Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

> Corner Balancing a Twisted Tub ..., Adventures in Weight-Distribution Land ...
SirAndy
post Apr 22 2006, 02:00 AM
Post #1


Resident German
*************************

Group: Admin
Posts: 41,891
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



so, McMark and i spent all day today trying to corner balance my tweaked and twisted tub.

i started out with all 4 corners the same ride-height. but the car felt awful. twitchy like hell and the left front always wanted to slide on me.

so, we got a bunch of scales and went to investigate.

almost 3/4 tank of gas and my fat ass in the drivers seat ...

the end result is still not perfect, but *much* better than before.
interestingly enough, now that the corners are balanced, the tub looks all crooked. (IMG:style_emoticons/default/wacko.gif)

i guess it makes sense, it's either:
- twisted tub, same ride height on all 4 corners, corner weights waaaay off
or
- twisted tub, corners balanced, tub looks bend.


we'll see how it holds up at the AX this AM, but it felt *much* better on the ride home from napa ...

thank you Mr. McMark!
(IMG:style_emoticons/default/smilie_pokal.gif)


here's a printout from the high-tech software we used to track the data ...


Attached thumbnail(s)
Attached Image
User is online!Profile CardPM
Go to the top of the page
+Quote Post
 
Reply to this topicStart new topic
Replies
McMark
post Apr 22 2006, 11:38 AM
Post #2


914 Freak!
***************

Group: Retired Admin
Posts: 20,179
Joined: 13-March 03
From: Grand Rapids, MI
Member No.: 419
Region Association: None



QUOTE(r_towle @ Apr 22 2006, 08:01 AM) *

Would you mind showing us how you used scales...without the special racing scales....


Attached Image

Ghetto corner balance. It actually worked pretty well. Scales went up to 360+ lbs even though they were only rated for 300 lbs. $6 per scale on sale. (IMG:style_emoticons/default/wink.gif)

QUOTE(rhodyguy @ Apr 22 2006, 08:31 AM) *

did you alter the corner balancing after the alignment? where did you make the biggest move? the adj perches, up front, or a combo?


The car was aligned when we started, now it's a little out of alignment. That the price you pay for night-before adjustments. The image Andy posted shows how obviously tweaked the chassis was. The left rear was above 600 lbs constantly, the front right was below 500 lbs most of the time and the front left/right rear were pretty stable and balanced at around 550 lbs. The left rear suspension pickup is probably tweaked downwards and the front right suspension is visibly tweaked upwards. So we made a lot of progress, considering the chassis.

Next step for Andy's car is the Celette Bench! (IMG:style_emoticons/default/wink.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Dave-O
post Apr 23 2006, 01:33 PM
Post #3


Is winter done yet?
***

Group: Members
Posts: 511
Joined: 26-August 03
From: Minneapols, MN
Member No.: 1,082







QUOTE
Ghetto corner balance. It actually worked pretty well. Scales went up to 360+ lbs even though they were only rated for 300 lbs. $6 per scale on sale. (IMG:style_emoticons/default/wink.gif)


That looks like a good idea for a corner blance on the cheap. How do you take into account for the motion of the suspension while the car is being lowered onto the scales? Does that bar slide easily on the scales?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Apr 23 2006, 01:54 PM
Post #4


Resident German
*************************

Group: Admin
Posts: 41,891
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



QUOTE(Dave-O @ Apr 23 2006, 12:33 PM) *

How do you take into account for the motion of the suspension while the car is being lowered onto the scales? Does that bar slide easily on the scales?


easy is not the word i would use but yes, we made sure everything was perfectly centered once the car sat on the scales.
we centered the bar on the scales, then centered the scales & bar under the tire, then moved the scales out/in along the bar until they both read the same.

(IMG:style_emoticons/default/smile.gif) Andy
User is online!Profile CardPM
Go to the top of the page
+Quote Post

Posts in this topic
SirAndy  

Reply to this topicStart new topic
3 User(s) are reading this topic (3 Guests and 0 Anonymous Users)
0 Members:

 

- Lo-Fi Version Time is now: 24th November 2024 - 11:21 AM