Pressure for M/T ET Street Rs?

I'm going to try my new pair of Mickey Thompson drag radials out tomorrow at Barona. They are the new version they came out with called the ET Street R in the 255/15 size.

What pressure do you guys recommend? I was thinking maybe 17-18 psi?

The car is a 3600 pound mild 440-powered Plymouth Satellite with #3400 Super Stock springs, 90/10 Calverts, 3.91 gears.

In the past it's done a best 60 foot of 1.68 with Hoosier Quicktime Pro D.O.T. bias ply slicks at about 16 psi. It usually runs in the low 7.90s in the 1/8 mile. Thanks!

I'm running 17.5 psi in my 275/60s, on an 8" wheel.
My car is quicker with the Mickeys than the 11.5x28 QTPs i have.
1.60-1.62 shorts with a string of 7.20s this last Sunday.

I've been running the standard ET Street Radials for a few years, 255/60's. I run them at 17.5 lbs, and typically go 1.61 & 7.39 with 3.91's. Been looking at the new R's. Its interesting to me that they list the sizes pretty differently between the old ET Street Radials 255's, and the new ET Street R 255's. I called Mickey Thompson a while back to ask why, and if this was really a completely new carcass, and the guy said the new R is based on the 275 Street Radial Pro., but honestly, I don't think the guy really knew too much about them, was just giving the company spiel.

I'm also looking at the ProBracket Radial, but would have to adjust gearing to do that, as they are a 28" tire.

To address the op: I'd start at 18psi and adjust from there.

I run mine at 19# same weight as yours, more power.

Start at 16.5 and go up .5lb per pass. I'd say 18.5-19 will be the best for you.

19# in my husband's Challenger at Norwalk yielded the best 60 foot times.

There are several things you need to kep in mind, not all tire gauges read the same on the same set of tires tested back to back at the same track one after another I've used three different low pressure Morso gauges that read 3 lbs difference,9.0 to 12.0lbs I ended up buying and using a very expensive accurate low pressure C gauge for my bias tires, I don't loan it out after finding out that there are people at the races that will use a borrowed low pressure tire gauge on there street tires and ruin that gauge, twice I learned that lesson twice , No MAS The other thing to keep in mind is to use only your gauge on your tires and go by the 60 ft. times to find the best pressures for that track that day Another thing about tire pressure is altitude and barometric pressures as well as outside air temps. and tire temps. all affect the tire pressure readings I use to use my fingertips and rub them lightly across the bias ply tire surface to see if the texture was the same all the way across from the outer edge to the inner edge, to low of pressure will make a rough, smooth, rough, smooth and rough again on the inner and outer edges as well as in the center of the tires To much pressure will make the inner and outer edges smooth from no conact and the centers rough Try using 1/2 lb. changes at first and then use 1/4 lb increments to find the pressure on your gauge that your tires work the best at I did find that on my old pump gas Duster(10.0 at 134 MPH in the 1/4) on the original M/T ET Street Radials, 315x60x15 on 10 or 12 inch wide rims that they liked between 18 to 22 lbs, depending on track prep and track altitude. IHTHs

Thanks for all the advice!

I had mixed results with the drag radials last weekend. It was really hit or miss and there didn't seem to be any rhyme or reason to if it would hook or not. I got in nine runs, and maybe four had 60 foot times as good as the Hoosier Quicktime Pro D.O.T. bias ply slicks I used to use.

Sometimes I'd make a run where they would hook good, come back around and do another run back to back not changing anything and it would spin.

Once, they even hooked out of the hole, then started spinning bad about 40 feet out. They seemed to work best at 19 psi. Racers were complaining about the track prep that day so maybe it wasn't an apples comparison with my Hooisers.

Maybe I need better shocks? I'm just running long Monroematic truck shocks with my Super Stock springs. I'm also using an adjustable pinion snubber, maybe I should ditch that?

I've been able to 60 foot as good as 1.68 in the past and usually 60 foot around 1.72 which I think is decent for my combo that only runs 7.90s in the 1/8 mile. Best 60 foot yesterday was a 1.73 so the drag radials aren't totally hopeless.

They do drive about 100 times better on the street than the Hoosiers did.