I set up my four wheel align ment for next week. I had a quea

ng8264723 · #1 (**permalink**) 07-30-2010, 08:50 PM

Any recomendations on settings? I know the owner of the shop and can tyell him what to dial in. By the way the car is running very well. Boy does it ever attrack attention. A few young girls stopped today to take pics
chris

Bob In Ct · #2 (**permalink**) 07-30-2010, 09:47 PM

Does the machine correct for the wider rear wheelbase?

RICK LAKE · #3 (**permalink**) 07-31-2010, 05:51 AM

ng8264723 Chris before you waste money on an alignment have the weights setup for the car corners with your butt in the seat. You want the car level and flat with a 49/51 front to back ratio. Also a 1/2 tank of gas in the car. If the car is off the handling will not be upto your expectations. Nothing is worse that a car that doesn't turn and handle for you. Rick L. If the alignment shop doesn't have scales, try and find a dirt track racer and offer him some money to setup your height and weights in the car.

ng8264723 · #4 (**permalink**) 07-31-2010, 06:24 AM

I'm not sure if it corrects for wider wheel bases. Rick, How do you set up the weights? Just add some iron to the rear corners?

patrickt · #5 (**permalink**) 07-31-2010, 06:46 AM

Quote:

Originally Posted by ng8264723

I'm not sure if it corrects for wider wheel bases. Rick, How do you set up the weights? Just add some iron to the rear corners?

No. Your garage must have an electronic four wheel scale. Then, you sit behind the wheel (or put sand bags representing you behind the wheel), loosen your sway bars, and then adjust your coil overs to achieve a 50% cross-weight (right front plus left rear). Then you tighten up the sway bars. This is absolutely, positively the first step before you get any alignment done. This can take a little time because every adjustment that you make to one wheel will have an effect elsewhere as well. But it will make a huge difference.

scottj · #6 (**permalink**) 07-31-2010, 08:13 AM

Corner weight changes don't affect alignment. Alignment changes can affect corner weights. I do the alignment first.

Z-linkCobra · #7 (**permalink**) 07-31-2010, 08:47 AM

Set the alignment first then the corner weights. like scott said...if you set the corner weights then set the alignment any change to castor or camber will affect your weight distribution.

Depending on what you plan to do with the car is where i would set my weights. If its just a daily driver...no track time. Set it up with about 52% front weight and 50% cross like patrick said if you can. Good stopping, good cornering.

Gotta remember when taking advice from patrick....he has to compensate for the extra weight of the double roll bar....lol

Sorry Patrick...couldnt resist

Gene

vector1 · #8 (**permalink**) 07-31-2010, 11:48 AM

adjust your ride height with driver wt., align with driver wt., then adjust corner wt. with driver wt. have fun with driver wt. i have my car aligned with 0 toe on the front, helps when caught in those asphalt ruts big trucks wear into the pavement, especially if you have wide tires. and you can leave the sway bars unhooked through all this and reattach when finished.

patrickt · #9 (**permalink**) 07-31-2010, 01:26 PM

Quote:

Originally Posted by scottj

Corner weight changes don't affect alignment. Alignment changes can affect corner weights. I do the alignment first.

I disagree. Corner weighting changes your ride heights at each corner of the vehicle, which will change your camber and toe. You should set your corner weights first. Now there's bound to be a technical article on the hot rodding sites that specifically address this question.

scottj · #10 (**permalink**) 07-31-2010, 01:57 PM

"Technical article on the Hot Rodding sites"

That's where you would look for tech advise?

If you're changing ride heights when adjusting corner weights then you're doing it wrong. Ride height is set 1st, then alignment, then scaling. Ride height is maintained through out and doesn't change when scaling.

I would suggest Longacre or Intercomp for tech advise on the correct procedure.

Here: Under "Tech Articles" from Longacre's site- Scaling made simple
http://www.longacreracing.com/articles/art.asp?ARTID=1

patrickt · #11 (**permalink**) 07-31-2010, 02:27 PM

Quote:

Originally Posted by scottj

"Technical article on the Hot Rodding sites"

That's where you would look for tech advise?

I'm thinking something more like Circle Track magazine or the like. I read your link though, but it didn't address which to do first. I did find a few threads where "non-authoritative" posts supported the corner-weight first procedure, but maybe they (and I) are wrong. Think you can find something out there that says you should do the alignment first and that was actually written by somebody that should know what they're saying?

scottj · #12 (**permalink**) 07-31-2010, 02:36 PM

Yes, paragraph two from the link I posted:

"Before you begin the scaling process you should make sure that the car is race ready. Fluid levels need to be topped off, stagger & tire pressure set, ride heights adjusted, Caster adjusted, Camber set, rear end square and the toe checked. You will also need to take advantage of the maximum left side weight and check to see if your total weight is within the rules and the front to rear balance is where you and your chassis builder want it. Emphasis should be placed on being race ready before you begin the final scaling procedure as all of these factors will have an effect on the end result."

Oh... by the way... I am an authority

patrickt · #13 (**permalink**) 07-31-2010, 02:41 PM

Quote:

Originally Posted by scottj

Yes, paragraph two from the link I posted:

"Before you begin the scaling process you should make sure that the car is race ready. Fluid levels need to be topped off, stagger & tire pressure set, ride heights adjusted, Caster adjusted, Camber set, rear end square and the toe checked. You will also need to take advantage of the maximum left side weight and check to see if your total weight is within the rules and the front to rear balance is where you and your chassis builder want it. Emphasis should be placed on being race ready before you begin the final scaling procedure as all of these factors will have an effect on the end result."

Oh... by the way... I am an authority

Yeah I saw that, but I read it to mean that you still had to do your alignment after the corner weights. Now as an example of the opposite treatment, these guys do the corner weights first and then do the aligment. http://www.moose-motorsport.co.uk/su...on_tuning.html Now to be honest, I've found sports car threads for vettes, Lotus, and others where posts say exactly the opposite (going in both directions), so it would be nice to have something even more specific.

scottj · #14 (**permalink**) 07-31-2010, 02:59 PM

Quote:

Originally Posted by patrickt

Yeah I saw that, but I read it to mean that you still had to do your alignment after the corner weights. Now as an example of the opposite treatment, these guys do the corner weights first and then do the aligment. http://www.moose-motorsport.co.uk/su...on_tuning.html Now to be honest, I've found sports car threads for vettes, Lotus, and others where posts say exactly the opposite (going in both directions), so it would be nice to have something even more specific.

Sorry, that's about as much effort I'm going to put into researching a procedure I've done about 1000 times. The only real proof anyway would be to buy your own scales and alignment equipment and see it for yourself... like I've done.

patrickt · #15 (**permalink**) 07-31-2010, 03:19 PM

From Dr. John Krane -- "Suspension 401":

Here is the order of operations:

1.initial set up
2.set ride height
3.corner-weight balance
4.adjust caster
5.adjust camber
6.adjust toe
7.adjust bump-steer
8.recheck caster, camber, toe, and readjust if necessary

So I guess this guy is just completely, dead wrong? You might want to at least read his reasoning, his resume, etc. http://home.comcast.net/~jkrane/susp401.html

Look Scott, I'm not just trying to beat you in an argument. I'd like to find out the suspension engineer's answer, but it's got to be more than just yours.

patrickt · #16 (**permalink**) 07-31-2010, 03:34 PM

If you have corner scales, now would be the time to look at weight distribution and adjust the chassis as required, because changing it later would change the final camber settings.

That's a quote from this guy, who essentially says the same thing as Dr. Krane, and has written a very detailed PDF on the subject. http://www.scuderiatopolino.com/Susp...20Set%20Up.pdf

Jerry Clayton · #17 (**permalink**) 07-31-2010, 03:35 PM

My answer would pretty much be the same as Scott's, but I might use more shorter words!!!
I probably also would start by saying"Listen carefully, as I'm only going to say this once"

I also have my own Hunter alignment rack

Jerry Clayton · #18 (**permalink**) 07-31-2010, 03:36 PM

Patrick

In an ongoing race operation, just view No 8 as being No 1----as it goes on and on and on

And this doesn't even get into checking tire temps and pressures as the car comes off the track

patrickt · #19 (**permalink**) 07-31-2010, 03:39 PM

... and changing corner weights has no affect on camber whatsoever?

scottj · #20 (**permalink**) 07-31-2010, 03:47 PM

Patrick, I'd don't consider you to be aurguing with me. I posted a link to the Longacre tech article and the article can stand on its own... I wouldn't believe me either. That said, If your make changes to caster and camber you will affect corner weights. That is right out of the Longacre tech article. So yes, the Dr. is dead wrong in his order. But, If you make changes to corner weight while maintaining ride heights, like you are supposed to, alignment will be unaffected.