On the scales - Page 2

lloyds1 · #21 (**permalink**) 10-22-2009, 09:33 PM

I believe the race/street bias ply tires (Billboards & TDs) are supposed to be at about 18-20psi.

dcdoug · #22 (**permalink**) 10-23-2009, 06:59 PM

My tire pressures are the same all around - about 26 psi, which was where the Ford dealer had set them that did the alignment. Will more psi or less psi increase the wandering/darting, or does that not really impact it specifically?

patrickt · #23 (**permalink**) 10-23-2009, 07:52 PM

Doug, as a general rule, the front tires on our cars are going to have a couple of pounds more than the rear. One way you can get a feel for the best pressure is by using a pyrometer to measure the temps on the inside, middle, and outside of your tires. You then adjust the pressure so the middle temp is as close to the other two as possible.

tmareina · #24 (**permalink**) 10-23-2009, 08:28 PM

I second JJ Cobra's recommendation...I had Tom Lucas at FE Specialties do my car and the handling was exceptional...on the track as well as the twisty roads in the Sierras (Quincy) where I live. You won't be sorry.

Tom Mareina

patrickt · #25 (**permalink**) 10-23-2009, 08:31 PM

Quote:

Originally Posted by tmareina

I second JJ Cobra's recommendation...I had Tom Lucas at FE Specialties do my car and the handling was exceptional...on the track as well as the twisty roads in the Sierras (Quincy) where I live. You won't be sorry.

Except when he writes the check for the round trip transportation costs to have his car trucked to Sacramento from DC.

tmareina · #26 (**permalink**) 10-23-2009, 08:36 PM

Well Gunner, from Sac, wrote the first thread and that was the one I was referring to. DC came in much later.

Sorry for the confusion.

Tom

patrickt · #27 (**permalink**) 10-23-2009, 08:44 PM

Doug's made of money... he darn well might ship is car off to Sacramento for a quick alignment.

Rwillia4 · #28 (**permalink**) 10-23-2009, 09:00 PM

Darting around sounds like something in the front end may need tending to (like a tie-rod end)

Quote:

Originally Posted by CHANMADD

The biggest mistake new Coba drivers make is to thinkthat the car is going to drive like a BmW.

Mine handles just like a BMW

lloyds1 · #29 (**permalink**) 10-23-2009, 09:48 PM

Dennis Olthoff told me to run my TD's at 18psi, it seemed to make the car more compliant than running them at the higher tire pressure.

Also, remember that race tires need to get up to temperature before handling correctly.

Also, the fact that the north east has some pretty rutted out roads doesn't help either.

Quote:

Originally Posted by dcdoug

My tire pressures are the same all around - about 26 psi, which was where the Ford dealer had set them that did the alignment. Will more psi or less psi increase the wandering/darting, or does that not really impact it specifically?

Gunner · #30 (**permalink**) 10-23-2009, 09:55 PM

Quote:

Originally Posted by lloyds1

Dennis Olthoff told me to run my TD's at 18psi...

Man, you'll listen to anyone, won't you?

jperickson2001 · #31 (**permalink**) 10-24-2009, 09:02 PM

I went to the 49'er truck stop at West ElCamino ave. and I-80. Fill your gas tank up and then subtract 8lbs. per gallon. You can get it front/rear divided. Cheap. My FFR was 2160lbs - 100 lbs for fuel for 2060lbs. I should have taken all the tools and jack out when I did it also but I didn't.

Rick Parker · #32 (**permalink**) 10-24-2009, 11:02 PM

18lbs is not enough air pressure, the sidewalls will flex too much. Cold should be near 25 in the front and 24 in the rear shooting for as close to 32 & 30 when things get real hot under track usage. Reccomended by Roger Kraus Racing.
18 lbs is too soft for responsive driving even on the street. IMO I base this on my having used Goodyear Blue Streak Sport Car Specials for several years. They are a very similar tire just a different tread.

ERA Chas · #33 (**permalink**) 10-25-2009, 07:20 AM

"Cobra Make, Engine: FFR1509, 302 EFI, 350hp 1/4 ml 12.20@125mph"

Perickson-how do you get 125mph out of 350 HP?

What Rick said x 2. I've had 4 sets of TD's and one set G'years.

UB DRMNG · #34 (**permalink**) 10-25-2009, 12:52 PM

Quote:

Originally Posted by jperickson2001

I went to the 49'er truck stop at West ElCamino ave. and I-80. Fill your gas tank up and then subtract 8lbs. per gallon. You can get it front/rear divided. Cheap. My FFR was 2160lbs - 100 lbs for fuel for 2060lbs. I should have taken all the tools and jack out when I did it also but I didn't.

Depending on the formulation, gas weighs more like 6lb per gal (5.9-6.4). Water is a bit over 8lb per gal. But this will help make up for the tools!

ERA Chas · #35 (**permalink**) 10-25-2009, 06:09 PM

Quote:

Originally Posted by UB DRMNG

Depending on the formulation, gas weighs more like 6lb per gal (5.9-6.4). Water is a bit over 8lb per gal. But this will help make up for the tools!

Now I see how you got a 600hp trap speed...

jperickson2001 · #36 (**permalink**) 10-25-2009, 09:55 PM

Quote:

Originally Posted by UB DRMNG

Depending on the formulation, gas weighs more like 6lb per gal (5.9-6.4). Water is a bit over 8lb per gal. But this will help make up for the tools!

Sorry about that, 6 lbs is better. It has been a while since I used the formula.

pgermond · #37 (**permalink**) 10-25-2009, 10:08 PM

Check with the River City Club in Sacramento. A few years back they had a weigh-in at Winston Cup shop here in Roseville off of Foothills Blvd. All four corners with independent scales. Perfect balance setup.

dcdoug · #38 (**permalink**) 11-08-2009, 07:49 PM

Quote:

Originally Posted by patrickt

Doug, as a general rule, the front tires on our cars are going to have a couple of pounds more than the rear. One way you can get a feel for the best pressure is by using a pyrometer to measure the temps on the inside, middle, and outside of your tires. You then adjust the pressure so the middle temp is as close to the other two as possible.

I adjusted the tire pressure today to more like 26-27 in the rear and 28-29 in the front (the pressure is exact in all tires, but I am not sure of the completely cold temp as I drove about 1/2 mile to the gas station before filling them, so they might have been warmed up slightly - will check again when they are cold). Slightly rougher ride, but the car handles much better. I think that was it. I will get the cross weights done at some point on the CACC scales too just to be sure, but it's much better now.

patrickt · #39 (**permalink**) 11-08-2009, 07:53 PM

Quote:

Originally Posted by dcdoug

I adjusted the tire pressure today to more like 26-27 in the rear and 28-29 in the front (the pressure is exact in all tires, but I am not sure of the completely cold temp as I drove about 1/2 mile to the gas station before filling them, so they might have been warmed up slightly - will check again when they are cold). Slightly rougher ride, but the car handles much better. I think that was it. I will get the cross weights done at some point on the CACC scales too just to be sure, but it's much better now.

Today was a nice day for a ride. I had her out for quite a bit just in case we don't get any more nice weather until I pop her in to the bag later this month (or maybe early December). High 60's is my favorite driving temperature.

dcdoug · #40 (**permalink**) 11-08-2009, 08:07 PM

Quote:

Originally Posted by patrickt

Today was a nice day for a ride. I had her out for quite a bit just in case we don't get any more nice weather until I pop her in to the bag later this month (or maybe early December). High 60's is my favorite driving temperature.

One of the nicest days of the year today. I could have driven all afternoon. It's not like the skins are worth watching. What a train wreck. At least they made an effort in the 2nd half so I didn't have to swear off them forever.