How Much PSI?

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hugger73hatch
Posts: 360
Joined: Sun Oct 21, 2007 10:42 pm

How Much PSI?

#1 Post by hugger73hatch » Mon Apr 20, 2009 9:14 pm

Just wondering what everyone's thought is on psi in bias ply slicks. This past weekend was first time out this year and first time with Caltracs and split monos. I ran 18psi in a 28/9/15 MT ET drag. Never ran that much before. Just curious to see what everyone is running. Before the caltracs at this track I would normally have about 12 in them and still spin.
73 Nova Hatchback, 408 Small Block 13-1, Iron Heads, 6.972 @ 98.362, 1.468 60', 3450 lbs, still tuning
28 x 9 Slick, N/A

http://www.esquireservices.net
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vegaracer
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Location: Wyoming, Ontario, CANADA

Re: How Much PSI?

#2 Post by vegaracer » Mon Apr 20, 2009 9:18 pm

In my car with 32/14/15 I run 9 psi. In the other car with 34.5/17/16 we run 5-3/4 to 6 psi.
Feenstra's Towing

1973 Vega
434 SBC, N.A.
Powerglide
9.01 @ 146
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hugger73hatch
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Re: How Much PSI?

#3 Post by hugger73hatch » Mon Apr 20, 2009 9:20 pm

What do you find the benefit in running it that low? More consistency, better et, etc...just curious.
73 Nova Hatchback, 408 Small Block 13-1, Iron Heads, 6.972 @ 98.362, 1.468 60', 3450 lbs, still tuning
28 x 9 Slick, N/A

http://www.esquireservices.net
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427belair
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Joined: Tue Aug 15, 2006 10:23 pm
Location: greatfalls,mt

Re: How Much PSI?

#4 Post by 427belair » Tue Apr 21, 2009 7:16 am

With that size slick I would try 11-13 psi
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vegaracer
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Re: How Much PSI?

#5 Post by vegaracer » Tue Apr 21, 2009 11:57 am

If I go any higher in pressure the slick just spins. I have no idea why we run so little in the big tires.
Feenstra's Towing

1973 Vega
434 SBC, N.A.
Powerglide
9.01 @ 146
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drummondracing
Posts: 238
Joined: Thu Oct 12, 2006 1:12 pm
Location: Colonial Beach VA If I am not at home or the track then I am probably at HOOTERS

Re: How Much PSI?

#6 Post by drummondracing » Tue Apr 21, 2009 5:49 pm

Hugger, I saw you at the beach sunday but didnt get a chance to ctach up with you and shoot the breeze. I usually have the best luck with my psi @ 11-11.5 psi. You may just have to keep fooling with it untill you find the sweet spot. Maybe on a friday night. Also the track wasnt very good sunday either. all my guys 60ft times were off by about 2-5. Your best bet is to hit MIR on a sunday for TnT that track is dead on on snday after friday nights and all day saturday racing. :thumb:
74 chevy luv 355 sbc bracket car
70 Nova SS bracket / t.n.t car.
(Yes REAL SS 396 DISCS 12B0LT ETC)

WANTED DEAD OR ALIVE 68-74 NOVAS




TOO MUCH IS NOT ENOUGH!!!!!!!!!!!!!!!!
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stroker1
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Re: How Much PSI?

#7 Post by stroker1 » Tue Apr 21, 2009 6:16 pm

With 28x10.5 I ran 12.5-13 on my S10 with 1.38 60s. I have 2 passes on my 29.5x10.5 and I have been running 13 psi so far.
'87 S10 stock suspension, Caltracs, 9" rearend, 1.82 Glide, 383 SBC,
Brodix Track1 Heads, 14:1 compression, 180 shot plate,
2" tube Hussler Headers, 1.38 60ft., 6.20 ET 1/8th, 109 MPH,
Still Tuning, more to come.
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hugger73hatch
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Re: How Much PSI?

#8 Post by hugger73hatch » Tue Apr 21, 2009 8:25 pm

drummondracing wrote:Hugger, I saw you at the beach sunday but didnt get a chance to ctach up with you and shoot the breeze. I usually have the best luck with my psi @ 11-11.5 psi. You may just have to keep fooling with it untill you find the sweet spot. Maybe on a friday night. Also the track wasnt very good sunday either. all my guys 60ft times were off by about 2-5. Your best bet is to hit MIR on a sunday for TnT that track is dead on on snday after friday nights and all day saturday racing. :thumb:
Yeah I normally run pretty good at MIR, but I think they got bikes this weekend and I am planning on running in the all out qualifier the following weekend. Anybody ever been to a Super Chevy Show Test N Tune? They have one at VMP Friday, but I'm figuring a waste of time with the crowds.
73 Nova Hatchback, 408 Small Block 13-1, Iron Heads, 6.972 @ 98.362, 1.468 60', 3450 lbs, still tuning
28 x 9 Slick, N/A

http://www.esquireservices.net
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chpcamaro
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Location: socali

Re: How Much PSI?

#9 Post by chpcamaro » Wed Apr 22, 2009 12:17 am

i agree 11-11.5 is what i use i have the 10.5 w's tho
best to date N/A 8.91@153
psca westcoast heads up racing open comp
67 Camaro RS/SS
BBC Powerglide 4800 stall 4.11 29.5x10.5W
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BUDGETRAT
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Joined: Sat Apr 15, 2006 11:08 pm

Re: How Much PSI?

#10 Post by BUDGETRAT » Wed Apr 22, 2009 9:59 pm

I run the same size @14psi.Run1.38-1.40 60ft and 9.86-9.90 in 1/4
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