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FE Power Forums => FE Technical Forum => Topic started by: GJCAT427 on April 18, 2016, 05:14:36 AM

Title: tire screws on slicks
Post by: GJCAT427 on April 18, 2016, 05:14:36 AM
How important would screws be on a set of 9x15 aluimium slicks on aluinium wheels? Car is a 63 galaxie with 427, 2x4, stock "AA" cam, 9" with Detriot locker, toploader & traction bars. I`ve got a week before Beaver Springs to put them in if needed. Oh yah slicks have tubes in them.
Title: Re: tire screws on slicks
Post by: fastback 427 on April 18, 2016, 06:52:00 AM
We don't put screws in ours anymore, just put a small layer of "hi-tack" aviation sealer on the bead.  Never had them slip yet.
Title: Re: tire screws on slicks
Post by: jayb on April 18, 2016, 07:37:58 AM
If you've got tubes I'd be a little concerned without the screws.  If the tires move at all on the bead they can shear the valve stem off the tube.  JMO, but I'd put in the screws...
Title: Re: tire screws on slicks
Post by: fekbmax on April 18, 2016, 08:03:19 AM
+ 1 with screws and tubes. Especially if your running less than 12psi.
Title: Re: tire screws on slicks
Post by: rcodecj on April 18, 2016, 08:21:12 AM
+2 on screws with inner tubes, if it slips it's instant release of air.
Make sure you check that screws are not too long because they can easily poke into the inner tube.
Title: Re: tire screws on slicks
Post by: thatdarncat on April 18, 2016, 08:50:02 AM
If you've got tubes I'd be a little concerned without the screws.  If the tires move at all on the bead they can shear the valve stem off the tube.  JMO, but I'd put in the screws...

Like Jay and the others said, the screws were used to keep from tearing off the valve stems ( which leads to a quick loss of air or at minimum having the stem rotate into the rim and not be accessible ) if the tire moves on the rim.

A few observations I've made - some brands of slicks have thicker sidewalls, or more rubber sidewall coating, than other brands. Likewise some specific part number slicks have thicker sidewalls. When I used to run Goodyear slicks the sidewalls were very porous and would leak air right out the sidewall ( it can be checked with the old soapy water trick ). I had to run tubes in those and I used bead screws. I've switched to using Hoosier slicks and I've found that so far they seem to hold air without tubes and I've successfully run some of them without screws. That's not to say there is anything wrong with Goodyear slicks, it's just a characteristic of the size and type I used. Some Goodyears, like the radial slick some of the NHRA stock eliminator guys run, have a thick, stiff sidewall and are usually run without a tube. I don't have any first hand experience with M/T slicks, or the other brands, but my racing friends do and they've told me similar things - it just depends.

Tubes can give you a bit of a safety factor when running slicks, and can help keep from having to add air as often, but also add weight, expense ( the proper natural rubber tubes are very expensive ), and the possible need to run bead screws. If you run tubes you should put some talcum powder in the tire also to keep the tube from sticking to the inside of the tire and also chaffing. 

It can depend also, both if they will hold air and if they will slip on the rim, on whether you are using brand new fresh slicks or used slicks. It does seem to becoming more common for racers not to run tubes or screws than it used to be.
Title: Re: tire screws on slicks
Post by: fekbmax on April 18, 2016, 09:06:04 AM


M/T slicks leak like a siv. Right through the sidewall. They hook like hell and I love um but if your not running tubes you better have Jack stands available any time your car is sitting more than an hour.
JMO.
Title: Re: tire screws on slicks
Post by: cammerfe on April 18, 2016, 05:20:13 PM
The same thing is true of M&H Dragsters, except that it takes several hours to show significant loss. It took me several days to decide to put tubes in mine, back in the day. Slick sidewalls are too thin to hold air very well.

KS
Title: Re: tire screws on slicks
Post by: GJCAT427 on April 18, 2016, 05:37:19 PM
OK I ordered the screws this afternoon. I`ll be busy putting them in this week. That's all I have left to do for Beaver Springs!
Title: Re: tire screws on slicks
Post by: cjshaker on April 18, 2016, 07:10:08 PM
My M/T ET Streets hardly leak at all. Other than when I air them down for traction, I have to add air maybe 2-3 times a summer, and just a couple pounds at that. As far as I know, the only difference between the Streets and a true slick is the grooving to make them DOT legal.
Title: Re: tire screws on slicks
Post by: fryedaddy on April 18, 2016, 08:03:34 PM
i run hoosiers quick time pros on my comet.they dont need tubes or screws in them and they have never leaked ever not even a pound of air.i just put some sticky sealer on the bead last summer and they have not moved or dropped any pressure.jmo
Title: Re: tire screws on slicks
Post by: CaptCobrajet on April 18, 2016, 09:03:30 PM
We ran screws with tubes.......low pressure on the bead would allow slip.  When we went tubeless, and higher pressure, no screws, no slip.  I went 1.21 in 60' in my 3320 lb junk with no screws, tubeless.  Dish detergent on the inside of the sidewall, spread liberally, will stop the seepage through the sidewall.
Title: Re: tire screws on slicks
Post by: TomP on April 19, 2016, 12:49:03 AM
I never use screws. Sure, the tires can move,  but not often and not much and no ripping of the valve stem. Deflate, shake tire around to center tube again and add air.
Title: Re: tire screws on slicks
Post by: Falcon67 on April 25, 2016, 09:11:43 AM
If the tire uses tubes (like the Mustang) it gets rim screws.  For drag radials and no tube, so far I've not had an issue not using screws.  At slower ETs - 12s - I have run MT slicks with no tubes and no screws on a regular Ansen 15" slot without movement.  Mark the tire and wheel with a daub of shoe polish and make passes.  If the tire moves, switch the wheels side-for-side and re-test.  Many times a tire will move a little and when you push it in the other direction it'll take a set and be done.  If it continues to move - add rim screws.

My experience with MT slicks (run 3055s on the cars if using slicks) is that we'll get 75~100 passes before one decides to start losing air.  Usually happens after the 75 run mark on a cool night with good air.  Get a real nice 60' pass about .02 or better than normal.  Next day, one of the tires will be a little flat.   I have some big 33x17 Goodyears on the dragster - one hold air fine, the other won't stay up 3 days.  Those tires haven't been down a track in 4 years.  If it bugs you that much then 1) run tubes or 2) rub the inside of the tire with dish soap (Dawn seems to be the preferred brand) and let it dry then mount the tires. 
Title: Re: tire screws on slicks
Post by: GJCAT427 on April 25, 2016, 11:26:25 AM
I spent Friday After work putting the screws in and Saturday morning mounting the wheels back on the car and fixing a rear tailpipe hanger. I loaded the car on the trailer yesterday and all that's left is to wash it and pack stuff for Beaver.  My truck needed some attention so I`m up in the air as to which truck gets to tow the car, The Powerstroke has a RABS sensor acting up and the Dodge had a tranny hiccup a week ago.
Title: Re: tire screws on slicks
Post by: Falcon67 on April 26, 2016, 01:04:11 PM
Hope you get that sorted quickly.  I like my dead simple 1993 F350 DRW 7.5L gas.  65 MPH all day with a 24' box on the tail end. 
Title: Re: tire screws on slicks
Post by: GJCAT427 on April 26, 2016, 07:07:41 PM
I swapped out the RABS mod behind the glove box with one a friend had that's identical to mine sunday.Iit seems to have cured the problem, I hooked the car and trailer up and went for a short ride the trailer brakes seem week but do come on, gotta adjust the gain and current wheels some more. Still may take the flat bed tho.