Drag Racing Tech
Sponsored by:
Sponsored by:

Launch Video need help

Old 10-12-2009, 06:34 PM
  #1  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default Launch Video need help

http://www.youtube.com/watch?v=m1qheDMgTwE

I've slowed the video down so you can see it in slow motion. This is a 1.70 60ft

It looks like when I let the clutch go, the tire flatens and then bounces back up harsh, causing the car to spin, then it hooks and goes.

Is the suspension set to hit the tires to hard? Causing it to unload....

Or are the stock rear shocks just not able to control the launch?


Lower control arms are in 1 hole up from the bottom - MWC 9" with 4 holes.

Torque arm is 1 hole up from the bottom.

Pinion Angle is 2.0*
Old 10-12-2009, 10:44 PM
  #2  
11 Second Club
iTrader: (37)
 
Mikey 97Z M6's Avatar
 
Join Date: Mar 2004
Location: Vancouver, WA
Posts: 2,046
Likes: 0
Received 2 Likes on 2 Posts

Default

I've been watching my vids in slow motion the last couple weeks, and it's doing the exact same thing. My car has Comp Engineering 3-way adjustables on the back, so I put them on 70/30 (hard compression, loose extension, ) and it seemed to help with the "snapping". It still does it but it's not as violent and doesn't seem to unload the tires as quickly. You could try moving the front of the t/a up one hole so that it doesn't hit quite as hard.

What's the angle of your LCA's? If your car isn't lowered, you might try the stock LCA setting.

Mike
Old 10-13-2009, 10:06 PM
  #3  
10 Second Club
iTrader: (1)
 
1BADAIR's Avatar
 
Join Date: Jan 2003
Location: oxford, Michigan
Posts: 1,902
Likes: 0
Received 1 Like on 1 Post

Default

pm sent
Old 10-18-2009, 04:16 PM
  #4  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default

Moving the lower control arm helped.

No more traction issues - just bogging issues

Got my best today - 12.003@114.79 - no 11's for me.
Old 10-18-2009, 10:11 PM
  #5  
TECH Addict
iTrader: (83)
 
Gray86hatch's Avatar
 
Join Date: Sep 2009
Location: Battle Creek Mi
Posts: 2,388
Likes: 0
Received 3 Likes on 3 Posts

Default

Get a good set of shocks they are the most important part of getting the car to leave. More tire pressure.
Take some bite out of the car. Way to agressive.

Tim
Old 10-19-2009, 12:40 AM
  #6  
On The Tree
iTrader: (3)
 
Elcaballoloco's Avatar
 
Join Date: Apr 2007
Location: Colorado Springs, CO
Posts: 189
Likes: 0
Received 0 Likes on 0 Posts
Default

Side question... what kind of camera was used here with what program to slow it down?
Old 10-19-2009, 06:44 AM
  #7  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default

Sony Handycam and Apple Imovie.

Rear shocks are on the list for next year. As is more power so I can get rid of the bog.
Old 10-19-2009, 05:14 PM
  #8  
11 Second Club
iTrader: (16)
 
SuperSlow02's Avatar
 
Join Date: Feb 2006
Location: Cape Girardeau, MO
Posts: 1,865
Likes: 0
Received 0 Likes on 0 Posts
Default

so....it looks like you carried the front left after the initial launch
Old 10-19-2009, 05:28 PM
  #9  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default

Nope

At least it hooks now - it's time to add power to get rid of the bog
Old 10-19-2009, 05:46 PM
  #10  
9 Second Club
iTrader: (2)
 
N2RACINGLS1's's Avatar
 
Join Date: Dec 2005
Location: East, TN.
Posts: 1,194
Likes: 0
Received 2 Likes on 2 Posts

Default

Is that a stiff sidewall slick? If not that could be some of the problem!

N2
Old 10-19-2009, 06:12 PM
  #11  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default

Nope

bias ET Street 26x11.5

The traction problem is fixed!


Moving the lower control arms back to the stock hole worked.
Old 10-19-2009, 09:25 PM
  #12  
9 Second Club
iTrader: (2)
 
N2RACINGLS1's's Avatar
 
Join Date: Dec 2005
Location: East, TN.
Posts: 1,194
Likes: 0
Received 2 Likes on 2 Posts

Default

When you have a 6 spd in a heavy F-body you need a stiff sidewall slick to get the full benefit of dropping the clutch and improving you 60 foot which will then improve your entire run.

Call M/T up and they will tell you that you need to run a stiff sidewall on your car and it will help! Also when you switch to a true slick and take off the ET Streets you will be happy because you will no longer be in the 12 second club! Try M/T 26X10X15 ET Drags!

Good luck and be safe!

N2
Old 10-19-2009, 10:03 PM
  #13  
TECH Addict
iTrader: (83)
 
Gray86hatch's Avatar
 
Join Date: Sep 2009
Location: Battle Creek Mi
Posts: 2,388
Likes: 0
Received 3 Likes on 3 Posts

Default

Adding tubes will help. But the pressure is way to low and it hits the tire way to hard. With good shocks it will hold the tire down but on this car I don't see the shock being able to help it.

Tim
Old 10-19-2009, 10:08 PM
  #14  
10 Second Club
iTrader: (1)
 
1BADAIR's Avatar
 
Join Date: Jan 2003
Location: oxford, Michigan
Posts: 1,902
Likes: 0
Received 1 Like on 1 Post

Default

where did my post go?


The tires are working fine now. The car dead hooks and bogs since the lca adjustment
Old 10-19-2009, 10:29 PM
  #15  
TECH Addict
iTrader: (83)
 
Gray86hatch's Avatar
 
Join Date: Sep 2009
Location: Battle Creek Mi
Posts: 2,388
Likes: 0
Received 3 Likes on 3 Posts

Default

It is hooking the bog will go away with taking some hit out of the suspension. Upping tire pressure and controling the axle. Adding more power is not going to fix the issue you have in the video. The wheel almost hits the track. You can't get a car to leave when it is doing that.

Tim
Old 10-19-2009, 10:46 PM
  #16  
10 Second Club
iTrader: (1)
 
1BADAIR's Avatar
 
Join Date: Jan 2003
Location: oxford, Michigan
Posts: 1,902
Likes: 0
Received 1 Like on 1 Post

Default

here is a vid with the LCA moved up. spun this run because he was adding tire pressure to control the bog
http://www.youtube.com/user/nocooler.../1/TiFqGqEFi_w
Old 10-20-2009, 06:44 AM
  #17  
11 Second Club
Thread Starter
iTrader: (5)
 
nocooler's Avatar
 
Join Date: Apr 2007
Location: Mid Michigan
Posts: 605
Received 62 Likes on 40 Posts

Default

Originally Posted by 1BADAIR
where did my post go?


The tires are working fine now. The car dead hooks and bogs since the lca adjustment
Thanks.....

Thank you everyone for there input. The car dead hooks now from a 6350rpm launch with the tires @ 14psi.

I can upload some other videos to show how the suspension works now......


Thread Tools
Search this Thread

All times are GMT -5. The time now is 04:14 PM.