Corner weight explained

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Corner weight explained

Postby Scandinavian Flick » Tue Apr 29, 2008 11:04 am

I had an idea of how important it was, but didn't really understand it. In my search for knowledge, I found this article that explains it really well and thought I would share:

http://www.hotrod.com/howto/113_0309_co ... index.html
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Re: Corner weight explained

Postby Ski_Lover » Wed Apr 30, 2008 1:30 pm

Definitely a good thing to do. If you have adjustable coilovers, I highly recommend getting it done. (if you don't mind the looks of your car being a little uneven in ride height front to back)
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Re: Corner weight explained

Postby loanpro » Wed May 14, 2008 7:51 pm

The Miata is well balanced to begin with, so fine tuning your suspension that may or may not give you uneven stance will probably not be as noticeable.
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Re: Corner weight explained

Postby Scandinavian Flick » Thu May 22, 2008 2:47 pm

Blue posted these articles in his corner balancing day thread. They explain it really well, so I am copying it here:

rhdek9 wrote:For those who want some kind of explanation as to what corner balancing is, here are some articles about it:
1. http://www.nsxprime.com/FAQ/Performance ... alance.htm" onclick="window.open(this.href);return false;
2. http://www.elephantracing.com/techtopic ... alance.htm" onclick="window.open(this.href);return false;
3. http://www.dietersmotorsports.com/tech/ ... alance.htm" onclick="window.open(this.href);return false;

The way I explain it is this: think of a chair (car). Think of the 4 legs on the chair (the 4 wheels/tires). Now imagine if 1 leg is shorter. The “chair” wobbles right? Same concept.
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Re: Corner weight explained

Postby mackniler » Thu Aug 28, 2008 1:28 am

Ski_Lover wrote:Definitely a good thing to do. If you have adjustable coilovers, I highly recommend getting it done. (if you don't mind the looks of your car being a little uneven in ride height front to back)

what does it look like front higher or back higher, (when its balanced)
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Re: Corner weight explained

Postby nitewing117 » Thu Aug 28, 2008 1:57 am

mackniler wrote:what does it look like front higher or back higher, (when its balanced)


it really depends. on my car, the stance is a bit off cuz I had the corner balancing done when I was in the car, but I really dont care cuz i know it handles a lot better. IIRC, the left side of my car is a bit higher than the other, and the corners are a bit different too.
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Re: Corner weight explained

Postby Scandinavian Flick » Thu Aug 28, 2008 8:36 am

Does it mostly depend on f/r weight distribution of the car? FCs are almost a perfect 50/50, so when mine got balanced it doesn't have any noticable difference and looks totally flat even. Side to side might be slightly different though for the reason Glenn stated.

Might have to do this again soon because I want to raise the car about an inch.
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Re: Corner weight explained

Postby mackniler » Thu Aug 28, 2008 9:13 pm

u got more pics of the fc??
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Re: Corner weight explained

Postby Scandinavian Flick » Thu Aug 28, 2008 10:41 pm

Here are the only decent pics I have of it recently:
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Its not much, but it gets me from point A to point B... most of the time... and its kinda fun...
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Re: Corner weight explained

Postby nitewing117 » Fri Aug 29, 2008 1:59 am

TehOutsyder wrote:Does it mostly depend on f/r weight distribution of the car? FCs are almost a perfect 50/50, so when mine got balanced it doesn't have any noticable difference and looks totally flat even. Side to side might be slightly different though for the reason Glenn stated.

Might have to do this again soon because I want to raise the car about an inch.



Its not so much 50-50 f/r, but equal cross weights. My car is nearly 50-50 f/r (off by about a 1%) and off by 2.3% L/R, but blue pointed out that unless you're trying to shift all the weight around the car and make each corner even, the easiest one to do (with noticeable improvements) is the cross weights (diagonals).

note that I notice it having different heights when I'm out of the car; when I'm in it, i have no idea. Same thing applies to my alignment.
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Re: Corner weight explained

Postby Ski_Lover » Tue Nov 18, 2008 9:43 am

Logan,

Your chair with uneven leg lengths is a very good analogy to uneven corner weights.

I get my car corner balanced to 50:50 cross weights. The article you linked at the beginning of the post talks about uneven cross weights as "wedge". Race cars are sometimes set up with slight wedge (or the reverse) for a particular race track. Indeed, this is what set-up sheets are all about (including bars, ride height, springs, tire pressures, ...) for each track.

Tony at TC Design (who does my alignments and corner weights) tells me most drivers will not notice a difference until the cross weights are off by more than 2%. Beyond that, you will notice the car handles better in a Right vs. Left turns (or visa versa), or you might notice your threshold breaking has been reduced (especially if you don't have ABS).
Craig Northcutt

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Re: Corner weight explained

Postby Popstoy » Sat Jun 27, 2009 9:29 pm

Corner weight is measured diagnal, right-front to left rear, and left front to right rear, not side to side, or front to back. If done correctly both fronts will be the same, and both rears will be the same, but on a Miata the front to back will normally be 1 1/2 to 2 percent heavier in front. Corner weight can be adjusted with spring preload, but is best done with adjustable shock body lenghts. In order for the ride height to be the same, on both sides, sprung weight needs to be shifted. Typically on a corner weighted Miata, the ride height is within 1/4", side to side, generally in back. Corner weighting should always be done in conjunction with a alignment, and as a precission alignment makes a significant difference to handling, so does corner weighting. Bob
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Re: Corner weight explained

Postby rennkafer » Sat Jun 27, 2009 9:35 pm

Corner weight can be adjusted with spring preload, but is best done with adjustable shock body lenghts.


I'd love to see a valid engineering reason for that... keeping in mind that the term "spring preload" is a misnomer unless your dampers are at full extension at static ride height.
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Re: Corner weight explained

Postby Popstoy » Sat Jun 27, 2009 10:41 pm

Bill, I understand your point, and agree you. But spring preload, if it isn't equal, side to side, can change the static position in the shock travel. Most high quality performance shocks, even some of the not so high quality, are gas charged, even having progressive bump dampning. Tein even warns, in their set up instructions, too carefully adjust the preload equally for each end of the car, and recommends using shock body lenght for ride height and corner weighting on their flex's. While I'm not familar with the internal design of the Tein's, I know Fox and Olin's are internally designed to use the gas charged and increasing bump dampning the further they go into bump travel. I suspect Tein does the same. Bob
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Re: Corner weight explained

Postby Ski_Lover » Mon Jun 29, 2009 2:35 pm

Popstoy wrote:Corner weight is measured diagnal, right-front to left rear, and left front to right rear, not side to side, or front to back.


Correct. you want the sum of the diagonal weights to be equal.

Popstoy wrote: If done correctly both fronts will be the same, and both rears will be the same


Incorrect. Above means that you'd have equal weights at all four corners. In reality, Driver side of the car will be heavier, so fronts and backs will not be equal.

Popstoy wrote: Corner weighting should always be done in conjunction with a alignment, and as a precission alignment makes a significant difference to handling, so does corner weighting. Bob


Definitely. Changing ride height at a particular corner (in order to balance corner weights), will affect suspension geometry which affects alignment.
Craig Northcutt

D-Prepared '90 Miata (TC Design Cage & Prep, Rebello built '00 1.8L NA, Ankeny Racing Custom Penske shocks, OSG superlock Diff, 949 15x10 6UL's, Hoosier Tires, 1924 lbs w/50# Rear Ballast)

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Re: Corner weight explained

Postby Popstoy » Mon Jun 29, 2009 8:55 pm

Craig, maybe I didn't make myself clear, or maybe you just misunderstood what I was saying. I didn't say the front and back would be equal weight after corner weighting, and in fact they won't, the fronts will be heavier, by a percent or two. What my intenion was to indicate the two front will be the same, and the two backs will be the same. Corner weighting should be done just like a precission alignment, with your big ass in the seat, mine was. Bob
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Re: Corner weight explained

Postby Potsticker » Thu Nov 29, 2012 11:05 pm

those are some good materials thanks

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