Suspsension Analysis
10-20-2013, 10:31 PM
#16
Track Day
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10-20-2013, 11:50 PM
#17
Matt,
When I wanted a racier suspension and departed from stock shocks to double motons I did the calcs for ride freq etc to arrive a empirical spring rates for a ferrari I was working on. I took real weights of all the components sprung and unsprung and cornerweights too which by is self is a pita because the most accuracy is done with disassembly. The back bone of my referrence was Staniforth's "competition car suspension." Then I gave the same data to performance shock inc. in sonoma and they did the custom valving. It all seemed to work I'm very happy with the result. The only improvements I could do now would be with a laptimer lots of new tires and a bunch of springs and many shock setting combo's. In other words it ain't happening. And people think golf is a hard game...
When I wanted a racier suspension and departed from stock shocks to double motons I did the calcs for ride freq etc to arrive a empirical spring rates for a ferrari I was working on. I took real weights of all the components sprung and unsprung and cornerweights too which by is self is a pita because the most accuracy is done with disassembly. The back bone of my referrence was Staniforth's "competition car suspension." Then I gave the same data to performance shock inc. in sonoma and they did the custom valving. It all seemed to work I'm very happy with the result. The only improvements I could do now would be with a laptimer lots of new tires and a bunch of springs and many shock setting combo's. In other words it ain't happening. And people think golf is a hard game...
10-21-2013, 04:23 PM
#18
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Well, the way many top professional driver coaches and car engineers objectively validate setup improvement on the same day, the same track and the same driver is percentage full throttle over the lap... ☺️
Also, the objective way to set shocks is included in both John's advanced AiM course and in Bob Knox's book. There is a particular distribution of the histogram bins that result in better car behavior, universal among platforms.
It pains me that folks who are hard pressed to drive three laps within a tenth and a half together at places like Elkhart, the Glen and VIR are qualitatively validating shock changes in one or two click increments... But that's just the former chief mechanic in me talking, not the driver coach! ��
Do you have Ross' e-paper on shock adjustment?
Also, the objective way to set shocks is included in both John's advanced AiM course and in Bob Knox's book. There is a particular distribution of the histogram bins that result in better car behavior, universal among platforms.
It pains me that folks who are hard pressed to drive three laps within a tenth and a half together at places like Elkhart, the Glen and VIR are qualitatively validating shock changes in one or two click increments... But that's just the former chief mechanic in me talking, not the driver coach! ��
Do you have Ross' e-paper on shock adjustment?
I have Ross' book on adjustments among some other resources as well. I'm now pretty sure that this is a fox hole I should have never looked down!
I agree on people's "feeling" of changes. I have some pretty amusing stories about that....
10-21-2013, 06:17 PM
#19
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As someone who has spent the last 10 years watching engineers come and go and try and tune street stock cars, be careful what you wish for. I run some spring rates on our cars that people think are nuts UNTIL they drive them and then they're like "ohhhhhhhh."
We are probably best served if you just email me directly, tell me when was the last time you liked your setup, what did you do to it and what doesn't do now?
Here's a perfect example. You can have a $15,000 Motec system, $5000 in shock potentiometers and either not know how to read it or be gathering data incorrectly because your diff is too locked or your tires are just not sticky enough.
At the end of the day, it depends on the tire and the driver. Some drivers like stiff cars and some don't. Shocks need to be valved correctly and then they either work or they don't. You should seriously look at someone professional building your shocks. All of us teams do it. It takes a lot of the guess work out.
Shocks are funny. 80% of the racing world (DRIVERS AND ENGINEERS) thinks they do 1 thing when they don't. You need your shocks to be right for a "range of spring rates." then you adjust the ***** if you make big spring or bar changes OR if you go from Sebring 1 day to Miller Motorsports Park the next. We did an entire season of Rolex racing on the Cayman and I did 1 spring change, a few bar adjustments here and there and some **** turning DURING AN ENTIRE SEASON. If it works for us, it should work for you.
We are probably best served if you just email me directly, tell me when was the last time you liked your setup, what did you do to it and what doesn't do now?
Here's a perfect example. You can have a $15,000 Motec system, $5000 in shock potentiometers and either not know how to read it or be gathering data incorrectly because your diff is too locked or your tires are just not sticky enough.
At the end of the day, it depends on the tire and the driver. Some drivers like stiff cars and some don't. Shocks need to be valved correctly and then they either work or they don't. You should seriously look at someone professional building your shocks. All of us teams do it. It takes a lot of the guess work out.
Shocks are funny. 80% of the racing world (DRIVERS AND ENGINEERS) thinks they do 1 thing when they don't. You need your shocks to be right for a "range of spring rates." then you adjust the ***** if you make big spring or bar changes OR if you go from Sebring 1 day to Miller Motorsports Park the next. We did an entire season of Rolex racing on the Cayman and I did 1 spring change, a few bar adjustments here and there and some **** turning DURING AN ENTIRE SEASON. If it works for us, it should work for you.
10-21-2013, 08:57 PM
#20
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As someone who has spent the last 10 years watching engineers come and go and try and tune street stock cars, be careful what you wish for. I run some spring rates on our cars that people think are nuts UNTIL they drive them and then they're like "ohhhhhhhh."
We are probably best served if you just email me directly, tell me when was the last time you liked your setup, what did you do to it and what doesn't do now?
Here's a perfect example. You can have a $15,000 Motec system, $5000 in shock potentiometers and either not know how to read it or be gathering data incorrectly because your diff is too locked or your tires are just not sticky enough.
At the end of the day, it depends on the tire and the driver. Some drivers like stiff cars and some don't. Shocks need to be valved correctly and then they either work or they don't. You should seriously look at someone professional building your shocks. All of us teams do it. It takes a lot of the guess work out.
Shocks are funny. 80% of the racing world (DRIVERS AND ENGINEERS) thinks they do 1 thing when they don't. You need your shocks to be right for a "range of spring rates." then you adjust the ***** if you make big spring or bar changes OR if you go from Sebring 1 day to Miller Motorsports Park the next. We did an entire season of Rolex racing on the Cayman and I did 1 spring change, a few bar adjustments here and there and some **** turning DURING AN ENTIRE SEASON. If it works for us, it should work for you.
We are probably best served if you just email me directly, tell me when was the last time you liked your setup, what did you do to it and what doesn't do now?
Here's a perfect example. You can have a $15,000 Motec system, $5000 in shock potentiometers and either not know how to read it or be gathering data incorrectly because your diff is too locked or your tires are just not sticky enough.
At the end of the day, it depends on the tire and the driver. Some drivers like stiff cars and some don't. Shocks need to be valved correctly and then they either work or they don't. You should seriously look at someone professional building your shocks. All of us teams do it. It takes a lot of the guess work out.
Shocks are funny. 80% of the racing world (DRIVERS AND ENGINEERS) thinks they do 1 thing when they don't. You need your shocks to be right for a "range of spring rates." then you adjust the ***** if you make big spring or bar changes OR if you go from Sebring 1 day to Miller Motorsports Park the next. We did an entire season of Rolex racing on the Cayman and I did 1 spring change, a few bar adjustments here and there and some **** turning DURING AN ENTIRE SEASON. If it works for us, it should work for you.
10-22-2013, 05:38 PM
#21
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Matt,
Unfortunately I suck up data like a vacuum. I am more than happy to look at anything, especially if you have data. BUT, I am every bit as interested in your interpretation of "what is slowing you down the most" per the current setup.
Even if you someone understood data inside, out and sideways, at the end of the day, one person's preference is all that matters.
Unfortunately I suck up data like a vacuum. I am more than happy to look at anything, especially if you have data. BUT, I am every bit as interested in your interpretation of "what is slowing you down the most" per the current setup.
Even if you someone understood data inside, out and sideways, at the end of the day, one person's preference is all that matters.
10-22-2013, 11:34 PM
#22
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John - data sent to the info@ address. Let me know if you need it sent somewhere else.
