NACA 66 Special A/BGS

[bbarn]

That's a nice paint job on rose rims!!! Even if I do say so myself...

[SPARKY]

Rob what width wheel did you mount these on?

[Jon]

Also, they are very square shoulder design, not like the other MTs and they are about .5 " wider than advertised.

On the brighter side Blue is making great progress on the fuselage body work! You guys should start putting the pressure on him to post the pics.

Bummer about the wheels.
They are very square, are they inflated in the pictures?

Pressure being applied to Blue HERE!!!.

Sounds like we are using similar construction methods, I recently got Mike Arnold's DVDs about his AR-5 plane design and construction.
Interesting viewing for anyone going composite body.

cheers
jon

[robfrey]

Rob what width wheel did you mount these on?

5-1/2" wide

[robfrey]

Jon,
The tires have about 70psi currently. The tire tech had them at 100psi and said that they grew but stayed pretty square.
The AR5 is an impressive piece of work.

[robfrey]

Rob  I will donate my flathead engine for testing [just kiddin]

If we use a flat head, I'm going to steal Buddy W's. That's one bad caddy!

[SPARKY]

The Taylors suggested to me to mount my 26"tires  on  5" rims  made them a Buger to mount  I would bet that you may want to mount them on as narrow a wheel as you can so they will not "pull" away from the rims at speed as they grow.  Pls check with others as I am only repeating one source opinion.

[krusty]

      Rob =  Can you use the Goodyear 21" tire? (15"rim). We run these on the front of the RMR. It will be back at my shop in a few days if you need a mounted width measurement.      vic (your next-door neighbor from Speedweek)

[Interested Observer]

"Hearing rumors that they grow too much  for the clearance we engineered for."

Rob,
Before giving up on the tires you might want to verify the actual growth characteristics rather than relying on "rumor".  From readings on this site, the Burkland's, and possibly others, have facilities to spin them up to LSR speeds.  This could also serve as something of a "proof" test for the tires.

[jl222]

"Hearing rumors that they grow too much  for the clearance we engineered for."

Rob,
Before giving up on the tires you might want to verify the actual growth characteristics rather than relying on "rumor".  From readings on this site, the Burkland's, and possibly others, have facilities to spin them up to LSR speeds.  This could also serve as something of a "proof" test for the tires.

  Read post #394 and put 2 @ 2 together.

            JL222

[robfrey]

      Rob =  Can you use the Goodyear 21" tire? (15"rim). We run these on the front of the RMR. It will be back at my shop in a few days if you need a mounted width measurement.      vic (your next-door neighbor from Speedweek)

Vic,
I would definitely be interested in that dimension and maybe a straight on pic of the shape of the tire. Thank you in advance.

[robfrey]

My theory is: The narrower wheels will have less tendency to have the tire pull away from the bead but will have more tendency for tire growth.
Remember, this car was engineered for 21" dia. 4" wide solid aluminum rollers which do not grow very much at all.
I would really just like to have some rubber up front for some low speed testing.

[Dynoroom]

If it's low speed testing < 250 mph why worry about tire growth?  JMPOV   

[robfrey]

I was not too worried about low speed testing (300 and lower)  tire growth but when these MT became available, I thought I could get away with these for the higher speed stuff without building aluminum rollers. Currently, it does not look like this is possible.

[Glen]

Rob, you need to talk to Rick Vesco on tire growth. teamvescoracing@infowest.com