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Slowing cars reaction time

19K views 52 replies 29 participants last post by  COOK E  
#1 ·
I'm having a problem slowing my car reaction time so I can leave on the flash of the last yellow bulb.
Currently I have to leave somewhere between the yellow and the green.


I have a 93 mustang with a 550 horse SBF and a powerglide with a pro brake, 180 gear, 4.30 rear gear and 28" tall rear tires, 26" tall moroso front tires.
Rear suspension is all Team Z. Car weight with me is 2700lbs.

I have the front suspension totally loose.
Launch at 4000 RPM. = 1.43 60' time.
Long Biondo trans brake button.
Front tire pressure 35psi.
Rear tire pressure 10psi.

What else can I do to slow it down?
Will staggering my front wheels help?

Thanks
Ken
 
#49 ·
Or you can eat 2 burgers and two dogs right cumminatya.... lol Oh sorry that just slows down the driver....
 
#4 ·
Where are you staging at, deep or shallow? If I stage too deep, I'll bulb. If I just tickle the second beam, it's ok.
 
#7 · (Edited)
How much red are you going? Is by a consistant amount? Is the track and beams consistant(even from lane to lane)?

Like cumminatya said there are countless ways of impacting R/Ts. Taller front tire, tire pressure, staggering wheels, anti-squat, launch RPM and driver are all changing the R/T.

We are fighting red lights in Scotty Bs car now on a 500 pro tree with a stick car. We changed front tires added ballast in rear to firm up some inconsistancy we saw on film and tested, made 4 passes. RT's were .003, .008, .020, .001 . Went to another track and R/Ts were all over the place (spread of .120 overall from .030 red to .087 green) and others noticed lane to lane was off also with one being tight. Red in right was green in left. Letting some air out in front helped but still was inconsistent. Maybe it's car, track or the driver having a bad day. We will see in BG this weekend.
 
#9 · (Edited)
Also what type of racing is it? Heads up, bracket, or index? I assume since you said last amber it's full tree and so assuming once again bracket? A lot of things you do to car set-up will also affect ET to some extent.
 
#11 ·
How much front suspension travel? Get as much as you can. Get 28" tall front tires. Hell, I run the MT 29" on my wagon. Very tight fit on turns, but I'm still trying to find about .08 second. How much air in front tires? You could get some with just dropping your current tires.
 
#16 ·
I was having the same problem... At Martin MI.. I was .003 red .. 004 red...004 red again....011 red.... 018 red.... I didn't do much racing that weekend..... I put a bigger tire on the front... adjusted my front and rear shocks to a harder setting.... dropped my rpm by 700 . I use a terminator tb switch and had all the shims out, now I have 3 shims in and cutting .010 to .020 green lights... now i can adjust with just the shims.
 
#39 ·
Lose the pro brake. Sportsman brake for sportsman tree. I'd bet your not anticipating. With my pro brake , reaction time is .02 to .06 green on a .400 pro tree. On a sportsman bracket tree it is .03 to .05 red leaving on last amber flash. Sportsman tree is one tenth slower so you do the math. I've asked the same question you did. It will be tough without changing the brake. I mostly heads up race so I won't be changing mine.