Thread: first time out 9.89@144

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I don't believe static binding would be an issue, that would be too obvious and way too easy!!!!!! Leaf springs have a tendency to wrap up when the car launches, then unwrap at a very inopportune time, often resulting in unloading the chassis.... The suspension bind would occur when the spring is loaded and wrapped up on launch..... I like to video the car looking at the right rear corner as it proceeds down the track, this will usually give a good indication of the suspension movement, or lack of it.

sounds like the shocks are doing their job. I guess it's just guesswork without a really good video of the launch charachteristics. Identical parts sometimes means very little... Old springs with worn out bushings out of a 100,000 mile car that spent it's life traversing washboard roads will react much differently then the one's that were on Grandma's car and only went to church and back on smoothly paved streets. Even brand new parts right out of the box are seldom identical, depends on the level of quality control when they were made..... As I said earlier, the only leaf spring setup I ever had work good was mono-leafs with housing floaters and ladder bars.... So little tuneablilty in leafs vs. coilovers......

Originally Posted by Dave Severson

I don't believe static binding would be an issue, that would be too obvious and way too easy!!!!!! Leaf springs have a tendency to wrap up when the car launches, then unwrap at a very inopportune time, often resulting in unloading the chassis.... The suspension bind would occur when the spring is loaded and wrapped up on launch..... I like to video the car looking at the right rear corner as it proceeds down the track, this will usually give a good indication of the suspension movement, or lack of it.

sounds like the shocks are doing their job. I guess it's just guesswork without a really good video of the launch charachteristics. Identical parts sometimes means very little... Old springs with worn out bushings out of a 100,000 mile car that spent it's life traversing washboard roads will react much differently then the one's that were on Grandma's car and only went to church and back on smoothly paved streets. Even brand new parts right out of the box are seldom identical, depends on the level of quality control when they were made..... As I said earlier, the only leaf spring setup I ever had work good was mono-leafs with housing floaters and ladder bars.... So little tuneablilty in leafs vs. coilovers......

Dave,your making alot of sense.Weak springs and/or wrong shock,caltrak short ,,,,launch then loose of traction,does this not mean at launch/shocking the suspension,works some but is being over powered after it reacts? Too loose.

ljuksufdfu

hey guys i found why the front doesn't come up!! there's little rubber stops on the frame rails for the upper control arms. took them out and we get 6" know. i hope it helps the weight tranfer.

that helps on mine

Originally Posted by 500caddy

hey guys i found why the front doesn't come up!! there's little rubber stops on the frame rails for the upper control arms. took them out and we get 6" know. i hope it helps the weight tranfer.

Should help a bunch!!!!

If it ends up being too much, put on some travel limiters. Sometimes an extreme amount of frontal lift eats up a lot of the torque lifting the front instead of planting the rear tires. A compromise on the amount of lift can sometimes really help the forward bite!!!!!

dave we did some driveway launchs and it will pull the tire about 3ft know!!!!! hole chit i would have never thought something that little would make that big of a differents. his driveway is 400ft long with a very nice cement launch pad.. i looked on my car and the chassis guy put some type of limiter for the upper control arms on it. so we are making a set. so if i got this right dave. if the car is pulling to big a wheelie adjust the limiter so it stops or just not so high.. what is the right hight for a wheelie?? my car has wheelie bars so i never real had to deal with this. i thought building a copy of my car would be easy to do.i found out fast just like two of the same engines they don't always work or run the same..

I always felt it was best to just get the tires up, maybe an inch but ideally just barely making contact with the pavement.... Would seem anything more is just wasting torque that could best be applied to the rear in the form of forward bite.... The trick is to get it to lift just the right height...your 60' times will be the indicator of what the car likes best. You could also come up a degree on the pinion angle to bring it to 3 degrees pinion down and see what that does to it. Does sound like it will need some wheelie bars on the back. We used to play with the spring type bars, wound up selling that car before we ever reached any definitive conclusion on what was best...so many other variable on 60' times, especially on a cheap track where the launch pad is never the same on any two passes. But hey, sometimes it's a trip to put the wheelie bars in the high hole and let her buck!!!!!

well dave were going to put the screws to it this weekend and see. no wheelie bars but she might just buck as you would say. we set the car up as follows. frontend lifts 5.5" like denny and nitro,dave said to. i put the pinion angle at 3degs, caltrac are preloaded 1full turn pass side a 1/4 turn driver side per caltrac, ride height is only 1" lower in the front know. when you jack it up it will go 3.5" higher before it pulls the front tires off the gound.that makes the front go up past level about 2" that should help put more weight over the rear tires. if you guy read this and see something please tell me or some input on what you would do feel free i'm all ears..

Should be a good starting point.... If it pulls left or right, play with the preload.

thanks dave i should have better pics when i come home..and some video

I think that will help alot ,above all be safe and the most important thing of alll.......................have FUN!!!!!!

update. went to lapeer dragway and the car will pull a 1ft wheelie footbraking it. the trans brake just blows the tires off. the front is coming up alot better but still unloading the rear tires after 10ft. tried adjusting rear shocks with no real differents. the rear seems to be way to stiff and bounces down track but if you get it to stop bouncing down track it wont leave right. best 60ft went from 1.52 last week to 1.41 9.7@150mph with the frontend mods. i'm lost at this point. i think the front is good but the rear has me pulling my hair out. running 9.7s is making me sick when it should run 9.0 on motor. please!!!!!!!! more input guys thanks for the input on the frontend stuff.

Is the rear end suspension still stiff leaving the line?

Originally Posted by 500caddy

update. went to lapeer dragway and the car will pull a 1ft wheelie footbraking it. the trans brake just blows the tires off. the front is coming up alot better but still unloading the rear tires after 10ft. tried adjusting rear shocks with no real differents. the rear seems to be way to stiff and bounces down track but if you get it to stop bouncing down track it wont leave right. best 60ft went from 1.52 last week to 1.41 9.7@150mph with the frontend mods. i'm lost at this point. i think the front is good but the rear has me pulling my hair out. running 9.7s is making me sick when it should run 9.0 on motor. please!!!!!!!! more input guys thanks for the input on the frontend stuff.

the left lane at lapeer dragway the flint guys like that track is bumpy is all hell i seen cars unload and jump all over why not go to ubly better track?? and this comming week. i just may show up.. bay city rollers drag is that week end