Author Topic: First test session with new setup  (Read 1716 times)

Offline tcoupekyle

  • Sr. Member
  • ****
  • Posts: 354
    • View Profile
  • Your Best Time: 4.70 1/8
  • Your Track: Houston Motorsport park
  • Your Vehicle: 225" slip joint FED
  • General Location: Houston
First test session with new setup
« on: February 12, 2023, 06:57:02 AM »
First test session with new setup.
https://photos.app.goo.gl/zxV3uKmLqvfGnJpA6

Pretty rich actually very rich. 25* timing

I think we're having issue getting lined up straight any tips?

Offline slingshot383

  • Full Member
  • ***
  • Posts: 143
    • View Profile
  • Your Best Time: 1/4 mi. 7.95 @ 168
  • Your Engine: Chrysler, alcohol, 528 cu.in.
  • Your Track: Gateway Motorsports Park (the Swamp)
  • Your Vehicle: Undercover Chassis 23T altered
Re: First test session with new setup
« Reply #1 on: February 15, 2023, 03:49:27 PM »
Looks like the car wants to pull left, except for that last video. one trick is to put an adjustable diagonal in the floor of the last bay (between midplate and rear axle). You can take that diagonal and by tightening or loosening, stop a car from pulling left or right.
Undercover 23T Altered, big block Mopar
Member of the Torque and Recoil Club

Offline tcoupekyle

  • Sr. Member
  • ****
  • Posts: 354
    • View Profile
  • Your Best Time: 4.70 1/8
  • Your Track: Houston Motorsport park
  • Your Vehicle: 225" slip joint FED
  • General Location: Houston
Re: First test session with new setup
« Reply #2 on: February 15, 2023, 06:44:23 PM »
Ooh that's a great idea. I was kinda thinking it was just my driving.
This car has several slips in the front section. I almost wonder if I should adjust the slips but idk what side to adjust.

Offline slingshot383

  • Full Member
  • ***
  • Posts: 143
    • View Profile
  • Your Best Time: 1/4 mi. 7.95 @ 168
  • Your Engine: Chrysler, alcohol, 528 cu.in.
  • Your Track: Gateway Motorsports Park (the Swamp)
  • Your Vehicle: Undercover Chassis 23T altered
Re: First test session with new setup
« Reply #3 on: February 20, 2023, 01:32:32 PM »
The slips just let the car think it is longer wheelbase than what it is, better weight transfer.  If it would have been moving right off the launch, I would suspect the wheelie bar of steering the car, the fact that it happens past the 60' mark usually means the rearend is driving the car that way.  One other thing you can do is swap sides with your slicks, if runout isn't equal that will drive the car also. If you find that is the problem, run the shorter slick 1 psi. higher. Or, pump it up to 40 psi and set it in the sun for an afternoon, that will make it grow some.
Undercover 23T Altered, big block Mopar
Member of the Torque and Recoil Club

Offline tcoupekyle

  • Sr. Member
  • ****
  • Posts: 354
    • View Profile
  • Your Best Time: 4.70 1/8
  • Your Track: Houston Motorsport park
  • Your Vehicle: 225" slip joint FED
  • General Location: Houston
Re: First test session with new setup
« Reply #4 on: February 21, 2023, 07:25:51 AM »
I checked roll out and it was 11/16 difference the taller tire being on the right side.

Offline wideopen231

  • Hero Member
  • *****
  • Posts: 1911
    • View Profile
  • Your Best Time: 1/8 3.70@ 198 1/4 5.78@245
  • Your Engine: Hemi 526 ci alcohol
  • Your Track: Piedmont
  • Your Vehicle: 225 CMC FED
  • General Location: NORTH CAROLINA
Re: First test session with new setup
« Reply #5 on: February 21, 2023, 02:46:13 PM »
If rollout differs. I was told and found true.It is easier to shrink the larger one than it is to stretch. Not say both is bad idea. To shrink, Drop ppressure tp almost nohting. Heat the tire.I use blow heater and rotate avery few minutes. Let sit. Then pump up tp pressure and measure. On a fuel car we drop pressure if car is going to be siting for long period. We also do not pump tires to stupid pressures for loading either since it will stretch rollout some.  All of that said it is just another approach and may or may not work better for you.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline lake_harley

  • Sr. Member
  • ****
  • Posts: 262
    • View Profile
  • Your Best Time: 7.06 @99.58 - 1/8 mi.
  • Your Engine: Carbureted, gas mild 305 Chevy
  • Your Track: Jeffers Motorsports Park - Sikeston, MO
  • Your Vehicle: 145" FED
  • General Location: SE Missouri
Re: First test session with new setup
« Reply #6 on: February 21, 2023, 07:05:02 PM »
Having some background in circle track racing, I'd think 11/16" would certainly tend to turn the car of you're trying to go straight.....especially with a really narrow rearend like a dragster.

Lynn