Corner Weight Balancing of 914s, The benefits of equalizing the side-to-side corner wts. |
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Corner Weight Balancing of 914s, The benefits of equalizing the side-to-side corner wts. |
stewteral |
Dec 9 2009, 12:43 AM
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#1
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Hey 914ers:
If you have been following my posts on 914 chassis settings, here is one that applies to ALL 914's. To start, per my posts: -I Squared the chassis with paralleled strings to measure and set the toe, front and rear. (Front = 0 to -1/16 toe, rear = 0 to -1/8" toe) =Results: steering a bit "nervous", but all else stable. -Camber: For Street cars, Standard front with -1 to -1.5 degrees rear. =Results: nothing noticeable. -I bumpsteered the front suspensions to within 0.008" from prefect at 2" compression. =Results: nothing I could feel driving the car on the street. TBD on-track. -CORNER WEIGHT BALANCED THE CHASSIS: With the car weighted for the driver weight, I adjusted the rear spring ht. and the front torsion bar ride height. For the rear, large diameter washers can be added to make adjustments, while the front is too easy with an 11 mm wrench. =Results: WONDERFUL!! With all the previous chassis settings done, the car still wanted to pull to the right as though I were on a highly crowned road. After the balancing the corner weights, side-to-side, the car now runs STRAIGHT and TRUE right down the road. The sense through the steering is now light, equal and very linear as to where I want to aim the car. Conclusion: Take the time to either build wt check lever, as per my photo or find a very strong STEEL ladder and wing it. Regardless, the benefit from the effort is completely WORTH IT!!! If you have any questions, please let me know! Terry stewteral@verizon.net |
J P Stein |
Dec 9 2009, 07:01 AM
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#2
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
Basically, you did it backward. Changing the ride height alters the alignment.
My corner balance has no discernible effect on performance....tho it hasn't been far off to begin with.....40-50 lbs tops. |
Joe Ricard |
Dec 9 2009, 07:06 AM
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#3
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Word on what the old guy said.
ride hieght to get in the ball park rough alignment to get the wheels all rolling in generally the same direction then corner balance then align to a specification |
ME733 |
Dec 9 2009, 10:22 AM
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#4
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Senior Member Group: Members Posts: 842 Joined: 25-June 08 From: Atlanta Ga. Member No.: 9,209 Region Association: South East States |
Hey 914ers: If you have been following my posts on 914 chassis settings, here is one that applies to ALL 914's. To start, per my posts: -I Squared the chassis with paralleled strings to measure and set the toe, front and rear. (Front = 0 to -1/16 toe, rear = 0 to -1/8" toe) =Results: steering a bit "nervous", but all else stable. -Camber: For Street cars, Standard front with -1 to -1.5 degrees rear. =Results: nothing noticeable. -I bumpsteered the front suspensions to within 0.008" from prefect at 2" compression. =Results: nothing I could feel driving the car on the street. TBD on-track. -CORNER WEIGHT BALANCED THE CHASSIS: With the car weighted for the driver weight, I adjusted the rear spring ht. and the front torsion bar ride height. For the rear, large diameter washers can be added to make adjustments, while the front is too easy with an 11 mm wrench. =Results: WONDERFUL!! With all the previous chassis settings done, the car still wanted to pull to the right as though I were on a highly crowned road. After the balancing the corner weights, side-to-side, the car now runs STRAIGHT and TRUE right down the road. The sense through the steering is now light, equal and very linear as to where I want to aim the car. Conclusion: Take the time to either build wt check lever, as per my photo or find a very strong STEEL ladder and wing it. Regardless, the benefit from the effort is completely WORTH IT!!! If you have any questions, please let me know! Terry stewteral@verizon.net STEWTERAL....Please explain the "Large diamenter washer" rear balance adjustments...( .I assume you do not have adjustable spring perches) and I suppose you have to remove the rear spring to insert the "large washers"..correct?...what size washer, inside/ outside dia.?...what thickness washer resulted in ...X.?.....weight transfer?...please explain because I would like to avoid the cost of coil-overs.,,,thanks. |
SirAndy |
Dec 9 2009, 11:52 AM
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#5
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Resident German Group: Admin Posts: 41,854 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Word on what the old guy said. ride hieght to get in the ball park rough alignment to get the wheels all rolling in generally the same direction then corner balance then align to a specification (IMG:style_emoticons/default/agree.gif) |
stewteral |
Dec 12 2009, 12:26 PM
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#6
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Basically, you did it backward. Changing the ride height alters the alignment. My corner balance has no discernible effect on performance....tho it hasn't been far off to begin with.....40-50 lbs tops. ricky Racer: You're overstating the situation: my adjustments were 30 - 40 Degrees of turn on the torsion bar height adjuster that allowed the front-end to balance within 10 lbs side to side WITH DRIVER WEIGHT on-board. Original corner weigths were off by 100 lbs: Keep in mind this is a V8 car. The affects to chassis settings are extremely small and WILL improve on-track performance by making the car's handling more consistent side-to-side and more comfortable to drive. A comfortable car is a fast car over the long run. Terry |
stewteral |
Dec 12 2009, 12:49 PM
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#7
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Hey 914ers: If you have been following my posts on 914 chassis settings, here is one that applies to ALL 914's. To start, per my posts: -I Squared the chassis with paralleled strings to measure and set the toe, front and rear. (Front = 0 to -1/16 toe, rear = 0 to -1/8" toe) =Results: steering a bit "nervous", but all else stable. -Camber: For Street cars, Standard front with -1 to -1.5 degrees rear. =Results: nothing noticeable. -I bumpsteered the front suspensions to within 0.008" from prefect at 2" compression. =Results: nothing I could feel driving the car on the street. TBD on-track. -CORNER WEIGHT BALANCED THE CHASSIS: With the car weighted for the driver weight, I adjusted the rear spring ht. and the front torsion bar ride height. For the rear, large diameter washers can be added to make adjustments, while the front is too easy with an 11 mm wrench. =Results: WONDERFUL!! With all the previous chassis settings done, the car still wanted to pull to the right as though I were on a highly crowned road. After the balancing the corner weights, side-to-side, the car now runs STRAIGHT and TRUE right down the road. The sense through the steering is now light, equal and very linear as to where I want to aim the car. Conclusion: Take the time to either build wt check lever, as per my photo or find a very strong STEEL ladder and wing it. Regardless, the benefit from the effort is completely WORTH IT!!! If you have any questions, please let me know! Terry stewteral@verizon.net STEWTERAL....Please explain the "Large diamenter washer" rear balance adjustments...( .I assume you do not have adjustable spring perches) and I suppose you have to remove the rear spring to insert the "large washers"..correct?...what size washer, inside/ outside dia.?...what thickness washer resulted in ...X.?.....weight transfer?...please explain because I would like to avoid the cost of coil-overs.,,,thanks. Hey ME733: Sorry if I confused you: -I DO have adjustable rear spring perches, so the "Washer Idea" does not apply to me. If you have adjustable perches, you're SET. -The "Washer Idea" was Blue Skying a way for those with STOCK non-adustable perches to be able to shim-up a spring and balance corner weight. The washers would need to have an ID to fit around the shock body and have an OD large enough to sit under the spring. I doubt washers this size can be easily found, possibly at McMaster-Carr. So I would look to making them myself out of aluminum sheet with 1 sheet-steel washer against the spring to take the wear. I'll leave it to an interested forum member to give it a try. Best, Terry |
J P Stein |
Dec 12 2009, 01:51 PM
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#8
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
Of course, sonny, you can't learn squat from a fat old guy.
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stewteral |
Dec 15 2009, 10:57 PM
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#9
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Of course, sonny, you can't learn squat from a fat old guy. Hey Ricky Racer, Are you saying you have a lot of racing and race-car prep experience? I'd be interested in learning what experience you have with which cars and tracks. Have you always done your own chassis prep and tuning? What kind of equipment do you use for chassis alignment? Have you raced a number of different types of cars? Do you have any special tricks you have picked up over the years? Thanks, Terry |
koozy |
Dec 16 2009, 02:31 AM
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#10
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Senior Member Group: Members Posts: 651 Joined: 21-July 07 Member No.: 7,931 Region Association: None |
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SirAndy |
Dec 16 2009, 12:17 PM
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#11
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Resident German Group: Admin Posts: 41,854 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Hey Ricky Racer, Are you saying you have a lot of racing and race-car prep experience? I'd be interested in learning what experience you have with which cars and tracks. Have you always done your own chassis prep and tuning? What kind of equipment do you use for chassis alignment? Have you raced a number of different types of cars? Do you have any special tricks you have picked up over the years? I'm not Ricky Racer nor do i play him on TV ... (IMG:style_emoticons/default/biggrin.gif) I happen to be the crew chief for a small Porsche racing team. We consistently place in the top 3 with many, many race wins and overall class wins under our belt. To answer your questions: - All the chassis prep and tuning is done by us. - We use electronic scales and the Smart Racing strings, camber plates and camber gauges for alignment. - I race and work mostly on Porsche's. 911, GT2, 914, Boxster, you get the idea. - Yes. My point? I agree with the old fart. You're doing it in reverse. We always start by setting the ride height close to where we want it, then corner balance the car to fine tune, then align the car. In that order. (IMG:style_emoticons/default/popcorn[1].gif) Andy |
J P Stein |
Dec 16 2009, 01:45 PM
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#12
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
Heh....you will be in 20-30 years. (IMG:style_emoticons/default/shades.gif) Yes, Terry, I do all the work on my car....or did till I sold it, soup to nuts. The exceptions were 2. I don't mount tires and I don't do the alignment by myself, but....A buddy up the street has an alignment shop. We stick it on his alignment rack and have at it. No strings here...not accurate enuff. IIRC, the thrust angle last time was .003 deg.....that's close enuff. |
SirAndy |
Dec 16 2009, 01:58 PM
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#13
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Resident German Group: Admin Posts: 41,854 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
No strings here...not accurate enuff. IIRC, the thrust angle last time was .003 deg.....that's close enuff. Naaaa ... First off, we don't do degrees. (IMG:style_emoticons/default/ohmy.gif) Yepp, you heard that right! We measure in 1/2mm increments over the diameter of the wheel. (IMG:style_emoticons/default/screwy.gif) I'll bet you a good cuban cigar that i can set up the 911 with the scales and strings just as good as your buddy with all his high-tech equipment. Plus, using the scales and strings, i can make predictable changes at the track between run sessions if needed. In fact, i don't think i've had a race weekend where we didn't play with the alignment settings. (IMG:style_emoticons/default/idea.gif) Andy |
Joe Ricard |
Dec 16 2009, 04:05 PM
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#14
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
And are you winning?
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SirAndy |
Dec 16 2009, 05:22 PM
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#15
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Resident German Group: Admin Posts: 41,854 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
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J P Stein |
Dec 16 2009, 05:33 PM
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#16
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
Terry:
10-12 years back the car was Green....now it isn't. Which part of the build are you interested in? I have a boatload of "tricks" that most oldtimers here already know of. Attached image(s) |
ChrisFoley |
Dec 16 2009, 08:48 PM
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#17
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I am Tangerine Racing Group: Members Posts: 7,962 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
I have a boatload of "tricks" that most oldtimers here already know of. Like having a youngster drive the car for you, lol. (IMG:style_emoticons/default/lol-2.gif) |
J P Stein |
Dec 17 2009, 06:24 AM
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#18
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
A man's got to know his limitations.
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stewteral |
Dec 17 2009, 09:50 PM
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#19
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
A man's got to know his limitations. JP Stein: So your "racing experience" is 10 years with a slalom car? Did you do any of the driving, or just the wrenching? Did the car ever get to a race track? Why is the front-end so stiff on the slalom car that the inside front wheel is lifted of the ground? Is that to compensate for an open Diff in order to put the power down? Best, Terry |
stewteral |
Dec 17 2009, 10:05 PM
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#20
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Hey Ricky Racer, Are you saying you have a lot of racing and race-car prep experience? I'd be interested in learning what experience you have with which cars and tracks. Have you always done your own chassis prep and tuning? What kind of equipment do you use for chassis alignment? Have you raced a number of different types of cars? Do you have any special tricks you have picked up over the years? I'm not Ricky Racer nor do i play him on TV ... :D I happen to be the crew chief for a small Porsche racing team. We consistently place in the top 3 with many, many race wins and overall class wins under our belt. To answer your questions: - All the chassis prep and tuning is done by us. - We use electronic scales and the Smart Racing strings, camber plates and camber gauges for alignment. - I race and work mostly on Porsche's. 911, GT2, 914, Boxster, you get the idea. - Yes. My point? I agree with the old fart. You're doing it in reverse. We always start by setting the ride height close to where we want it, then corner balance the car to fine tune, then align the car. In that order. :popcorn: Andy Hey Andy: I have no argument with where to start the chassis adjustment process, but after finishing the first round of settings, one should go back around and verify/adjust the others.....wouldn't you agree? Since every adjustment effects the others, it is a continuing process of refining all the settings. Now after setting toe, camber, ride height and corner weight, I will go back and verify toe and camber settings. Have fun with your track cars, you have 2 truly great tracks up in NOCAL, while I have only WSIR and Buttonwillow here in SOCAL Best, Terry |
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