A tire question

Suspension Tuning, Troubleshooting, Design and Discussion

Moderators: David Lemmond, Dave Morgan

Post Reply
Message
Author
505r10
Posts: 34
Joined: Sun Apr 11, 2010 6:17 pm

A tire question

#1 Post by 505r10 » Mon Apr 26, 2010 8:54 pm

A tire question. My truck is trying like hell to hook up but not quite there yet (street use so far). I noticed the rear tires 31x16.5 nearly new ET streets on 12 inch wheels (actual tread width of 12.5") are rolling up the tread in the center but are smooth on the edges. About one inch on the inside and outside. Both of the tires look identical. My thinking is that there is too much air in them but they only have 11 psi in them right now. On the street it'll leave two black lines from the outside edge of the tire and a fairly solid black mark where the tread is rolled up. Higher air pressure and it just cooks them. It weighs 3820 and if I run it up against the converter it hooks better than at an idle or near an idle.

Basic specs are full size long bed chevy truck, 505, turbo 400, 10 inch converter stalling at about 4200, 4.88 gears. The picture is just from goosing it across my carport but they look pretty much like that after nailing it out of the hole. Only thing is the grain pattern on the tire is a little finer. Any opinions/advice/wisecracks welcome I haven't had a race car in a long time and am trying to sort this out before I go to the track. Getting put out in the first round is no fun. Thanks



Roger
Attachments
grain is coarser than when tires are coming off the line
grain is coarser than when tires are coming off the line

User avatar
supernova
Posts: 2552
Joined: Sat Feb 02, 2008 7:35 pm
Location: Ft.Worth Tx

Re: A tire question

#2 Post by supernova » Mon Apr 26, 2010 9:47 pm

Well any time you spin the tire it's going to look like that. Trying to make traction on the street is just about worthless in my book especially if your going to take it to the track :scratch: . I would just take it to the track and work with it there because it will be totally different. :thumb: :thumb: :thumb:
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

User avatar
Speedster
Posts: 183
Joined: Mon Feb 08, 2010 2:35 pm
Location: Aloha, Oregon

Re: A tire question

#3 Post by Speedster » Mon Apr 26, 2010 10:03 pm

have you tried it with more air? maybe with more air you will get a bigger foot print?

User avatar
Craig W.
Posts: 1257
Joined: Thu May 12, 2005 11:01 am
Location: Columbia, KY
Contact:

Re: A tire question

#4 Post by Craig W. » Tue Apr 27, 2010 6:38 am

505r10 wrote:My thinking is that there is too much air in them but they only have 11 psi in them right now.
Roger
Looks like too much air pressure to me too. Try dropping 1 psi at a time until you get even contact.
Craig Watson
2QuickNovas Racing
5.23@131

Sponsors:
AEM Electronics
Carnivore Performance
Rapp Racing
VFN Fiberglass
Fast Shafts

505r10
Posts: 34
Joined: Sun Apr 11, 2010 6:17 pm

Re: A tire question

#5 Post by 505r10 » Wed Apr 28, 2010 11:41 am

Craig W. wrote:
505r10 wrote:My thinking is that there is too much air in them but they only have 11 psi in them right now.
Roger
Looks like too much air pressure to me too. Try dropping 1 psi at a time until you get even contact.


I haven't run them lower than 11 psi. I didn't know if conventional wisdom applied to drag type tires or not. I'm going to start lowering the pressure 1/2lb at a time to see if it starts covering the whole tire. Thanks


Roger

427belair
Posts: 284
Joined: Tue Aug 15, 2006 10:23 pm
Location: greatfalls,mt

Re: A tire question

#6 Post by 427belair » Wed Apr 28, 2010 11:07 pm

I know its apple to oranges, but my 28x10.5w on a 12" rim like 9.25-9.5 on a greasy track. Usually bigger slicks like less pressure. Also do you run tubes?

505r10
Posts: 34
Joined: Sun Apr 11, 2010 6:17 pm

Re: A tire question

#7 Post by 505r10 » Thu Apr 29, 2010 10:19 pm

427belair wrote:I know its apple to oranges, but my 28x10.5w on a 12" rim like 9.25-9.5 on a greasy track. Usually bigger slicks like less pressure. Also do you run tubes?

Sorry for the late reply. Yeah they've got tubes in them. I did let them down some and they're much worse. I'm going to try to get to the local track's test and tune next Thursday night. I'm sure it'll do much better at the track.


Roger

Post Reply

Who is online

Users browsing this forum: No registered users and 37 guests