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72 Nova, Caltrac's and Splite Mono's, 10.5 tire, 600+ci, NA!
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Discussion Starter · #1 ·
I have a brand new setup .. CalTrac'd, Split Monos, dbl. adj. strange shocks.. Anti roll bar.. 72 Nova 3400lbs.... 588ci, motor only class, 10.5W .. should make 4 digit HP number. I bought a set of Comp Eng. 44" Wussy Bars... these don't have much adjustment, if any......

My question to all you High HP Leaf Springers... How high should I set my wheelie bars off the ground - for initial setting? I'd like to get the wheels up in the air of course - but not to the point where Im coming down and ruining the bottom end.. I have limiters installed up front, single adj. QA1's, and the trick moroso springs...

Let me know what you guys think a good height would be to start.. ??

As always, appreciate the comments.

Jeff
 

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I have a vega that I just put wheelie bars on. They ar 44" sping loaded. It has ladder bars and the wheelbase is @97 inches. If I set the bars at 2" does anyone know around how much the front will be off the ground? I have a race this weekend and will be trying them for the first time. There is a weight penalty for the bars, but I was over weight enough that it works fine with them. We run 1/8th track around here and my car runs 5.70s to 5.80s usually (depending on which track). I am hoping the bars will work so I can put some Nitrous on it for some grudge racing also. Any ideas would be great, Barry
 

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I just put mine on as well. I set mine to be 4" off the ground to the center bolt, that makes the bottom of the wheel about 2.5" off the ground. Keep in mind I have not tried this yet, so I don't know.

 

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I run 54" spring loaded S&W's with them currently set at 9 1/2" to the bolt centerline.

I'm still not sure how high they should be, but on the small tire car like mine, I need some wheelie, just don't want to go up towards the bumper anymore.
 

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BTW, do you know how much pinion rotation your car see's when it launches?

I remember seeing a video of Mike Thompsons car (caltrac/leaf spring) and his bars would slap the ground at the hit from the pinion rotation. I believe he had to set the bars pretty high to prevent that.
 

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No, I dont know how much the rear rotates. I guess I will have to experement. I wish I could test and tune before the race, but I suppose the 2 qualifying runs will have to do. I have to run a 28x10.5 tire so I'm sure I will need the front tires up to some degree, but as low as possible. My last race while my car was still lifting the front end my opponents had came back down and was smoking my a$$. I have the drivers bar @ 1/4" higher than the passengers (due to research on the internet). With the glide on the brake I could get 1.25 60ft and footbrake 1.28. I hope to get the same with the th350 (I have to footbrake for now). I guess I worry to much. I just have got tired of making it a few rounds and as the night progresses so do my wheelies, and I dont want to wreck the car for the little amount we run for.
 

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Ok Guys,
This will sound crazy to you. Think about it first.

Measure the distance from the ground to the wheel. Lower air pressure on both tires until they are 1/2 that diameter from ground to the wheel.

Jack up the front of the car just to the driver's side of weight center to the appx wheelie ht you are trying for.

Place the bars there and weld the brackets in place allowing some adjustment on bracket both down a little and up.

When you get done, the left wheel should be just a bit higher than the right. Go try it at the track.

2 inches from the ground will unload the rear tires on any car unless they are spring loaded and each spring loaded bar design allows a different range of movement before it binds and doesn't move anymore.


The longer from the axle the wheelie wheels are the higher from the ground they will need to be to maintain the same wheelie ht.

No one can guess accurately how much pitch rotation will occur when you launch IT will rotate though no matter what style the suspension is or how right the brackets and joints are. It will rotate much more than 2 inches for sure.

Next time to the track, just watch all the different cars wheelie bars for that quick instant hit toward the ground. Most times that is before the front end even comes up.

Ed
 

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Sounds like good advice. I guess the general rule is, there is no general rule. I will find out Saturday, if it doesnt rain, which they are calling for as of now. As long as I can make straight passes, I will learn the fine tuning eventually I'm sure.
 

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Young engines,
Likely adjusting wheelie bars is not what your first priority could be. Just by your words you need to do suspension adjusting first. Tighten up some on upward movement of the front suspension if possible and still allow a minimum of 1 inch for suspension action down track. Adjust the extension of your shocks to be tighter if that might help. Or if you move your front ladder bar pivot point or mounting bolt hole to a lower hole will get some of your tire hit out. To get smaller amount of tire hit out of it, lower the back of the car some.

Wheelie bars are a safety device that aids in suspension tuning. Not for fully controlling all wheelie conditions. If wheelie bars are slapping the track hard you have too much instant dead hook with your tires. Cars should just touch down on the wheelie bars and not with great force. I have a customer that busted three sets of wheelie bars last year. Obviously his suspension guys must be doing someting not exactly right.

Ed
 

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I'm still trying to get a handle on mine as I'd like to eventually be able to take them off. I added limiters two years ago, and upgraded the QA1 double adjustable front shocks to a pair of Afco BNC double adjustables.

Here's a video from last year with the QA1's, an earlier pass trying to learn how the car was reacting with the bars on.

http://www.qis.net/~geislert/PSI_semi.wmv

One thing I noticed is it seems as though the bars push the front down prematurely. The car used to carry the tires further out when not using the bars.

Sorry for taking the topic off subject, just thought this is something we can all learn from. There's very little info out there for setting up and tuning wheelie bars on different tire/chassis setups.
 

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I have moved my ladder bars and it helped. You are right about lowering the car. The last time I was at the track with the 28" tires it worked well, however it was at a different track than we race at and during the day. I went back to the same track with my 29" tires( I had to move up the back of the car one hole in the coilovers and it went straight for the sky). The come down boke the fan, knocked one headlight loose, and a tack weld on the bumpers. I also limit the front travel. Hopefully I will learn more as I go.
 

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DOTracer, I checked out you video, looks good! If I could get mine to do that I'd be very happy. What 60ft do you get? I run no power adder, so I have to get out fast and hope they can't get back bye on the big end.
The car has 60'd a best of 1.289, on average the 60' is in the 1.31 range footbraking, no power adders.

BTW, I flattened the headers twice after fist installing the bars. My initial mistake was having the front shock rebound too loose and it came up too fast and too hard. Once I figured out the front end needed to be much tighter, the car came around and wasn't as violent on the hit of the bars.
 

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I have a new set of shocks for the front ( the shocks on it have had a rough life from the hard come downs). They are just 3 way adjustable. I have the shocks on the front set on 90/10. I was thinking of setting the new shocks tighter to keep it from coming up so fast. I was going to wait till after this race to change them, but now I believe I'll do it before. Thanks
 

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72 Nova, Caltrac's and Splite Mono's, 10.5 tire, 600+ci, NA!
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Discussion Starter · #16 ·
I'm still trying to get a handle on mine as I'd like to eventually be able to take them off. I added limiters two years ago, and upgraded the QA1 double adjustable front shocks to a pair of Afco BNC double adjustables.

Here's a video from last year with the QA1's, an earlier pass trying to learn how the car was reacting with the bars on.

http://www.qis.net/~geislert/PSI_semi.wmv

One thing I noticed is it seems as though the bars push the front down prematurely. The car used to carry the tires further out when not using the bars.

Sorry for taking the topic off subject, just thought this is something we can all learn from. There's very little info out there for setting up and tuning wheelie bars on different tire/chassis setups.

Damn!... very nice launch. And thanks to everyone for all the comments. I agree, just gotta play with everything to get it right - everyone setup will act a bit different. My car will be like yours, small tire... relatively speaking (29.5 by 10.5W) ET Drag's... with the Caltracs.. the car needs to see some air to get all t the goodies to work correctly. I think I will set up the bars atleast 5 to 6 inches off the ground, maybe more... and leave adjustment to drop em' down if necessary. ???? We'll see. Playing with the limiters will help too with seeing too much air.

I'll get it figured it out.

Again,
Thanks.

Jeff
 

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Jeff,

We put bars on ours, 3" off ground, along with stiffining up the front shocks.........did not like it. Actually, when our car launches, our bars go UP, not down like alot of people are noticing. The car spun before even hitting the bars, it did not like the front end being stiffened.

Next time out we are putting the bars to 6", putting shocks back at 90/10 so it can launch hard and utilize the bars........we went from sitting it on the bumper to blowing off the tires.........track was awesome too so we are going back to a harder launch.

I want at least a 1' wheelstand, thats when these things seem to really work.....everybody was telling us the bars were too low at 3"...........just got to play!

Good luck and let us know how you did.........when are you getting it to the track?
 

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72 Nova, Caltrac's and Splite Mono's, 10.5 tire, 600+ci, NA!
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Discussion Starter · #18 ·
Hey Cuda..

Jeff,

We put bars on ours, 3" off ground, along with stiffining up the front shocks.........did not like it. Actually, when our car launches, our bars go UP, not down like alot of people are noticing. The car spun before even hitting the bars, it did not like the front end being stiffened.

Next time out we are putting the bars to 6", putting shocks back at 90/10 so it can launch hard and utilize the bars........we went from sitting it on the bumper to blowing off the tires.........track was awesome too so we are going back to a harder launch.

I want at least a 1' wheelstand, thats when these things seem to really work.....everybody was telling us the bars were too low at 3"...........just got to play!

Good luck and let us know how you did.........when are you getting it to the track?

Hey there.. get your beast back together?

Yeah, all I've heard is that with the smaller tire and caltrack setup - I'll want to let it take the nose skyward a bit to get it all to work properly..... just hope I can find the sweet spot without too much effort.

I will probably set the bars about 4 to 5 inches to start... medium on compression and rebound in the rear shocks.. and probably go 90/10 on the fronts... give myself 3 inches or so on the limiters? and lett'er go!

I just got the motor up to the chassis guy... just finished. chassis is almost complete.. now, I just need to get up there and spend a day wiring. Fun!

Anyway - will keep ya posted.. hope to get it all going here in the next couple weeks. Keep in touch!

Wish they had a photo attachment option ... would post a few shots.

Take care!
 

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72 Nova, Caltrac's and Splite Mono's, 10.5 tire, 600+ci, NA!
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Discussion Starter · #20 ·
WB's

Set the front end where you normally would. If the front end is too loose, it'll come up fast and hard and bang the wheelie bars just as hard.

That's the thing..

This is all new stuff... Entirely new setup, front and rear.

So, Im starting from scratch.


I'll get it figured out...

Sure love watchin' your car launch.... I'd be real happy with that. I just want another .6 or so off your time... ;).
 
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