Lowest Safe air pressures for drag racing on Drag Radials

[prostreeter600]

First off all my info is in my sig. Truck race weight is right at 5900# . RCSB. Last time I ran it it spun out of the hole. I was running 28 in the front and 26 in the rear . Track prep wasn't the best . How low can I go and still safely run 140--145 MPH with out fear of breaking the bead etc. even spinning I still managed a 1.722 60' but I know it should do a ton better . I left at about 3000 rpm and about 20# of boost on my 10.66 run . Any advice from personal expierence with the air pressures would be appreciated . I am 4x4 by the way .

 

[TROJAN366]

I know I ran a good amount less than that with my 30x14 M&H but that is a different tire. I have a set of Mickey Thompson radials but haven't run them yet so I'm curious what people have to say.

 

[prostreeter600]

Were you running tubes or tubeless ? What pressures did you run and did it 60' well ?

 

[TROJAN366]

Were you running tubes or tubeless ? What pressures did you run and did it 60' well ?

Tubeless and it 60 footed ok but I never had much time to practice on them. Every time I put them on the truck I got kicked out of the track lol. Mike Graves has them on his crew cab now and he was having very good luck with them.

 

[prostreeter600]

https://m.youtube.com/watch?v=zImb0GDKYaI&feature=youtu.be. If you care to study the launch . I tighten up my rear coil overs to the tightest setting and adjusted my ladder bars to the lowest hole since this run . My ride tech front coil overs were already at the tightest setting . I'm due to run it again on the 28th of this month . Thought about going to a better front coil over that will help keep the front end down more but after studying the launch I don't see a lot of separation between the tire and fender on the launch

 

[prostreeter600]

Got kicked off for going too fast no cage ?

 

[PureHybrid]

12psi

That's straight from MT when I asked about the E.T. Street s/s

 

[Ne-max]

When I ran slicks on my 2wd I marked the wheels and tires with grey sharpie to check for movement. You do not want to run tubes without screws

 

[TROJAN366]

12psi

That's straight from MT when I asked about the E.T. Street s/s

That might be the lowest pressure for a radial on a 2800lb car though.....

 

[Chevy1925]

you can play with air pressure more but those front shocks are not helping you much. you need to control that bounce better

 

[PureHybrid]

That might be the lowest pressure for a radial on a 2800lb car though.....

The tires are on a 72 c10 with a 489, when I called and asked they knew all the vehicle specs.

 

[prostreeter600]

Yea I'm with Trojan 12 psi probably applies to a 2 WD race vehicle that weighs much less than my 5900# . I would shit my pants if I made a run on 12 psi .

 

[prostreeter600]

Suggestions to control the Bounce ???

 

[prostreeter600]

Ne-Max I will run lower psi and mark tire & rim

 

[PureHybrid]

Yea I'm with Trojan 12 psi probably applies to a 2 WD race vehicle that weighs much less than my 5900# . I would shit my pants if I made a run on 12 psi .

You asked for personal experience, I gave it to you.

Want my opinion? You need wider wheels

 

[prostreeter600]

Wider wheels have crossed my mind . Reason I run those 9s is because I could get them in a 5.75 backspace as well as if I went to an 18x10 with 4.5 backspace the truck won't go on the trailer due to tires sticking out too far . I didn't realize that you had personally run the MTs yourself at 4 corners with 12 psi . Gotta hand it to you then . You got more balls than me. I'll air em down to 16 PSI and do a test launch in my 100' driveway and see if the marks show any movement .

 

[TROJAN366]

I would start closer to 20 and 22 and work your way down from there.

 

[Chevy1925]

Suggestions to control the Bounce ???

a better shock that can control rebound and compression better. those ride techs were never valved to work the best at the track.

 

[prostreeter600]

Im gonna try it again with the adjustments I made as well as lower air pressure . If that doesn't net me at least in the 1.5s. I'll go to a stronger coil over -- like a Viking or similar with stronger valving .

 

[prostreeter600]

20--22 start point sounds like a good idea .