Evaluate Launch
 

At track this weekend playing w/ QA1 front coilovers/dbl adjust shocks.
Swapped to this combo to better control front end on launch (bouncing) and be able to better adjust front end height.
Started out w/ 4 clicks extension and 12 compression. We ended up getting best run w/ front shock adjusted at 8 extension and 8 compression. Rear shocks are calverts adjusted 4 clicks (i think they adjust up to 9. What they have been set for years n car)
W/ old 90/10 shocks and trick springs I pulled front end up higher but had identical 60' and 1/8 times.
Watching video i think I could hit rear tire a little harder (appears to spin) and car still appears to bounce up after initial launch.
30x9 tire and 4:56 gear.
Link below is best pass that gave 1.38 60' and 6.38 1/8. Video in slow motion, but I wish quality was better. I think some definition was lost transferring from phone to computer.
https://youtu.be/6kcNrEytF_g

NOt an expert...my observation....on the hit the front comes up and drops quickly. I think too quickly.

May give the front end more freedom to come up and settle down further out.

I agree also.

Almost looks like it's 'porpoising' which would need different spring rates.
Also could be the rear shock topping out?
Have enough shock travel front and back?

Could need a different launch RPM to make it work the way it is also?

:confused:

I'll check rear shock length.
Front springs 300lbs a lot stiffer than my 200lb big springs but they had car sit too low. Don't think I want stiffer springs.
I was thinking go up in compression to keep front up longer which might take out bounce.
I launch at 3000. Convert flashes around 4800.
THanks for input.

I cant tell , what's happening in the back, if it's getting any seperation back there, it is spinning for sure, have u made sure everything moves freely in back nothing over tightened, shackles move free and easy? Still have stock shackle set up? Stock location in back for shocks?

Your spinning just off from the line, that's why the nose goes up and then drops fast.

Paint a big white triangle on the side of your slick with its point starting at the rim, and the next time you look at a video of your lunch you will see it much better.

What does the car weigh, and do you have stiff side wall slicks?

Stiff sidewall, calvert leafs w stock location shackles,
Weighs 3165 w driver

Sorta interested in seeing what car will do if I can get suspension dialed in, esp w/ current 60' and 1/8 mile results spinning/bouncing in summer heat. I sent video to calvert and qa1

It looks to me like your front shocks are way too soft. My A-body did the same thing with the shocks set on soft. I firmed them up as much as I could and my problem went away. A friend of mine believes in soft front shocks. His car actually does two wheel stands from the up and down motion of the front end.

Omt - soft on compression? They are set 8 but can go up to 16 or 18

I checked rear shackles - loose, rear shock has plenty travel - 2.25 shaft showing compressed, 5.75 extended suspension dropped and 8.5 max extended.

Primarily soft on extension. I set mine as stiff as possible, and limited my front end travel to 4-5".

Did u unhook shocks and see if suspension drops any further? It is spinning i see that, its just hard to see how much separation your getting and rear fender well
I would tighten up the front or drop it some more for more travel, u need more travel longer out before it tops out. U may actually have to loosen rear shocks some, Just have to keep trying ****, the best thing u can do is put a gopro under the car like i did so you can see what its doing!

Rear shocks have plenty travel, not restricting leafs. Calvert recommend start full loose on front unless it wheelstands then tighten, and loosen rear shocks (1-3 clicks, i'm at 4, tightest is 9).
I think we're going wrong way with 8/8 setting on dbl adjust.
Looks like rain fri for tnt, limited test time for sat race.

Full loose is fine up front "IF" you have the front end travel and not top out too quick upsetting the rear. The front and rear have to work together, Do U have the original video u could send me?

Here's mine on the 24th with the Drag Radials, watch the front end and how much longer my front end is on the ground on take off, using that extra travel to keep weight moving towards back. You can slow it down in the settings when u watch it.

https://youtu.be/n7qPfeg7S3E

Only have video texted from friend.
Not sure quality is that much better. I can forward it send me email or cell#

To me it looks like you need more travel in the front suspension.

GT.

I agree on more front end travel. My 6.0/ 10.90 63 Tempest did that for years and I battled it. My Strange struts had 2 1/2" travel and I changed springs 4 times but couldn't cure it. I moved the four link everywhere. I installed Santhuffs this winter and problem is gone. More travel and much more control. They matched the springs to my set up. I wish I had spend that money years ago and I would have had a lot more fun/luck with my car. My old set up would top out the travel then yank the front end back down and I would fight a spin. Now it's smooth as glass.

More front end travel, in conjunction with some experimentation on tighter rebound settings. Think more travel at a slower rate, instead of less, quickly.