New Drag Radial Tire Rub. HELP!

[Hognose]

I just bought and had on my new BFG 275/50/15 DRag Radials. I have T-Type rims on my GN. As I was coming home and taking turns I notied they were rubbing. When I got home I can see where on the frame they are rubbing. I thought that I read that this tire on the T rim wouldn't rub. Is there a spacer I can put on that will prevent this? Or is there some other solution orther than new tires or rims? Thanks,
Matthew

 

[pacecarta]

every car is different , some axles arent centered

fresh bushings, 6in the controll arms and 2 in the axle ears to minimize axle wander , or some longer wheel studs and some spacers, if theres more space on one side and the bushings dont fix it you want to consider adjustable uppers to locate the axle.

if its rubbing low on the frame in the rear ,maybe try fresh springs or air bags to raise the frame
and an 8 or 9 in rim will have less bulge at the rear and more room with the same backspace

 

[Hognose]

It is rubbing low on the frame. On the drivers side it rubbing just at the front of the tire and on the back as well. On the pass side it is only rubbing on on the back.

I do have air bags in the car. I have no idea what they are set at. I didn't realize that they were in there until last weekend, when I was changing my rear diff fluid. I did feel what the pass side had more pressure than the drivers. So, I guess I could try pumping them both up. What is the max pressure they can hold?

Thnaks for your help
Matthew

 

[pacecarta]

35lbs is what the sticker says is max , 5lbs minimum

i wouldnt run them at 35 youll find it goes pretty high at 17

at the track you will have to play with the pressure to see what you need to launch with, hopefully they are run seperately so you can adjust the pressure to each bag , try 18-20 pass and 5-11 in driver

also, what pressure did you run in the DR's?

 

[Hognose]

Yes they are run separately. I am not sure what theyt set the tires at. I would gues about 32-35. I know that I would need to lower them for the track. What should they be on the street?

That would be easy enough to re-adjust the airbags when going to the track.

Would new springs hurt in the launching dept?

Thanks for your help.

Matthew

 

[pacecarta]

once you get your tires to not rub put down some marks and get out and look at them ,
and adjust tire pressure till they are dark all the way across the thread width and as wide as the tread , if they are thin , lower the air in the tires , if they are darker on the sides add air to the tires
use the airbags to even out the darkness from side to side and to try to make them them the same length

 

[UNGN]

Originally posted by Hognose
I I thought that I read that this tire on the T rim wouldn't rub.

You didn't read that in any of my posts. I've always said the 50's will rub the frame on offramps (going on 7 years now). They shouldn't rub in a straight line, however.

I also would not have gone 50's with your combo. With a non lockup converter your car will be quicker with 275/60's. They even rub less than the 50's, too.

 

[Quick6'n'-K.C.]

Switching to Aluminum drums will give you 1/4 of an inch space away from the frame if you dont have them already.

there is more meat on the surface of the drum where the axle studs stick through.

HTH

BW

 

[Hognose]

Originally posted by Quick6'n'-K.C.
Switching to Aluminum drums will give you 1/4 of an inch space away from the frame if you dont have them already.

there is more meat on the surface of the drum where the axle studs stick through.

HTH

BW

Thank you, that is a good idea. However until I find a set of Aluminum drums, a 1/4 spacer should work correct?

Thanks again.

Matthew

 

[Quick6'n'-K.C.]

yes

and the aluminum drums can be found at the junk yard on most 82-92 V8 f-bodies

BW