Wheelbase

[wisdirtfan]

How many of you guys have actually checked the wheelbase on your cars? The reason I ask is we bought a new car this year and have all have all the mock up done on it and with the caster/camber and the links set just like the set up sheet says and the rear end is centered between the rails like it should be the right side is 103.5 and the left is 102. I called the car builder and he said that's the way it should be but when they check wheelbase in tech here they are checking both sides so I'm kinda confused about what to do? Any one have any suggestions?

[Confused?]

If it's legal, leave it alone. Some chassis builders turn the stub. That will cause that. And a large caster split will cause it.

[wisdirtfan]

Its not legal that's why I'm having an issue

[Confused?]

Then I would suggest that you call the builder again and inform him that this car is illegal, and ask what changes should be made. Just moving the rear end back can create several other problems if moved too far. How much short is it to be legal?

[wisdirtfan]

I did call him today. He said that's the way they are. Its supposed to be minimum 103 and my left side is 102. He also said just lengthen the links equally to make it legal

[grt74]

if it were me I would move both lower control arms forward,if you know how(it will take some fabricating on the up rights)but if your at the track the quick fix is to do what your builder said,just make sure the tech guys are doing it right!!from the center of the ball joint to the center of the rearend tube,we have had this problem before and had to prove it to the techs but it sounds like you got her figured out

[swartzman]

ding ding we have a winner.. grt74 is correct

[Confused?]

I would agree also. moving the fronts is a better plan.

[softshoe72]

Who is your chassis builder?

[zeroracing]

If he moves the fronts won't he run the risk of the motor being set to far back? If he is running a 6" rule right now and moves the LF forward one inch he will be 7, I have been etched on engine setback probably twice as often as wheelbase. Keep that in mind. Also some cars get pretty tight between rack and lower arm mounts. Going off memory I am not sure I have 1" of clear, without having to move the rack also.

Not saying what's right or wrong just reminding you it's all related, moving the rear back has a list of issues on its own too.

[grt74]

If he moves the fronts won't he run the risk of the motor being set to far back? If he is running a 6" rule right now and moves the LF forward one inch he will be 7, I have been etched on engine setback probably twice as often as wheelbase. Keep that in mind. Also some cars get pretty tight between rack and lower arm mounts. Going off memory I am not sure I have 1" of clear, without having to move the rack also.

Not saying what's right or wrong just reminding you it's all related, moving the rear back has a list of issues on its own too.

I can agree with that,measure 2 times,cut 1

[wisdirtfan]

I think that moving the rearend back is going to be the best solution because like you guys said moving the front will create even more headaches with the rack and setback. I'm not going to say who built it because I'm not the kind of person who will have something bad to say and then go back for help in the future if needed you don't bite the hand that feeds you.

[rcmaster]

try setting in the car and have someone measure

[Joe Porter]

I think we all know its a Rayburn

[Ltemodel]

I definitely would not move the front end. Unless you move the rack forward and everything, you will end up with ackerman problems.

Moving the rear rods back evenly is your best solution. You may need to reset your 5th coil vertical position also. Fixing the rear end won't screw with the drivability nearly as much as the front end.