forward bite help

[57m]

hi we have a 2008 masterbuilt chassis we have for spring in it 550lf 450rf 250lr225rr we run a pop up shock in front of the rear end with about 200lb in it . my question is we have tried to tighten the car up and lowered the bars on the right side 3 and 3 down but still likes to drift off the corner. could it be that we have to much bar angle in the left upper bar that creates this problem. we also have the jbar angled. the other thing is it doesn't push coming in its perfect from entry to middle.

[latemodel86]

So you need side bite or foward bite?

[57m]

it would be forward bite a little more side bite would not be bad thanks

[latemodel86]

Give us a few more details, probably get a better response. Are you lighting up the tires while it's loose on exit? What does the car feel like, what are the track conditions when you have this problem, do you think you make any adjustments that could cause the car to do this?

[57m]

to respond to your question. track condition we are talking about is feature time the track starts to get black and shinny with a little bit of cushion. with the car it turns in free just fine it's from the middle out the tires run like they are running on oil just wanting to spin. just giving up to much time waiting to get back to full power. we tried moving the right side four links down to help this problem and it did nothing. we also were trying more wedge in the car to tighten it up that also did not work. just as a question with it being that dry slick would it work better to lower the left link and leave the right side up to take some of the steer out of the car this is the only other thing i could think that was causing this issue.

[latemodel86]

It seems like every post I make on 4m is about the 5th coil. lol Well, if you have an adjustable shock on the 5th, I'd start out by adding more rebound to the 5th for when the track goes to slick off for the feature. I've been fiddling with the 5th on my car lately, and I've learned a lot of your foward drive/bite comes from the 5th. When it lights up the tires and has no foward drive, like you're saying, I've learned it's the 5th shock you need to adjust, more than likely. I'd go possibly soften the spring on it too. For me, this has helped make the car squat on the RR more at all times and give it foward drive. You also may have to experiment how much fuel you run with the change you make to the spring. I'm not a setup god, but I've had this same problem before and these adjustments abover have helped me. Hope this helps and let us know how it goes!

[37mod]

take some bite out and lower the pressure in or remove the pop up shock. Your probably getting to much instant LR traction and losing late corner side bite. Is the RR a lot hotter than the LR? If it is you need to load the RR more.

[57m]

i was thinking about it and does anyone know how long the j bar is suppose to be in length for a 2008 masterbuilt we run 1/3 mile semi banked track.

[hall99]

take some bite out and lower the pressure in or remove the pop up shock. Your probably getting to much instant LR traction and losing late corner side bite. Is the RR a lot hotter than the LR? If it is you need to load the RR more.

I agree drop some LR out and look at a softer LR spring you shouldn't need over 80 - 100 lbs of LR bite.

[dualdj1]

so is it when you pick up the throttle that it's a problem? have you tried adding more fuel/decreasing stagger?

[57m]

we have tried to take out stager we start the feature with 32 gal of fuel. the issue is when on throttle

[grt74]

57m,everything im reading it sounds like the car is to tight getting in,you might think its great but ill bet your having to stab the gas to get her to turn and losing everything you gain getting in the corner,if the track is real slick youll have to drive the car alot straighter to get the drive your looking for,and this means a free entry jmo good luck

[57m]

Does anyone know what the length of the jbar right know its roughly 22 inches thanks

[dualdj1]

I don't think j-bar length is your issue.

drop lbl, and/or softer lr spring

[AntiSquat2006]

How does the car act getting into the corner?

[57m]

its kind of free coming in, rotating is good but from the middle off it just doesn't hook up

[grt74]

here are things that will give you added drive,add rear %,shorten rr bars,go up on rf spring,lengthen lr bars,stagger,and you asked about the jbar that will help middle more than anywhere else,my advise do one at a time to see what it does to the car,if you do more than one thing at a time you wont know what fixed it,there some ideas to remember every action has a reaction,so you may add drive and it be too much so youll have too free it up somewhere else,good luck

[57m]

thanks we'll give it a try.

[jesel45]

if your running 200 lbs of lr bite on a Mastersbilt, that is your problem. you car is way to tight. i tried that one night, we kept going a little further and a little further everynight until we finally overtightened the car, the car would be great to the apex of the turn, then it seemed like it would just jump out from under us and we had no drive whatsoever down the straights. try something like this

90 lbs LR with driver
54.0 rear %
54.5 -55 % left
48-49% cross
450 lf 400 rf
200 lr 250 rr
5th arm 350 @ 34" pre load it 3/4 to 1"
jbar 9" up on frame, 1" below pinion
6* cast RF 3* cast LF
set camber according to banking on your track
4" stagger
make sure fuel tank is always full at feature time

try this if you like but our car was lightning fast and we race on glass everynight

[RacinRupe52]

Jesel, was wondering what ride heights you are running? We have an 06 Mastersbuilt with the exact same problem and was thinking of trying your set-up. Thanks