Team Sherry's Suspension issues

Here is a video of team Sherry that Becca got. The car is still rolling over on the right rear hard.

We raised the wheelie bars because we thought it was unloading the car. We also adjusted the shocks, and made a timing adjustment.

It still looks to me like the wheelie bars are unloading it , you can hear the tires slip just as it sets the front end down rather quickly. I am afraid if the wheelie bars are raised higher the front end will still go higher, might be time for a 4 link adjustment or front strut adjustment. I am also wondering if there is some slack in the anti roll bar causing the rolling over.

I did not include the et I figured Keith can tell them if he wants. Nick might want to add another kit just for insurance lol

Dilligas needs to look the video over and give his opinion.

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I don't know if this will help or not guys, but here is how I adjusted my anti roll bar, I have the double adjustable. I have zero body roll, but it's still getting up on the wheelie bars a little bit just not as much now. The next time we go I'm going to raise them a little more and see if that helps. If not, another adjustment to soften the hit a little.

Single Sway Bar: Check your tire pressure and ensure that each tire has the same pressure. Jack the front of your vehicle up until the front wheels just start to come off the ground. Ensure that the jack is dead center on the front cross member. Measure the lower corner of both the Driver and Passenger door jam or the top of the wheel well opening (centered on the wheel). You will be looking for the Passenger side (rear wheel well) to be about 1/8” lower than the Drivers side. Adjust the passenger side sway bar link to accomplish this. Tighten the jam nuts and recheck.

Double Sway Bar: Check your tire pressure and ensure that each tire has the same pressure. Jack the front of your vehicle up until the front wheels just start to come off the ground. Ensure that the jack is dead center on the front cross member. Disconnect the upper heim joint on the passenger side inner sway bar. Measure the lower corner of both the Driver and Passenger door jam or the top of the wheel well opening (centered on the wheel). You will need to lengthen or shorten the passenger side link on the outer sway bar first. You will be wanting the Passenger side to be 1/8” lower than the driver side. Tighten the jam nuts on the outer sway bar. Reconnect the heim joint to the inner sway bar arm. Mark the link with a marker, and shorten the link 1 ½ turns. Tighten the jam nuts on the inner sway bar.

Its kinda hard to explain Coug. It launches pretty straight but its like it tries to torque over to the right. It's burrying the passager side slick up in the wheel tub kinda like the chassis is twisting. That said the car has NEVER had and preload in the roll bar and it always lauched straight. I'm gonna play with the front struts a little next time out and see where they are for sure. After watching the video about twenty times, I'm kinda leaning toward something being goofy with the struts. Maybe a got a bad one?? Any simple tests to check while they're one the car? They are both equal as I checked them after I got up this am. Keep coming with tips and advice, I'll check whatever I got to to line this baby out. This suspension stuff is a huge learning curve for us and I learn a little more every time out. I appreciate all the help guys and gals, this is THE BEST FAMILY to be a member of!!! THANK YOU VERY MUCH!!



Boo Boo

If its twisting the rear that bad it most likely needs a suspension tweak as Coug mentioned, I'd try and get as much out of it that way before preloading the anti-roll,,,,,which isnt a bad thing. Like said the anti roll needs no slop in any of the joints etc.

I have watched Keith's video several times today in slo mo and full speed. I think the # 1 problem is the bottom 4 link bar is too low overall for his power level and cog. It's just yanking the front end up to aggressively for a 4 link car and the top bar is in the second hole so it is a relatively "slow" setting.

In slow mo you can see the left wheelie bar hits first , we set it a 1/2" higher than the right after his first pass. Anyway after the left smacks the track it pops back up and then the right hits the track and does the same thing and they start bobbing back and forth.

They are spring loaded so I am suspecting this is causing a quick back and forth bobbing effect at the rear end housing. I am just wondering if this is causing the car to porpoise from side to side on the tire sidewalls. This would also cause the 4 brackets to move rapidly to differnt heights even if the anti roll bar is not flexing or has slack in it. The front end is in the air so there is no effect from front springs after the tires leave the ground.

It looks like it already has this going on before the front tires come up maybe when both front tires leave the ground the torque just lays the car over on the right rear sidewall from the added action already going on . Its definitely weird looking when it comes off the bars because they are level until the front end just about touches the track. There is not that much movement between the quarter panel and the left tire though.

Damn, for some reason I still can't view any videos on photobucket......not even the videos in my own 'bucket account. Can you post the video on youtube?

If the car is launching to the right a little and it's a preload problem caused by the 4-link, the top right (passenger side) link bar needs to be shortened (not lengthened) some amount to drive the car back toward center. If it's an intermittent problem where one pass it's straight & the next it's to the right (changing pass to pass to pass) something might be bent, loose, or as mentioned possible slack somewhere.

However, what might look to be "slack" in the anti-roll links (easy to rattle the rod-ends back & forth) is to be expected if the anti-roll is truly setup "neutral" with the driver weight in the car. But a ton of slack where the arms attach to the anti-roll torsion bar/tube is not something you want. Slack at the arm/torsion bar attachment point will only get worse & worse as the through-bolt design egg-shapes the holes (and-or the spline design loosens the tooth engagement) over time.

Did you guys mess with adding air pressure pass to pass to see if it helped lessen the right sidewall collapse & to find the max air pressure where it starts to free-spin?

Randy sent me the video (thanks KY) and there's a few strange things going on during the launch.

First off do you guy's think that haze coming out of the right side of the car is tire smoke/tire rub or is that engine smoke (rich)? Like Randy said earlier there isn't really a lot of separation at the initial hit. What little separation there is starts out kinda quick, but looses speed quickly. It doesn't really look to be a hard pull/drive to the right as the launch is happening, but more of a slow right drift. I can't really tell if the roll over is more of an anti-roll problem, or just the right tire over winding/collapsing the sidewall from low air pressure. Sometimes on a "roll over" launch (depending on the angle of video or pics) you can see if the housing is still parallel with the body (an over winding sidewall) or the housing & body are at two different angles (an anti-roll problem).

I get the impression that there is quite a gap in time between the rear suspension's initial hit separation action, and the nose finally starting to lift the tires out of the beams and weight transfer getting under way. At first I thought that might have been from excessive tire rotation at the hit. But looking at it some more it looks like there's only about a 1/2 rotation before the nose starts to lift, and by 1 full rotation the front tires are up & out of the beams, so that's not too bad. It's not a dead hook, but it's also not a freewheeling "zing" either.


So at this point it's probably a good idea to check..........

Where the I/C height/length is at currently, where the shock/strut extension valving is set at, are the shock/struts dead, & look for any slack/bent/broken/loose/backed off components.

I gonna give it a good look over Dave. Thank you VERY much for the input, it is much appreciated!! The last pass, we adjusted the rear shocks to 3 from full soft and the car picked up with the only other change being a 200rpm increase on the two step for the leave. It only 60 footed 1.387 so its nowhere close to where it should be. Gonna keep after it and not let it get the better of us. I'll keep ya'll updated on the findings or next time out, thanks again ya'll!!!!!


Boo Boo

stangr8cr wrote:we adjusted the rear shocks to 3 from full soft and the car picked up......

You might want to get Bill's opinion on this too but in my opinion three clicks from full loose/soft on the rear extension valving sounds real damn loose to me........but it does kinda help point to something.

If the initial separation speed is still kinda slow/lazy even with a rear extension valving set that close to full loose, and the car still responded positively to that loose a extension setting, that does seem to say that the I/C might be too long/low, (possibly out past the 60" range)

Dave his shocks were set on 7 or 8 clicks and it was very stiff. I even had Blake come over and feel of it before we moved it . I think it has promastar shocks the replacement for the old Hal brand whatever they are called now. . I have a set of them and the settings do not even seem consistent from shock to shock if you check them individually out of the car. He definitively needs some double adjustable shocks.

Dave even after watching more it looks like the shocks are bottoming out on the compression stroke to me.

Keith did you flash the converter yet ? It even looks like it gets a power surge as it moves out off the line.

Strange has good shocks for the $$$$ http://www.strangeengineering.net/catalog/index.html

DILLIGASDAVE wrote:

stangr8cr wrote:we adjusted the rear shocks to 3 from full soft and the car picked up......

You might want to get Bill's opinion on this too but in my opinion three clicks from full loose/soft on the rear extension valving sounds real damn loose to me........but it does kinda help point to something.

If the initial separation speed is still kinda slow/lazy even with a rear extension valving set that close to full loose, and the car still responded positively to that loose a extension setting, that does seem to say that the I/C might be too long/low, (possibly out past the 60" range)

Dave our cars are almost identical in every way, but my is ladder bar and his is 4 linkk. Mine is way softer in the rear tnan his . 110 lb spring vs. 135. Mine 1.26 60's and his 1.36-1.38. just some info for you.

KY JELLY wrote:Dave even after watching more it looks like the shocks are bottoming out on the compression stroke to me.

Well, bottoming one or both rear shocks (stacking the shock snubbers) during the launch's recovery period (as the car fights the wheelie bars when the wheels are in the air and re-compresses the shocks a given amount) could definitely screw with things & cause some problems.

Stack/bottom-out the shocks and the sprung suspension is basically no longer "sprung" (for a given amount of time) at which point the sidewalls are forced into added work doing the spring & shock's job too. This could partly explain the sidewall spring-bounce.

Dave, I spoke with Bill last evening and I'm very confident we got this deal licked now. I/C was WAY too far out and too low. Suspension limiters on the front of the car will help a bunch, and the wheelie bars need to be adjusted because the right side wheelie bar is hitting the frame under the car. They will be adjusted and I'll paint the frame where it has hit and keep a close eye on it till the touching is adjusted out. I'll be bringing the I/C back to 50" out and 9" up from EIGHTY SIX out! and 5 1/2" up. The front struts are around the middle and I'm going to stiffen them up a couple more clicks as well. Thanks again for all the advice and help and I'll let ya'll know what she does next time out.



Boo Boo

stangr8cr wrote:I'll be bringing the I/C back to 50" out and 9" up from EIGHTY SIX out! and 5 1/2" up.

Yea, I was betting the I/C was way the phuck out there if the car was liking the rear shock extension valving set on the real loose side. The 45' to 50" range does sound like a better I/C starting point. And it should allow you to tighten up the rear shock valving back up to around the 5/6 click area giving you a shock starting point with more room to adjust either direction a bunch before reaching the full loose/tight area again.

again Dave ...excellent info

DILLIGASDAVE wrote:

KY JELLY wrote:Dave even after watching more it looks like the shocks are bottoming out on the compression stroke to me.

Well, bottoming one or both rear shocks (stacking the shock snubbers) during the launch's recovery period (as the car fights the wheelie bars when the wheels are in the air and re-compresses the shocks a given amount) could definitely screw with things & cause some problems.

Stack/bottom-out the shocks and the sprung suspension is basically no longer "sprung" (for a given amount of time) at which point the sidewalls are forced into added work doing the spring & shock's job too. This could partly explain the sidewall spring-bounce.

My 2C

What rear coil spring is being used and maybe a longer real coil spring or sligtly heavier spring? I don't know but reading the above that's what I see? Going off Jon's comment (no longer "sprung")

One question why does Keith's and Damon car's have to pull the front end higher than Blake's car which has a ladder bars.

KY JELLY wrote:One question why does Keith's and Damon car's have to pull the front end higher than Blake's car which has a ladder bars.

x2 ..... i only pull the wheels 6" max

KY JELLY wrote:One question why does Keith's and Damon car's have to pull the front end higher than Blake's car which has a ladder bars.

Mine does because of the way the 4-link is setup: the bottom bar needs to go down one more hole in the front however I don't have any more holes

My junk does not pull the wheels very far up either, I set the motor pretty low in it and I figure this is the reason. I don't have the front weight bias like Blake does, so thats not the issue.

D. Sea wrote:

KY JELLY wrote:One question why does Keith's and Damon car's have to pull the front end higher than Blake's car which has a ladder bars.

Mine does because of the way the 4-link is setup: the bottom bar needs to go down one more hole in the front however I don't have any more holes

raise it up in the back and see what happens inquiring minds want to know

Something to think about your car sets lower than Keith's is your ic higher than his ?

richter69 wrote:My junk does not pull the wheels very far up either, I set the motor pretty low in it and I figure this is the reason. I don't have the front weight bias like Blake does, so thats not the issue.

Weight bias I can pick my car up completely off the ground with 1 hand in the front with the engine out

Mr. Evans and Mr. Mayfield powered!


Boo Boo

KY JELLY wrote:

D. Sea wrote:

KY JELLY wrote:One question why does Keith's and Damon car's have to pull the front end higher than Blake's car which has a ladder bars.

Mine does because of the way the 4-link is setup: the bottom bar needs to go down one more hole in the front however I don't have any more holes

raise it up in the back and see what happens inquiring minds want to know

Something to think about your car sets lower than Keith's is your ic higher than his ?

Randy,

What I need to do is add some metal to the front bracket and make another hole for the front bottom rod ends. The back bottom rod ends are already in the top hole. It seems that this 4-link brackets are more for a full tubed car that sits lower. I'd say that my IC is higher than Keiths but I'd need to measure again to make sure.