Lowest Safe air pressures for drag racing on Drag Radials

Evan@InglewoodTrans

yerp
Vendor/Sponsor
Aug 5, 2010
3,118
65
48
40
Western MA
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.

They went 147 mph this year. He's cut 1.50 60's they are still working great.
 

gmduramax

Shits broke
Jun 12, 2008
4,072
248
63
Nor cal
Soften your shocks. How much travel does your rear end have? Almost looks like it hit the bump stops and pulled the front end. Either way you want your traction bars set to make the rear end rise
 

prostreeter600

Street rodder
Jul 18, 2010
894
7
18
Dallas Tx
Noted on the traction bars , and my shock adjustments in the rear were set in the middle . I tighten them all the way so that it's harder to compress them . I moved ladder bars to bottom hole in the front .
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,495
476
83
Central OH
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 .

Haven't ran them on all 4, just the rear
 

prostreeter600

Street rodder
Jul 18, 2010
894
7
18
Dallas Tx
I was agreeing with Trojan . No pun intended . Just trying to get better 60' times to get a better 1/4 time slip and hopefully up my MPH as well .
 

prostreeter600

Street rodder
Jul 18, 2010
894
7
18
Dallas Tx
LMAO .. I had Mark update my tunes since that run because it ran so clean . I had him out more fuel to it . If I can get it to 60' better it should go high 9s on fuel only . Then I have spray for it too .
 

TROJAN366

Gold Rush
Jan 13, 2012
2,474
1
38
MASS
LMAO .. I had Mark update my tunes since that run because it ran so clean . I had him out more fuel to it . If I can get it to 60' better it should go high 9s on fuel only . Then I have spray for it too .
My truck has a bunch of goodies since my last pass. I just can't find time to get it to the track!
 

Harbin_22

Active member
Dec 4, 2010
3,858
7
38
Southern Indiana
I run 28-30 front and 20-22 rear on the 30x14. Someone correct me if I'm wrong, but moving your bars down would be putting more lift to the front of the truck.
 

Dan@PPE

Diesel Enthusiast
Aug 8, 2006
2,570
0
36
So Cal.
I run 28-30 front and 20-22 rear on the 30x14. Someone correct me if I'm wrong, but moving your bars down would be putting more lift to the front of the truck.

What is your 60's like? you run a bit more air than I do, although your truck is a bit heavier than mine (I think)
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,681
5,835
113
Phoenix Az
I run 28-30 front and 20-22 rear on the 30x14. Someone correct me if I'm wrong, but moving your bars down would be putting more lift to the front of the truck.

moving the bars down amplifies the pressure put on the spring pack in the rear end. like adding more spring rate to a suspension setup. it can add more front end lift depending on how the shocks front and rear are set up. basically, it should make the rear tires hit/bite harder if everything works as it should.
 

prostreeter600

Street rodder
Jul 18, 2010
894
7
18
Dallas Tx
Keep in mind I run ladder bars with coil overs in the rear , no leaf springs & coil overs in the front no torsion bars . As stated above moving the ladder bars to the lowest hole at the front of bar is suppose to provide the hardest hit most down force to the tires . I just made that adjustment and tightened the rear coil overs to their tightest setting . Adjustments were made in an effort to get a harder hit more down force to rear tires plus the tighter setting on coil overs is to where any weight transferred to rear all goes to the tires instead of getting absorbed in the suspension where the gap closes between top of tire and wheel opening . I plan on taking the truck to Emmis Tx on the 28th for a Fast Friday Event . I will be running lower air pressures as well , leaving tailgate, passenger seat and center console at home this time . Surely that tailgate being on and having it up increases the wind drag on the truck since I don't have a bed cover and don't want one . Hoping for 1.5s 60' and at least low 10s on fuel only . Had Mark put more fuel in tunes as well since that 10.66 was super clean .
 

prostreeter600

Street rodder
Jul 18, 2010
894
7
18
Dallas Tx
Harbin are you thinking that having the ladder bars hit harder is helping my front end come up ? Which is obviously not what you want in a 4x4 launch .