[QUOTE]Originally posted by inferno camaro:
I am pulling 10 degrees for 1.5 seconds. Tightened front struts trying to keep the frontend down. It wanted to wheelie like crazy. It had some wobble side to side like a boat 1st couple passes. I tightened rear compression and it was good for 3 passes. The last pass it tripped the 330' with the rear tires and wobbled slightly after landing. I think it will be good when I get the front end to stay down more. I just changed from 4.86 gear to 4.56 for this weekend. The lack of tire growth picked me up about 250 rpm out the end so going back to the 4.56. I think with the 4.56 and some more tuning I'll be able to run full timing but time will tell. Lets also not forget track temp was 140+ last weekend also. I love the fact it never shakes the tire. I'm also taking the wheelie bars off for this weekend, hoping removing 35lbs from the rear will also help keep the frond down but hopefully not cause spin. [QUOTE]

Thanks for sharing your info on the PBR, keep us in the loop of getting them dialed in.

2BKING

29.5x10.5 PBRs @18 lbs on my junk. 6.40s at 3090 lbs. I found I needed to loosen my single adjustable AFCO rear shocks to allow the chassis to separate and plant the tires better.

Small burnout with little smoke.

I took it out with the 4.56 gear in it and testing was cut short so didn't get to try much. The car was not happy so I made a 4 link change before eliminations started. The car worked ok, again really high track temps. Once the sun started getting off the track the car was repeating very well. I made 15 passes through the 2 races that day and it had (radial wobble) on 13 of them including the last pass that got so bad it slowed me down .02 and ended my weekend. 60' varied .004 last 4 passes. Was actually pulling more timing than last week 12 degrees for 1.5 seconds just to be sure I could get down. I noticed when changing the 4 link the shocks were damp on top so I pulled them after the weekend and sent them to be rebuilt. Hoping this will resolve the wobble I'm fighting. I still feel these will be really good once everything is dialed in.

Finally didn't rain us out, shocks rebuilt and put back on. Still pulling timing and all it wants to do is rock back and forth side to side. Changed shock settings and tire pressures and zero help. I hate to do it but I think I'm giving up on them unless I can find someone who has some knowledge of what I can change to help with it. Car seems consistent to the 60 then starts rocking/wobbling so never even got to try adding timing back in. Really thought it had potential but I'm out of ideas.

quote:

Originally posted by B KING:
We have been on small radials for about 10+ years. The M/T PBR is our go to radial in a 29.5x10.5 & is a true 30" tall tire with a 10' tread width.

This tire is used on our Camaro at around 3,100 lbs. leaving on a transbrake. They worked great when the car was NA & running high 9s-low 10s. They also work great with our current ProCharged combo running mid 8s 1/4 mile & mid 5s 1/8 mile. We primarily race on hot tracks during the daytime, Las Vegas. We have been a best of 1.27 60' on them.

Any specific questions about them?

2BKING

We finally had to retire our 29.5x10.5 M/T PBR's with 200+ runs. The tread indicators still have a good amount left. I'm pretty sure the sidewalls gave up ship around 175 passes.

We put on our Hoosier Factory Stock 9" radials with about 50 runs on them & won our last of the season points race.

2BKING

quote:

Originally posted by B KING:We finally had to retire our 29.5x10.5 M/T PBR's with 200+ runs. The tread indicators still have a good amount left. I'm pretty sure the sidewalls gave up ship around 175 passes.

We put on our Hoosier Factory Stock 9" radials with about 50 runs on them & won our last of the season points race.

Congrats on your Win!!! Good to hear the Hoosiers worked as good as the prior MT radials. Going from 10.5 to 9” wasn’t an issue?

quote:

Originally posted by markemark:

quote:

Originally posted by B KING:We finally had to retire our 29.5x10.5 M/T PBR's with 200+ runs. The tread indicators still have a good amount left. I'm pretty sure the sidewalls gave up ship around 175 passes.

We put on our Hoosier Factory Stock 9" radials with about 50 runs on them & won our last of the season points race.

Congrats on your Win!!! Good to hear the Hoosiers worked as good as the prior MT radials. Going from 10.5 to 9” wasn’t an issue?

Thanks M & M! No issues, see below.

Here's the inside scope on these 2 radial slicks.

The M/Ts are a true 30" dia. & the tread width measures 10.0". That's me measuring on my rims.

The Hoosiers are made specifically for the 7 sec. Factory Stock shoot out cars. They are also legal in all other Stock Eliminator classes also. These tires are a true 30" dia. The tread width measures 9.9". During earlier in season testing with both tires they were both very close in performance. The tire compound is pretty new for Hoosier & I've only found it on this tire, C30 compound. These are a lightweight radial.

The M/Ts I know can be raced on a shyt surface & be competitive. These new Hoosiers have only been tested on bracket prep.

I have a new set of Factory Stock Hoosiers that are going to be mounted in place of the M/Ts on my double bead locks. They will be my primary tire for testing in colder conditions coming up in Nov. This is where I've had problems (spinning at the hit) back when I started on radials long ago. The fix is a John Force type burnout, lots of heat but still get stopped before the beams.

What I did find out this past weekend with the Hoosiers is they're tire pressure sensitive. I started at 19 lbs. as the rounds got closer together the tire started creeping up. Normally I adjust them down & I did a little, but I let them creep up as high as 19.5. With every .1 of increase the 60' got quicker. I need to revisit going up with more than 19.5 lbs. of pressure.

2BKING

Just for info:

I was dismounting the M/T PBRs today & I could tell the sidewalls were a little too floppy. I guess 200+ runs is too many at this power level.

While I was at it, I weighed the PBRs & the new Hoosier Factory Stock radials. The Hoosiers are 8 lbs. lighter each than the old used up PBRs.

All I have now is two sets of Hoosier Factory Stock radials mounted up. I need to order new pair of M/T PBRs & get another set of matching beadlock rims.

2BKING

quote:

Originally posted by B KING:
Just for info:

I was dismounting the M/T PBRs today & I could tell the sidewalls were a little too floppy. I guess 200+ runs is too many at this power level.

While I was at it, I weighed the PBRs & the new Hoosier Factory Stock radials. The Hoosiers are 8 lbs. lighter each than the old used up PBRs.

All I have now is two sets of Hoosier Factory Stock radials mounted up. I need to order new pair of M/T PBRs & get another set of matching beadlock rims.

I've got a new set of M/T PBRs coming tomorrow. The Hoosier radials beads don't clamp up correctly. My thin beadlock rings, I can't get close to the torque setting & it snaps the heads off the ring bolts. The thicker ring locks don't clamp the beads tight enough & they spin on the rims.

The M/Ts work with the thick beadlock rings. The Hoosiers I'll mount on my non-beadlock rims.

2BKING

quote:

Originally posted by B KING:I've got a new set of M/T PBRs coming tomorrow. The Hoosier radials beads don't clamp up correctly. My thin beadlock rings, I can't get close to the torque setting & it snaps the heads off the ring bolts. The thicker ring locks don't clamp the beads tight enough & they spin on the rims. The M/Ts work with the thick beadlock rings. The Hoosiers I'll mount on my non-beadlock rims.

What brand / style beadlock rims are these? Is it possible to have a ring spacer that fills the gap between the bead and beadlock when bead too thin?

quote:

Originally posted by markemark:

quote:

Originally posted by B KING:I've got a new set of M/T PBRs coming tomorrow. The Hoosier radials beads don't clamp up correctly. My thin beadlock rings, I can't get close to the torque setting & it snaps the heads off the ring bolts. The thicker ring locks don't clamp the beads tight enough & they spin on the rims. The M/Ts work with the thick beadlock rings. The Hoosiers I'll mount on my non-beadlock rims.

What brand / style beadlock rims are these? Is it possible to have a ring spacer that fills the gap between the bead and beadlock when bead too thin?

They're Keizer beadlocks. Mine came with the thin ring locks. When I 1st mounted the M/T PBRs I had the issue of not being able to torque down without snapping the heads off of the fasteners. They sent the me the thicker ring locks & everything was good.

When I mounted the Hoosiers, they were slightly thinner in the bead area. I used the thinner lock rings initially & couldn't get to torque without snapping off the fastener heads. Installed the thicker lock rings but doesn't provide enough clamp force.

The fix would be something in-between the thin & thick lock ring. I see this as a tire manufacturer issue or no standard for the bead thickness.

Below is a lock ring, the portion of the ring with the fastener holes is the area that is thinner or thicker. Sorry, the picture doesn't show the thickness.

quote:

Originally posted by B KING I used the thinner lock rings initially & couldn't get to torque without snapping off the fastener heads. Installed the thicker lock rings but doesn't provide enough clamp force. The fix would be something in-between the thin & thick lock ring. I see this as a tire manufacturer issue or no standard for the bead thickness.

What’s the torque spec?

quote:

Originally posted by markemark:
What’s the torque spec?

18 ft lbs.

Not being smart. Maybe saw off a portion of the bead from a Hoosier and MT and send it to them to show what you’re dealing with.

Are the fasteners bottoming out? Almost have to be to snap them off.

quote:

Originally posted by Goob:
Are the fasteners bottoming out? Almost have to be to snap them off.

They aren't blind holes. You have to take up the gap between the ring lock & the wheel flange. If the gap is too much the head of the bolt takes all the load. Plus, I'm using titanium fasteners & I'm pretty careful. I torque in 2 steps & a crisscross pattern.

I hope to take some better pics to show the procedure.

2BKING

quote:

Originally posted by markemark:
Not being smart. Maybe saw off a portion of the bead from a Hoosier and MT and send it to them to show what you’re dealing with.

M & M,

I'm not going to bother with it. I know Keiser states the bead thickness is different between tire brands & even different in the same brand depending on the type of tire.

I'll set-up the M/T PBRs on the beadlocks & have the right lock rings for it. The M/Ts are directional & don't want tire to wheel slip.

As for the Hoosiers/back-up radials. I'll mount them on standard rims.

The nice thing is Hoosier radials are non-directional. I can move them side to side to take care of the tire to wheel slip.

2BKING

quote:

Originally posted by B KING:

quote:

Originally posted by Goob:
Are the fasteners bottoming out? Almost have to be to snap them off.

They aren't blind holes. You have to take up the gap between the ring lock & the wheel flange. If the gap is too much the head of the bolt takes all the load. Plus, I'm using titanium fasteners & I'm pretty careful. I torque in 2 steps & a crisscross pattern.

I hope to take some better pics to show the procedure.

2BKING

Ahhh, gotcha! That makes sense.