion.
MORE PICTURES please!
Let's not rule out a European production chassis.

[Mark Onofri]

Oh, I was on the wrong page,. Thanks for the pictures.
Jimht, although at the time I was lacking it driving skills, they were a handful with G-20's. Well, for me anyway. I guess some things never change. Can't imagine a open class version but, it's on my list. I just find this style of car , well, my favorite.
Now if I can only find that article. I'll be back.

[Michele Bilancia]

Last question from my side... On the bottom of the side pans I see some very thin white plastic. Do I need to peel it off? Or it has to remain there?

[Mark Onofri]

In the early 80's, steel centre sections with brass pans were popular. By the mid 80,'s, the split pans came into favor. Just before the tri-pods, the front pans were also split. A small section attached to the plumber rail & the front wheels attached to the outer section. This narrows the time period down or, it's a holdover.

[Bill Seitz]

To answer Michele's question about tape (white thin plastic) on the bottom of the side pans, this would be period correct. Pans are known to droop, or tires compress, under high-g, high downforce loads (going around a banked turn at high speed, for example), and the pans could touch the track braid with quite spectacular display of sparks. Plastic tape on the pans prevents this.

 

I've owned a couple dozen of these old Mura's over the years, and the endbells tend to get stripped threads and have the spring post bosses shear off. A larger 2-56 x 1/4" sockethead screw makes a serviceable repair when this happens. It ends up looking like the endbell hardware in the above photos.

 

As Jim has mentioned, a chassis like this with a G7 or even a G27 motor will be a handful for some people to drive on anything other than maybe a King track. Modern tires would help, though. I'm impressed by how much more grip the current natural rubber and wonder tires have over those old SBR foam tires. For a car I was going to run on the track, I'd switch to modern tires and keep the X12. I think Michele might want to make a period correct display car, so in that case, I understand why he would like to have the correct motor.

 

The last of the side pan chassis had cutout pans, and anything as late as mid-80's would have had cutouts. The full pans make this an earlier chassis, probably not later than early 80's. 

[Michele Bilancia]

Finally I get the opportunity to speak with one of the old owners of this chassis. I discovered it participated to Italian Championship in 1978/9, in a "open" class. And also I got confirmation that the motor has been replaced in beginning of 90s. So I think that all what Bill guessed is correct... Now I will try to rebuild the chassis as period correct... Anybody has photo for a correct body? Should be a late 70s wing car. I'm also searching for a late 70s G7 motor, for the gear and for the wheels.... Thanks to anybody who may help!

[Mark Onofri]

Bella! I was close! If and when I find the article, it has a very detailed account of the motors. The last of the C- cans. For the U.S. anyway. It might be different there. Andiamo en gato!

[MSwiss]

I miss those Slick-7 beryllium uprights!
Earlier than the 90's . Jahn L. Won the nats 3 years running 84-86(?) Running similar chassis's. By 87-88 (?) EDM had taken over. Mike S, you probably know better than me. I know Philippe wrote a article about this. I made several copies so I could lose more than one.

The Slick 7 beryllium uprights, and ones like them, were created so pillow blocks could come to I15 racing, as flat steel pieces weren't allowed  beyond 1.5"(?) of the guide centerline.
 
If "Jahn L." is referring to to Jon Laster, he won his only G7 Nat's championship in 1992, at Zeppelin Hobbies.
 
1984 was the last year a conventional(non-perimeter chassis) won the Nat's.
 
Csaba S. was the winner with a lightweight car that spawned a similar center section from Slick 7.
 
His success with lightweight cars made Stu Koford and myself start thinking of alternative lightweight cars.
 
I had already been running perimeter chassis, but with somewhat heavy internal pans.
 
We both decided that my perimeter cars, but with a lighter body mounting system, might be the ticket.
 
Stu tried talking me out of one of my existing cars, to cannibalize, for the center.
 
I declined because I didn't think it would work(the center was only 3" wide) with what he wanted to do plus it had a bit of sentimental value from using to win Semi-Pro at the Midwest Nat's, in my first G7 race.
 
He wound up hand cutting his own center and using solid body mounts.
 
In it's first race, a weekly at Broadway Raceway, Stu broke the existing world record of 2.68 with a 2.62, only to be cut later that night, by Csaba, with an even lighter conventional style car, with Csaba going an incredible 2.51.
 
Csaba's 2.51, and Stu's lack of success in the race, had Csaba labeling the perimeter design as qualifying OK, but would never be a good race car.
 
I finished up my latest design a week later, which used rectangles and full width bars floating inside, to provide similar movement of conventional cars.
 
My car raced real well, and when I broke the G27 qualifying World Record, at Grand Raceway, Csaba took notice.
 
He built his own perimeter car for the next points race, but entered it with tape covering the bottom to prevent the tech inspector from seeing the design.
 
After one lap, he stopped and removed the tape and broke his 2.51, with the first car in the 2.4's, with a 2.49.
 
When I then broke the 2.49, at the next race, with a 2.47, it started the demise of the conventional car.
 
Henry Pena won the 85 Nat's with a perimeter chassis, with perimeter chassis filling the Main.
 
In that same 85-86 era Tom Hansen broke the World Record a few times with his tripod design, and Paul Stafford, of the Detroit area won G27 at the 86 Nat's at Andy Smith's ( now owner of Professor Motor) raceway.
 
As far as EDM cut chassis, some low volume pieces were cut in approx. '82-'83.
 
In 1985 when the perimeter design got popular, Mike Kolar, a Denver area racer, designed the GTO, and EDM cut it at the machine shop he worked at.
 
Shortly after that, Camen, Slick 7 and Koford all purchased their own EDM machines.
 
Before that, they had their various designs, acid etched by outside vendors.


My '83 and '84 heavy and light perimeter chassis.

[Mark Onofri]

Mr.M, there were yellow,red , white and ,blue dot magnets by Champion. The reds were longer than the whites. I don't remember seeing the yellow out side of a motor . I'm pretty sure the blue were in short supply or discontinued by the 80's. I recently

[Mark Onofri]

Stupid phone, I recently acquired a set of blue dots. I would not have even known about them if it wasn't for dc-65x.