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Author Topic:   forward bite
21racer
Dirt Full Roller

Total posts: 56
posted October 04, 2004 06:10 PM  
this week i seem to have forward bite problems last week good forward bite track was black with rubber last week this week only dry slick. car is 4 bar lr z-link rr the car didnt seem to get up on the bars to plant left rear tire one other car that was a 4bar car was getting up quickly and blew the field away. my question is will more left upper bar angle make it get up on bars better or do i need something else

dirtywrench13
Dirt Freak

Total posts: 324
posted October 05, 2004 12:03 PM  
I'D ADD SOME BALAST IF YOU THINK YOU HAVE ENOUGH SPRING TO CARRY IT.DOESN'T SOUND AS THOUGH YOU HAVE A BAR ANGLE PROBLEM.

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 05, 2004 12:14 PM  
how much angle do you have now? top and bottom

What about rear% etc.

21racer
Dirt Full Roller

Total posts: 56
posted October 05, 2004 07:59 PM  
left bars are at 5 down on lower 15 up on upper. dont have any scales so dont have numbers to post if adding balast where would be best location

Ego Racing
Dirt Forum Champ
Total posts: 724
posted October 05, 2004 08:32 PM  
On a dry slick mount the weight up high and on the right side. You want the chassis to roll over on the right side to plnt the right rear tire.

dirtywrench13
Dirt Freak

Total posts: 324
posted October 06, 2004 06:10 AM  
I'VE ALWAYS BEEN TOLD LOW LEFT, BUT WE ALWAYS HAVE TROUBLE GETTING IT TO ROLL OR NOT ROLL AS MUCH. WE SEEM TO USE LEFT SIDE WEIGHT TO OUR ADVANTAGE THOUGH.

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 06, 2004 07:55 AM  
double posted..

[This message has been edited by dirtbuster (edited October 06, 2004).]

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 06, 2004 07:57 AM  
Low left will not help promote sidebite. IT will basically just be along for the ride. It may help coming off to a point but if you cnat get through the corner faster you are gong to get beat coming off. I never mount lead lower than the middle of the fuel cell. And most of the time it is at the upper frame rails to help roll the car over and stick. But if you dont have a problem sticking the car gettin gin then dotn worry about.

For forward bite you need more bar angle. raise your upper bar 1 hole at least. When our track is super dry we run 20 in the top and 8 in the bottom, but the bottom is more of a driver feel thing. definetely put ore in the top bar.

dirtywrench13
Dirt Freak

Total posts: 324
posted October 06, 2004 03:52 PM  
WE USE THE J-BAR FOR SIDE BITE,AND THE WEIGHT ON LOW LEFT TO ROLL OVER MORE, IS WHAT WE WERE TOLD AND IT SEEMED TO WORK.

GRTWallbanger
Dirt Maniac

Total posts: 196
posted October 07, 2004 08:21 AM  
Would mounting lead low and on the left help the car roll over??
I have mine up high and on the right and in front of the cell.The car does not roll or pick the LF at all?

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 07, 2004 08:37 AM  
Like I said above i would at least try to keep it at the mid height of the fuel cell which is near the center of gravity height. Remember ther is a difference between body roll and weight transfer. Body roll is dependant on springs. Put a really soft srpign in the RR and it may roll over and drag the fender but a stiffer spring will hold the car up and plant the tire making it stick harder instead of compressing. WEight transfer depends on center of gravity height and roll center height. Moving the panhard bar moves the roll center, moving weight moves the center of gravity. A lower panhard bar and high lead will transfer more weight than a high panhard and low lead. If you have your lead high and need the car to transfer more on dry slick try lowering your panhard bar.

The left front doesnt lift because the car rolls over. It lifts because of angle in either panhard bar or trailing arms or both.

dirtywrench13
Dirt Freak

Total posts: 324
posted October 07, 2004 03:14 PM  
YOU PROBABLY GO UP 1 RATE IN SPRING ON BOTH REARS,AND LEAVE THE REAR BARS ALONE. THIS SHOULD HELP FOREWARD BITE. OR YOU COULD LIGHTEN UP ON THE SHOCKS, JUST DEPENDS ON WHAT YOU WANT TO ACCOMPLISH,FASTER ACTION,OR SMOOTHER CONTROLL.

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 07, 2004 03:26 PM  
WE moved to a short panhard bar because it helped with forward bite off the corner more than the jbar. It will also help get up on the bars better. It gets a bad rap because it does react quick and you can go overboard with it and you will hate it. I think a lot of people try to run to much angle and that is the problem.

Do you have any idea what rear% youhave. We run up to 59% or more with our 4 bar car when its slick. You could try mounting 50# of lead as far back in the car as possible (beside or behind fuel cell if possible) but fairly even side to side and see if that helps, then you would know if it was a weight issue.

In my opinion if it wont get on the bars then you need more bar angle either in the top or bottom or both. Id start with the top bar at least 18-20degrees and prob try raising the bottom bar a hole. REmember when the driver get in you lose angle so depending on how you measured it your 15 could end up only about 12-13 . We run ours with driver in the car at 20 upper 8 lower.

GRTWallbanger
Dirt Maniac

Total posts: 196
posted October 08, 2004 07:52 AM  
Will more bar angle in the Left Lower bar also help forward bite and help the car get up on the bars??

dogwalker
Dirt Full Roller

Total posts: 65
posted October 08, 2004 08:30 AM  
GRT, yeah and it also increases dynamic rear steer.


WPP
Dirt Freak

Total posts: 451
posted October 10, 2004 07:08 AM  
Dirtbuster how long is your shortbar panhard bar and how much rake do you run thanks

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 11, 2004 08:11 AM  
wpp,
I cant remember for sure on length its about 10 1/2 -11" i think. With about 3" rake from end to end.

WPP
Dirt Freak

Total posts: 451
posted October 13, 2004 03:35 PM  
dirtbuster i put a 12in short bar on today with about 3 1/2 in of rake i still can lower the bar on the chassis side some the rear is about a 1/4 too the left. I was running a 17 in bar do you mind telling me what i can expect from the shorter bar as getting in the corner and off the corner. will it loosen in and tighten off or will it tighten it all the way around this is a 112 wheelbase dw8 4-bar lr z-link spring clamped infront on lr and on top of rear on rr with about 20pds lr with about a 1/2 static rear steer and i still have not tried the fifth coil deal thanks

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 13, 2004 04:43 PM  
If you can take a little more angle out I would. Just seemed like if we went past 3" it got touchy but our bar is a little shorter than yours which will make a difference. Another thing we found is we seemed to be able to run it a little higher overall than the other bars.
Cant really tell you personally what it will do as I dont drive but based on the drivers words it tends to tighten up the car from the middle out, and improves forward bite. He never really mentioned anything on getting in. It reacts quicker than a jbar or even the 17" bar, which is good on dryslick but I think it can be a handful on tacky if the car is tight anyway.

WPP
Dirt Freak

Total posts: 451
posted October 14, 2004 11:08 AM  
I did raise it up to the 3rd hole on the pinion and most of the time i start in the 2nd hole i measured today from the ground and the pinion mount was 8 1/4 and the frame side was 11 1/4 and you If the car is tight can i raise the shortbar up some more or should i go back to the long straight bar thanks

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted October 14, 2004 11:13 AM  
If it is tight at late entry and middle then i would try raising it and see what happens, or try moving some lead around.

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