Hi,
I have a fairly well used set of Victoracers (slick at the back, very little tread on the fronts). I picked them up second hand from a guy.

I feel like I'm getting less grip from them that I did on my Potenza RE730's.

I have an '86 951 with some minor mods, maybe running 250 hp, so it's not insanely powerful.

They break without warning - is this par for the course for R compunds ? They also slide very quietly

I've been running 40 psi all round for autocross. Should I be running higher pressures ? What experience have other people had ?

How long does a treatment of Formula V last ?

Thanks,
Mike.

 

I run victorracers and they work quite well when warm . Cold they are like
driving on ice. Didn't have a problem all summer but last weekend with the cold temps it took two runs just to get them warm enough to stick.

 

40 psi is WAY to high for victoracers. Autocross starting pressures should be 31-32. Hot pressures in a DE (track day) enviroment should be no higher than 33 or 34.

 

Re: your Victoracers.

Three of the main items that effect R compound tires are:

number of heat cycles
how old they are (week and year are on the side of the tire)
just worn out.

I've used up lots of Victoracers over the year at Auto-X events. By the time they get "smooth" they are pretty well used up.

Also, as mentioned above 40 PSI seems high and cold used up tires don't give much grip. A pyrometer will help you determine the correct preasure. Somewhere on Rennlist there is some very good info this subject.

Good luck and...
Have Fun! Steve

PS:Race tires don't make a lot of noise like street tires. They also should be very predictable. Victoracers are a good tire. Try a new set you should be happy with them.

 

Vracers also like a fair amount of negative camber......bout -2 on my car, but let your pyrometer be your guide.

 

Those tires are past being worn and/or aged out. Toss them and get a fresh set.

 

Like said above - pressure is too high, and the tires are probably beyond their 'heat cycle' sweet spot.

That's why I don't believe in buying used R-compounds. The tires may look ok, but you can't tell until you start sliding all over the place that they are worn beyond usefulness!

Just my $0.42,
-Z-man.