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      08-22-2007, 01:37 PM   #1
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Drag Racing Tire Pressure? How important is it?

On my way to the Drag Racing Strip soon.
Last time I ran a 13.1 @ 106 in 90+F weather. Today its going to the 75 F max. So hopefully I can get better times.


Two questions:

1. Whats the best tire pressure (sport package) for best performance?

2. Does it make a difference?
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      08-22-2007, 02:56 PM   #2
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It does make a difference. I don't know the numbers on this car though, I'd like to find out.

1. I think best tire pressure would vary upon the day. Track temps, track condition, and which tire you are using would all factor in. Play with your tire pressures and see how it affects your 60'. Of course, your launch technique would be critical as well.

2. Yes.
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      08-22-2007, 02:58 PM   #3
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I would say mid to low 20's...
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      08-22-2007, 03:47 PM   #4
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You said youre running on the sport package right? Therefore youre on the RFT's. Unfortunately, you cant do much in terms of tire pressure because the sidewall is so stiff, youll get no benefit from lowering the pressure. That being said, raise the front pressure about 10lbs so you have less contact patch and drag, that could help.

Also, try not to go through the waterpit. If you have to, dont do a burnout, youre not on slicks. Just do a quick spin to get the water off. Again, try to go around the water if you can.
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      08-27-2007, 04:35 PM   #5
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I wouldn't worry about rear tire pressures at all with RFTs. Pump the hell out of the fronts, at least the max rated pressure. And what HyperM3 said, although I typically go around the water and do a quick spin / burnout just to get the crap off the tires. No more than 1 second just to get a revolution or two so anything stuck to your tires gets kicked off... Although without LSD who knows if both tires would even spin...
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      08-27-2007, 04:40 PM   #6
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Oh, and one last thing. If you do decide to do a burnout(or anyone for that matter) theres nothing worse than melted rubber bits on your lower rear bumper.

Trick-O-The-Trade = Spray WD-40 all over your rear bumper behind the tires. The rubber bits wont stick and its easy to clean off. Harmless to the paint too.
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      08-28-2007, 11:18 AM   #7
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Quote:
Originally Posted by Chowbow View Post
I wouldn't worry about rear tire pressures at all with RFTs. Pump the hell out of the fronts, at least the max rated pressure. And what HyperM3 said, although I typically go around the water and do a quick spin / burnout just to get the crap off the tires. No more than 1 second just to get a revolution or two so anything stuck to your tires gets kicked off... Although without LSD who knows if both tires would even spin...
So for non-RFT, what is the optimal pressure for the front and rear? 42psi for front and 32psi for rear?

Thanks,
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      08-28-2007, 11:20 AM   #8
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Quote:
Originally Posted by baron View Post
So for non-RFT, what is the optimal pressure for the front and rear? 42psi for front and 32psi for rear?

Thanks,
Baron
That would be too high in the rear. I would bring it down to 25lbs and see how it feels at that point. Again, still dont go through the bleachpit if you dont have to and if you do, just one quick spin to get all the water off.
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      08-28-2007, 12:21 PM   #9
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I'd probably put more in the fronts. Whatever the max pressure is on the tire, I'd put that amount in the fronts. Rears, start at 30-ish and go lower as you need to. Honestly, street tires are pretty junk at the track and DRs make a huge difference. If you're into it and get faster and want to improve your times, I'd try to find a 15" or 16" wheel and mount a set of DRs on there for the strip.
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      08-28-2007, 04:49 PM   #10
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Thanks, hopefully there is an airpump at the track.
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      08-28-2007, 05:54 PM   #11
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If you're in the BA, then neither Sears or Sac Raceway has one. Just buy one of those ones that plug into your cigarette lighter. I have one and have found it useful not only at the track, but rather than pumping up my tires at the gas station I do it at home.

Which track you going to and when? I might do a few baseline runs in mine soon...
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      08-28-2007, 06:30 PM   #12
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Quote:
Originally Posted by Chowbow View Post
If you're in the BA, then neither Sears or Sac Raceway has one. Just buy one of those ones that plug into your cigarette lighter. I have one and have found it useful not only at the track, but rather than pumping up my tires at the gas station I do it at home.

Which track you going to and when? I might do a few baseline runs in mine soon...
I already have a big pump at home (plugs in wall), so probably not worth it buy another one. I guess I will just pump it at the track. I will be going to Sears Pt tomorrow for Wednesday night drags. Have you been to this event before?

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      08-28-2007, 06:40 PM   #13
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Yeah, but I really don't like going to Sears Point for 1/4 mile drags. The track is slightly uphill, and hopefully they have fixed the issue with the launch pad being a little uphill... otherwise you roll backwards while staging.

There's typically a billion slow cars there running 15s or slower and it's all bracket racing which means easy eliminations. I simply don't like bracket racing and I go to the track just to race myself and my car.

I much prefer paying about $40 at Sac Raceway for a Test and Tune night. It's a much better prepped track and IMO, runs much smoother than Sears Point. Plus, the crowd that goes there is much less "ricey" if I had to say it...
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      08-29-2007, 03:20 PM   #14
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Quote:
Originally Posted by Chowbow View Post
Yeah, but I really don't like going to Sears Point for 1/4 mile drags. The track is slightly uphill, and hopefully they have fixed the issue with the launch pad being a little uphill... otherwise you roll backwards while staging.

There's typically a billion slow cars there running 15s or slower and it's all bracket racing which means easy eliminations. I simply don't like bracket racing and I go to the track just to race myself and my car.

I much prefer paying about $40 at Sac Raceway for a Test and Tune night. It's a much better prepped track and IMO, runs much smoother than Sears Point. Plus, the crowd that goes there is much less "ricey" if I had to say it...

I took your advice and I wont' be going to Sears Pt today. Will probably plan a trip to Sac Raceway in the future. Thanks.
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      08-29-2007, 07:38 PM   #15
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Not a problem... I used to frequent Sac Raceway about once or twice a month since I went to school at UC Davis and was so close to it... Such a better track IMO. Let me know when you run up there and I may join you on a TnT night. Wanna do a baseline run, but I'm going to get a baseline dyno done first, hopefully this week.
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