tire pressure?

-
j par

j par

Well-hung Member
Joined
Jul 2, 2014
Messages
33,695
Reaction score
21,036
Location
Portland Oregon
15 × 10.5 × 26 street/strip slicks. 73 duster gutted. So far 20psi ? How low can I go before #1 the tires fall off! ?!! #2 handling at the high end of the track at speeds approaching and 1 day hopefully over 100 miles per hour???!?
 
I used to run my MT ET streets 15 x 10.5 x 26 at 15 psi with a 383 4 speed launching at 6000 rpm. Launched great and good down track handling.
 
IF you don't have screw threw the rim to keep the tire(bead) from slipping, i wouldn't go much below 15.

IF the bead is locked, keep going lower until 60's falls off or top end gets a little bit mushy!
 
Thanks men! No beed. Anymore info or experience with this setup and would be appreciated:prayer::D
 
j par,
What kind of street strip slicks?
If they are QT pro's I wouldn't be afraid to go down to 13 lbs.
That is what I run on my 10.30 Duster.

 
If you are only doing 100 mph in the 1/4, I would keep the pressure on the high side (like between 15-20 psi). You won't be spinning unless the track prep is atrocious. To answer your other question, I ran my Hoosier QTP's at 13.5 psi. I have run them as low as 11 psi, but the car did the "slick shake" on the big end of the track pretty bad....not fun. I run Hoosier drag radials now at 19 psi...VERY stable at high speed, and still run the same ET as I did with the QTP's.
 
womanator said:
j par,
What kind of street strip slicks?
If they are QT pro's I wouldn't be afraid to go down to 13 lbs.
That is what I run on my 10.30 Duster.

Click to expand...

I'll see if I can get a picture up.I like to tell my friend that these tires called me up off of Craigslist and beg me to get them off a slow Chevy and get on a Mopar! they are slick after all, they want to go fast! Lol they know I like all muscle cars, but my passion is always mopar! View attachment 20140623_161606.jpg
 
flyfish said:
If you are only doing 100 mph in the 1/4, I would keep the pressure on the high side (like between 15-20 psi). You won't be spinning unless the track prep is atrocious. To answer your other question, I ran my Hoosier QTP's at 13.5 psi. I have run them as low as 11 psi, but the car did the "slick shake" on the big end of the track pretty bad....not fun. I run Hoosier drag radials now at 19 psi...VERY stable at high speed, and still run the same ET as I did with the QTP's.
Click to expand...

"Slick shake"?!! I've only took 3 passes with the slick so far and I remember at the high end in 3rd gear it had a wild shake like the drive line was out of balance or something. I have to shift into 4th gear just before the finish line but the end of 3rd year seems a bit wild.
 
j par said:
"Slick shake"?!! I've only took 3 passes with the slick so far and I remember at the high end in 3rd gear it had a wild shake like the drive line was out of balance or something. I have to shift into 4th gear just before the finish line but the end of 3rd year seems a bit wild.
Click to expand...

What I'm referring to is when you get the air pressure too low and the back end of the car sways side to side. Not a vibration, but a feeling like the car is spinning on ice and about to loose control....its a bit of a white knuckle ride when that happens.

If you are having vibration issues at high speed, check drive shaft balance, tire balance, transmission mount (if it is bad, it would give the same vibration), etc.
 
Take the car to a piece road and launch the car. Go back and look at the pattern. If you have heavy dark strips on the outer of the tire pattern you need to add air. If the center of the pattern is dark you need to remove air. Once you have a somewhat even pattern you should be ok.
 
Dart Sport 360 said:
Take the car to a piece road and launch the car. Go back and look at the patter. If you have heavy dark strips on the outer if the tire you need to add air. If the center of the pattern is dark you need to remove air. Once you have a somewhat even pattern you should be ok.
Click to expand...

I used something similar to this on my old 4x4 truck...level ground....steering wheel straight....chalk like across the tread. Push it a few revolutions of the tire. Chalk on the center underinflated, on the outsides of the tread overinflated....
 
Thank you men! From the few passes I taken @ 20 psi there is
about 1/2 inch on each side of the tires that appear different?
Maybe not touching?
 
You must log in or register to reply here.
-

Back
Top