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  #11  
Unread 07-23-2013, 06:02 PM
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Quote:
Originally Posted by Payton King View Post
the time to be the "bus driver" and taking us to school.

When you speak of a soft spring vs. stiffer spring, how big of a swing are you speaking/writing? I know of Corvette guys running C5's with 1200 lbs front and 900 lbs rear that are very fast. Seen guys more in the 700/800 range in the front fast as well. Assuming the above mentioned is 3000 pounds car weight.
Hi Payton,

Just a reminder, either conventional low travel/high roll ... or ... modern high travel/low roll set-ups will be fast if they're worked out, tested & tuned to optimum. The low travel/high roll set ups can be driven into the corner harder & the modern high travel/low roll set-ups can carry more corner speed, ending up being a little quicker/faster on overall lap times.

Even though the high travel/low roll set-ups have a slight advantage, if the set-up is less than optimum, a well tuned low travel/high roll set up can beat it on track. I say this from first hand experience running NASCAR Modifieds.

700# to 1200# front springs is a wide range of low travel/high roll set-up. They will have decent size sway bars, but nothing like the high travel/low roll set-ups. If you think about it, there are a gazillion spring, ARB, RC combinations. The 1200# front spring guys will have moderate size sway bars. The 700# front spring guys will have bigger bars. I think of these as Tweener set-ups. I see more Tweener set-ups in series where teams are slowly migrating to the newer high travel strategy.

You didn't say what series you were observing these cars in. Add that in when you respond. Are the C5's mildly modified or full race cars on kill ?

When we look at front spring rates on race cars, we have to be careful in what we lock in our minds as "fact" ... because the motion ratios (MR) vary so much. In coil over race cars, the MR can be twice that of a factory coil location. We typically locate coil overs as far out towards the wheel as possible to improve the shock control of that wheel.

For running short 1/4 to 3/8 mile oval tracks
... in a 2900# NASCAR Super Late Model stock car ... ... with coil overs in the front, the front spring rates range from 175-250#. In a similar type of car but with factory A-arms & stock spring location, that spring rate range will be 350-500#. *The wheel springs rates are the same because the MR is double in the coil over car, again, because the designer placed it out far.

But the front sway bar ... WOW ... could be anything from 800-1500# for short track racing. The rear springs will be pretty stiff too, because they don't run rear roll bars. 450-600# is pretty common. So with these huge sway bars & stiff rear springs, the cars run with very small roll angle & travel the front end 3" or more.

In road racing, where entry into many corners is a lot faster than above, similar 2900# modern road race cars will end up with a little more front spring rate ... say 500-600# with a stock type MR ... unless they run a progressive bump stop setup.
*P.S. In zero scrub radius road race cars, it is harder to achieve the high MR's because of the ball joint being placed so far into the wheel.

Don't under estimate the difference in rate if the car weighs 3000#, 3200#, 3500#, etc. The car weight matters significantly in working out the optimum rate for a high travel/low roll set-up.

The 3400# NASCAR Cup, Nationwide, Truck, K&N Pro Series & ARCA cars have a moderate MR & most typically run 340-350# front spring rate, but the ARB's range from 1600# to 4000# depending on the track size & speed.

So we're clear, I'm not trying to guide anyone to either set-up. I enjoy educating car guys about both. What's fun ... as long as you don't have a dog in the hunt ... is to watch cars with these two different set-ups race each other. If they're both good, the conventional car out brakes the high travel car on entry, and the high travel car carries more corner speed. It's fun to watch the back-n-forth.


.
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Last edited by Ron Sutton : 07-26-2013 at 10:04 AM.
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  #12  
Unread 07-23-2013, 06:15 PM
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Originally Posted by DaleTx View Post
If I had 10 clicks of adjustment with “1” being the least dampening and “10” the most, what would be a good starting point for setting up the dampening in the shocks?
Good stuff isn't Dale!

Something that was instilled in me by some guy named Malcolm Smith: When he gets a new bike with correct spring rates for him, part of his prep and break-in is to run the compression and rebound damping adjusters to max settings then count the range of clicks to full soft and leave it there for the first ride to let the suspension break in. This also lets him know firsthand what full-soft feels like. Next ride he'll ride awhile at full soft then adjust to full firm and ride it enough to get a feel for it, then he'll adjust to the middle settings. This allows him to understand through feel and experience what he has for range of adjustment in his suspension.

For those not familiar with Malcolm, he was a co-star with Steve McQueen in On Any Sunday and a very accomplished off-road racer. Also one of the kindest gentlemen you'll ever meet.


You might consider running three easy sessions as damping testing when you get your new shocks, then you'll know firsthand/seat of the pants what you've got to work with...........Ron - Is this a common practice in the car world or just for us two-wheelers?
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  #13  
Unread 07-23-2013, 06:16 PM
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Originally Posted by DaleTx View Post
I just read through all of your posts here this morning. This is great stuff… very well written and understandable for someone like myself that is fairly new to car building, and driving on road courses. Four years ago I joined a sports car club and went through a basic driver training course and learned about driving the proper lines, braking, tire contact patch, weight transfer, and some basic car set up like you have described. Now I am hooked on this sport and trying to improve in my driving and car set up.

I have a 69 Camaro that has been modified similar to a lot of cars on here, with modern engineered chassis and suspension components, bigger brakes, modern tires and wheels… etc. My car weighs ~3,400 lb with 53% of the weight on the front. I have 600 lb coils on the front with 240 lb/in leafs on the back.

Here is my question… If I wanted to set my car up for running on road courses primarily, and use the new school set up that you defined, what would be a good starting point for setting up the compression and rebound dampening for the front and rear shocks?

If I had 10 clicks of adjustment with “1” being the least dampening and “10” the most, what would be a good starting point for setting up the dampening in the shocks?

Front compression dampening: 1 thru 10?
Front rebound dampening: 1 thru 10?
Rear compression dampening: 1 thru 10?
Rear rebound dampening: 1 thru 10?

I am just trying to understand the basics of shock dampening, and how different dampening settings affect the handling of the car. At this point I know nothing about adjustable shocks since I have only run “Tuned Shocks”. I plan to invest in a set of adjustable shocks for my next upgrade, so I want to have some logic to use as a starting point for the adjustment.

Thanks again for taking the time to write up all this great information… much appreciated

Hi Dale,

I am a tad perplexed by your post.
Please help me get clarity, so I can give you the right info.

In the first half of the post, you describe your Camaro's set-up ... which is very conventional. But instead of asking about suggested spring & sway rates as a starting point ... your questions were on tuning the shocks.

Should we discuss spring & sway rates for a baseline high travel/low roll suspension set-up first? Or are you clear on that & just need shock tuning advice?


.
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Feel free to chime in or ask technical questions. I am here to help where I can.

Ron Sutton

Ron Sutton Race Technology
Your One Stop, Turn & Go Fast, Car Building Resource Center for Autocross, Track, Road Racing & Triple Duty Pro-Touring Cars

Check out our 400 Page Car Building Catalog HERE

Features: Suspension, Chassis, Cages, Brakes, Rear Ends, Engines, Transmisssions, Aero & Much, Much More!
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  #14  
Unread 07-23-2013, 06:17 PM
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Originally Posted by bret View Post
This needs to be included in a book. I think I can learn something here. Subscribed.
And thanks for taking the time to bring all this forward. It's always better to deal with an educated customer!
Hi Bret,

Feel free to chime in where needed.


.
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Feel free to chime in or ask technical questions. I am here to help where I can.

Ron Sutton

Ron Sutton Race Technology
Your One Stop, Turn & Go Fast, Car Building Resource Center for Autocross, Track, Road Racing & Triple Duty Pro-Touring Cars

Check out our 400 Page Car Building Catalog HERE

Features: Suspension, Chassis, Cages, Brakes, Rear Ends, Engines, Transmisssions, Aero & Much, Much More!
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  #15  
Unread 07-23-2013, 06:59 PM
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Quote:
Originally Posted by Sieg View Post
Good stuff isn't Dale!

Something that was instilled in me by some guy named Malcolm Smith: When he gets a new bike with correct spring rates for him, part of his prep and break-in is to run the compression and rebound damping adjusters to max settings then count the range of clicks to full soft and leave it there for the first ride to let the suspension break in. This also lets him know firsthand what full-soft feels like. Next ride he'll ride awhile at full soft then adjust to full firm and ride it enough to get a feel for it, then he'll adjust to the middle settings. This allows him to understand through feel and experience what he has for range of adjustment in his suspension.

For those not familiar with Malcolm, he was a co-star with Steve McQueen in On Any Sunday and a very accomplished off-road racer. Also one of the kindest gentlemen you'll ever meet.


You might consider running three easy sessions as damping testing when you get your new shocks, then you'll know firsthand/seat of the pants what you've got to work with...........Ron - Is this a common practice in the car world or just for us two-wheelers?

Or MSR, the clothing line known as Malcom Smith Racing, class act
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  #16  
Unread 07-23-2013, 07:01 PM
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Ron, thanks for taking the time to help edumicate us on these items. I know for one, i will be spending quite some time here over the next couple of weeks.

Handling is my favorite thing in a car or on a dirt bike, i know there two different animals, but some of the basic physics have some things in common.

Mike
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  #17  
Unread 07-23-2013, 07:06 PM
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Ron, Thank you for for starting this thread.

Can I get this thread in a leather back version that says Holy Bible by Ron Sutton on the front?

Matt
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  #18  
Unread 07-23-2013, 07:07 PM
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Wow lots to digest here. This is a great read thanks for sharing.
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  #19  
Unread 07-23-2013, 07:15 PM
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Quote:
Originally Posted by Ron Sutton View Post

Hi Dale,

I am a tad perplexed by your post.
Please help me get clarity, so I can give you the right info.

In the first half of the post, you describe your Camaro's set-up ... which is very conventional. But instead of asking about suggested spring & sway rates as a starting point ... your questions were on tuning the shocks.

Should we discuss spring & sway rates for a baseline high travel/low roll suspension set-up first? Or are you clear on that & just need shock tuning advice?


.
Hi Ron, Sorry for the confusion on my question... Please start out with discussion on spring and sway rates for a baseline high travel/low roll suspension set up (new school), and then secondly discuss tuning the shocks.

Thanks!
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  #20  
Unread 07-23-2013, 07:25 PM
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Quote:
Originally Posted by Sieg View Post
Good stuff isn't Dale!

Something that was instilled in me by some guy named Malcolm Smith: When he gets a new bike with correct spring rates for him, part of his prep and break-in is to run the compression and rebound damping adjusters to max settings then count the range of clicks to full soft and leave it there for the first ride to let the suspension break in. This also lets him know firsthand what full-soft feels like. Next ride he'll ride awhile at full soft then adjust to full firm and ride it enough to get a feel for it, then he'll adjust to the middle settings. This allows him to understand through feel and experience what he has for range of adjustment in his suspension.

For those not familiar with Malcolm, he was a co-star with Steve McQueen in On Any Sunday and a very accomplished off-road racer. Also one of the kindest gentlemen you'll ever meet.


Man ... Malcolm Smith. I haven't heard that name in awhile. Is he still alive? And is his business still going? I wore a MS chest protector when I was but a pup racing MX ... and that's been AWHILE.


You might consider running three easy sessions as damping testing when you get your new shocks, then you'll know firsthand/seat of the pants what you've got to work with...........Ron - Is this a common practice in the car world or just for us two-wheelers?
The driver getting the feel for the shocks & spring package is a huge deal. In my driver development program, we had a standing pre-season training program we called "spring training" & it had nothing to do with the season.

We would rent the track for a few days, and have the drivers drive the car ... and sneak up on the limits of grip under braking, cornering & exit ... with 42 different setups. We only made a spring, sway bar, roll center or shock valving change ... on one corner at a time. The crew had a step-by-step plan to make the car soft on each corner, medium, stiff ... with springs ... then too stiff ARB, too soft, etc. high & low roll centers, etc. We would run as many laps as needed ... until the driver felt the correct things ... and could tell the crew the difference from the previous set up. (The crew didn't let them see what the change was.)

This is one of the top training things we did with drivers to develop their feel & feedback. Later in the season, they could tell the crew, "I need more rebound on the front shocks" or "Let's lower the rear roll center" ... etc.

--------------------------------------------------------------------------------------------------------

As far as tuning the shock valving to learn what it does, what it feels like & what the handling result is, I have a pattern I like to follow ... but it depends if the shock is 1, 2, 3 or 4 way adjustable ... and if only 1 or 2 way ... are they rebound or compression adjustable.

After Dale gets me clear about springs ... we can move on talk shock strategy. It sounds like he hasn't bought them yet ... which means we should discuss basic valving & what type of adjustments you "really" want.


.
__________________
Feel free to chime in or ask technical questions. I am here to help where I can.

Ron Sutton

Ron Sutton Race Technology
Your One Stop, Turn & Go Fast, Car Building Resource Center for Autocross, Track, Road Racing & Triple Duty Pro-Touring Cars

Check out our 400 Page Car Building Catalog HERE

Features: Suspension, Chassis, Cages, Brakes, Rear Ends, Engines, Transmisssions, Aero & Much, Much More!
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