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Need help and info on Class 12 Car

CZLou

Well-Known Member
From what i have read. It seems eveyone is running Super Diggers 3 on the rear. What rim width and tire pressure is being run on these? I've seen 4in. to 7in. rims being used. What is the idea on the different rim width? Hard pack, soft sand or ?
 

jsallenbach

Well-Known Member
We run on both cars 4 inch wide rims, brings the side walls in so it makes them less vulnerable to getting flats there. Tire pressure we would run with the supper diggers 32 psi and had hardly any flats.
 

CZLou

Well-Known Member
With 4in. rims, Wouldn't that leave less of a foot print = Less traction in a straight line and more slip in a turn? what am i missing here?
 

RaptorLou

Well-Known Member
I concur on the narrow rim (4-5) for protecting side wall and 32 PSI is what I ran, less flats. Digger 3's are soft, so don't expect much left at end of race.
 

RaptorLou

Well-Known Member
less rolling resistance at speed (contact patch) and acts like a baloon tire in the sand.....
 

CZLou

Well-Known Member
Yes they are. We went thru 2 sets at lasts years NORRA 1000. I couldn't believe how fast they wore out. We ran a centerline 6in. rim with 28psi. Is there any other tire out there to run. That stands out or are Diggers3 about it?
 
I would run the yokohamas on a 15x4 just to make it a little taller then running on 15x7s.good tire. I started running the bfg Baja ta and have not had a flat in 4 races.
 

Rory

Crayola Killer
You will get all kinds of opinions on tires. I've pretty much always been a BFG guy starting back in the late 80's. I have had nothing but good luck with them weather it was on my old 4 seater, TT Killer, prerunner or the class 12 car.

For the limited classes, most believe to be competitive, yokohama's are the way to go due to how light they are. I was told that you could only get about 200 miles out of them if you were a front runner. You can be competitive with BFG's too but most guys have to shave 1/2 the tread off the tire for weight purposes, hard to pull the sand washes in 4th gear (1600-5/1600).

Last year I ran the Mickey Thompson MTZ's and Baja Claws on Challenger IV at NORRA and was VERY impressed with the performance. It would be interesting to see how good they could be if they were to throw a little money into the production of a true off road racing tire like the BFG project.

Speaking of BFG again, they have a new class 10 project tire that is similar to the thread for the TT Project. It's a 35x10.50x15 race tire that only weighs 48 lbs, the 33" Baja TA (popular class 10 tire) weighs 54 lbs!

Be nice to see another tire war like they had back in the late 80's, they were throwing tires at EVERYONE!!! LOL.
 

CZLou

Well-Known Member
I'm looking at the BFG mud terrain 33x12.50r 15 for NORRA. Is this the BFG that they shave 1/2 the tread off? What are your thoughts on them? I just can't get over the Yokohama's being bald by the time we get to Loreto.
 
I think the 12.5 is too wide for for a 12 car. You would have to run a 7 inch wide wheel. On our old 12 car we ran the 33x10.5x15 bfg mud terrain which we shaved and it worked well for us.
 
On the front we used to run the bfg all terrain 33x9.50x15 which was a good tire as well. I think I still have 2-3 of them which I'm planning to sell here pretty soon. Fyi
 

CZLou

Well-Known Member
Sounds good. I plan on running some PRT / ARCO rim's 15x4 frt. 15x7 rear. Have you heard anything about them? How are the side walls on the All terrains for the front?
 

frostbite36

Capt. Hindsight
15x4 front and rear rims to save reciprocating weight versus wider rims, plus the tire profile is a little taller with smaller width rims which helps a little in big silt beds or deeply burned in tracks. I always run bead-locks on the rear so if I get a rear flat I don't lose the flat tire off the rim if I have to drive any distance while flat or spin the rim inside the tire and get stuck in a track while driving over a berm to find a place to safely change the flat. I like the 33x9.0x15R Mickey Thompson Baja Pro Rear tires as they last much longer than Yokohama Super Digger IIIs, but free tires are the best tires.

BFG Projects are super tough, but a little heavier. If you have to buy them, they are kinda expensive too. DOT BFG All-Terrains totally suck...side walls are too thin for racing.

Jimco Racing can certainly build you a bad-a$$ buggy. They just built Jason Coleman's class-10 car and he then proceeded to get 2nd at V2R on its first outing.
 
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frostbite36

Capt. Hindsight
Contact the tire reps who attend the races to at least get discounted tires. Free tires come with race success and after building relationships with the race tire suppliers and/or sponsors.
 

burninfuel

Well-Known Member
Well if you run the mickey Thomsons for the front, there heavy but same tire has had 3 rims replaced and tire is still good ????? red team 1029 vorra 2000 to 2010 +
 

frostbite36

Capt. Hindsight
I forgot to mention I don't run the 33" Baja Pros in the front, though. I run Akuret Cargo Highway
7.00-15 E/, 10 ply trailer tires up front.
 
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