Subaru Tire Pressure Advice Needed

General chat that fellow COM'ers may be interested in.
Post Reply
cuda6666
Speed Racer
Speed Racer
Posts: 540
Joined: Wed Feb 22, 2006 11:54 am

Subaru Tire Pressure Advice Needed

Post by cuda6666 » Wed Sep 20, 2006 9:50 am

Can anyone give me a ballpark for cold pressures (f/r) for RA1s on a Subaru?

Thanks

RyanC
Speed Setter
Speed Setter
Posts: 147
Joined: Tue Jul 05, 2005 4:56 pm

Post by RyanC » Wed Sep 20, 2006 11:16 am

I start around 32f/r and target hot temps of 39-40psi. Toyo recommends 38-40 hot. I know some other guys prefer staggered pressures but my suspension is happiest with equal front/rear pressures

User avatar
rajito
Speed Racer
Speed Racer
Posts: 595
Joined: Thu Dec 18, 2003 11:33 pm

Post by rajito » Wed Sep 20, 2006 11:19 am

It depends on way too many things - how cold the track is, how many laps you plan to run, etc. I do what Ryan said - start off with 30-31 hot and run around the track, and adjust the pressures afterwards to target 39-40psi hot.

Raj
#66 SuperSlowGT
Silver 2004 Nissan 350Z

User avatar
zip4zat
Speed Racer
Speed Racer
Posts: 236
Joined: Sun Oct 09, 2005 7:31 pm

Post by zip4zat » Wed Sep 20, 2006 12:36 pm

the biggest factor is what kind of subaru you are running and what your suspension setup is. Other environmental factors will also affect you tires, but you can figure that out when youre at the track

In my wrx i ran 30/30 ish and would get things up to 40 hot. but I had a wagon so drifting had more to do with heating the tires.

In the Sti, I run staggered pressures all around and dial it in at the track. Ive had to run as low as 24 cold to keep the tires from going away after half dozen laps.
Joe Lu
#24 ST1 STi

WillM
Administrator
Administrator
Posts: 1453
Joined: Mon Oct 06, 2003 10:14 pm

Post by WillM » Wed Sep 20, 2006 2:05 pm

I have no experience with the RA-1's on a Subie, but have a decent amount of knowledge about RA-1's in general.

38-40 is where you want to end up "hot". Anything over 40 is not good. You should use a good-quality gauge to take and set pressures with. I would also recommend that you check your gauge against at least one other. Even a 1/2 pound difference can be a lot (ie: your gauge might say 40, but the actual pressure could be 40.5, etc).

I usually start the day at 32. By the end of the first run session (at NHIS), temps are usually up to the 38-39 mark. By the 2nd run session, they'll be up to 40ish. I may vary the starting PSI up or down by a tick or two, depending on track conditions and ambient temperatures. I usually do not add air between unless the pressures come in below expected pressure after the 2nd run session. For the most part, I'll bleed down as required. If track and weather conditions are the same on the 2nd day, I'll start the day with whatever pressures the tires are at. I'll continue to check pressures occasionally, but will not bleed or add air.

Toyo used to have a tech article on their website, but I could not find it.

In any event, much of this article is taken from what Toyo had published. The linked article goes to a Mitsu/Evo site, but the info carries over. :)

- Will
96 Miata #72 SC
PRA 4 :sunny:

cuda6666
Speed Racer
Speed Racer
Posts: 540
Joined: Wed Feb 22, 2006 11:54 am

Post by cuda6666 » Wed Sep 20, 2006 2:44 pm

Thanks, guys...Its' nice when the answers don't come in all over the map.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest