1/2 mile WOT vs. tire pressure? - ZR-1 Net Registry Forums

Paul Workman · 02-10-2013

Saw this on CF ZR-1 page, and it was news to me. Thought I would share w/ y'all.

http://www.tirerack.com/tires/tirete...adj_Zspeed.jsp

Your Thoughts???

p.

XfireZ51 · 02-10-2013

Paul,

Looks like 40psi would be good overall. I think this chart addresses sustained speeds. We won't be up there for very long.

lbszr · 02-10-2013

Interesting

looks like GY GSD3 max load is lowered to 1488 lbs. at 180 mph for the front tires. Still sounds plenty high, but how much downforce is there on a stock setup at 180.

RHanselman · 02-10-2013

When we were doing the mile at Nellis AFB a few years back we used those charts. Good info...

LancePearson · 02-10-2013

In road racing at VIR their standard club's inflation info to new road race course racers with three straights on the course was to add 3-5 pounds to your normal tire pressure which I believe was to keep the sidewalls stiffer and from less flex on cornering. The chart referenced seems like a lot to me and I have a question.

Does it presume high or low aspect ratio tires? I'd think it would be slightly different for the two. With our 40 and 35 aspect ratio tires mine with very small changes in air added seem to make pretty solid changes in air pressure and are much stiffer in terms of side flex with the shorter aspect sidewalls we have.

My 76 is 255 x 60 tires and now we're 275 and 315 and 35 and 40% which are pretty rigid on the car comparatively.

Lance P..

02-10-2013	#1
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,466	1/2 mile WOT vs. tire pressure? Saw this on CF ZR-1 page, and it was news to me. Thought I would share w/ y'all. http://www.tirerack.com/tires/tirete...adj_Zspeed.jsp Your Thoughts??? p.

02-10-2013	#2
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,686	Re: 1/2 mile WOT vs. tire pressure? Paul, Looks like 40psi would be good overall. I think this chart addresses sustained speeds. We won't be up there for very long.

02-10-2013	#3
lbszr Join Date: Nov 2006 Location: dayton,ohio Posts: 424	Re: 1/2 mile WOT vs. tire pressure? Interesting looks like GY GSD3 max load is lowered to 1488 lbs. at 180 mph for the front tires. Still sounds plenty high, but how much downforce is there on a stock setup at 180.

02-10-2013	#4
RHanselman Join Date: Jul 2005 Location: Cresson, TX Posts: 970	Re: 1/2 mile WOT vs. tire pressure? When we were doing the mile at Nellis AFB a few years back we used those charts. Good info... __________________ Ron Hanselman Founding Member #80 CM Lifetime Member #1093 1991 #383 Twin Turbo 1993 #099 Ruby, Jeal 368 w/Snake Skinner body 1961 White with Red Int

02-10-2013	#5
LancePearson Join Date: Dec 2012 Location: Chester, Virginia Posts: 457	Re: 1/2 mile WOT vs. tire pressure? In road racing at VIR their standard club's inflation info to new road race course racers with three straights on the course was to add 3-5 pounds to your normal tire pressure which I believe was to keep the sidewalls stiffer and from less flex on cornering. The chart referenced seems like a lot to me and I have a question. Does it presume high or low aspect ratio tires? I'd think it would be slightly different for the two. With our 40 and 35 aspect ratio tires mine with very small changes in air added seem to make pretty solid changes in air pressure and are much stiffer in terms of side flex with the shorter aspect sidewalls we have. My 76 is 255 x 60 tires and now we're 275 and 315 and 35 and 40% which are pretty rigid on the car comparatively. Lance P..