M/T ET Street tire question

Just mounted a set of 275-60 ET Streets on my Challenger and I am going to run it down the track soon. I do not have tubes. This is the first time on the track in 20 plus years. Do I need to screw these to the rims?

What is a good starting point for tire pressure? Also what is a good or safe range to run these tires?

Car is 70 Challenger. 472 hemi on pump gas, 4 speed, 4:30 gears.

Thanks

I'd start with 17 psi and go UP from there. If it hooks hard it will most likely spin the rim inside the tire a little, but screws are not mandatory. If the track is good, I will run 19.5 to 20 psi in mine, although I'm running the bigger 295-65 radials. I have been almost as fast on the 275-60's though. CHIP

Are these the Radial or Bias ply Version? If they're radial, you don't use tubes.

They are radials

I run 15 lbs in mine,she seems to like it there best, i started at 20 and made my way down others at the track run the same pressure..

The ET Street Radail may not be the best street strip tire for your car due to the 4 speed I don't know which one would be better, sorry. I do run the MT 315x60x15 on my car and have found that no two tire gauges are exactly the same, I use the same gauge now and run 18 to 22 lbs depending on the track I'm at Buy a good gauge and try different pressures to find out what your car wants

I didn't screw mine. But then again the car was only running 12.0's w/ a 1.65 foot. I can tell you they do need a "break in" period. Mine seemed to start hooking better after the 2-3rd time to the track. And as mentioned 17 is a good place to start.
Whoops radials need more pressure, they aren't made to "wrinkle" they will "cup". Try 20-22lbs. And yeah Hemi + 4 speed + 4.30's =

I have the same tires and a slow car, but I started at 22psi and kept picking up every time I lowered the pressure until I got to 18psi which then hooked hard enough to snap an axle. So I'd say the 17-18psi range sounds like a good place to start too.

No tubes or screws in mine but like I said I'm slow .........

I started with mine at 18 and went lower. Right now I am at 14 and I think it likes it there. But I am on a different track this year. 9secphill mentioned that I should try going back up and see how my 60's vary. Next time out I think I'll try 17 and see what happens. I bought my wheels used and they had screw holes in them. I still haven't installed the screws and I've made maybe 35 passes on them between last year and this past weekend. Not to mention the "street tatts" I leave.. Not sure about a 4spd though. Mark the tire to the wheels and see what happens. I agree, they need to be heat cycled when new.

My car will hook with them anywhere from 15-22+ The more air i have in them, the faster the car 60s.

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My car will hook with them anywhere from 15-22+ The more air i have in them, the faster the car 60s.

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Mine still hooks with lower pressure, but it has kept getting quicker every time I raised the pressure. CHIP