Suspension: When to adjust what?
#22
which means you could have 150lbs. lf / 50lbs rr = 200lbs.
then 125lbs rf / 75lbs lr = 200lbs. and hypothetically have similar steering left or right. in this example the lf has more weight than any corner, but it shouldn't steer differently. what could, especially at that track cw, is higher temps from all the right hand turns. it could raise the tire psi, more on one side and that could affect the handling. on jakes car we ran 2psi less cold on the left and after the session they were all equal.
#24
If you haven't already you should subscribe to racecar engineering, if for nothing else but the ****.
http://www.racecar-engineering.com/
This is supposed to be a very good book. A bit heavy on the maths, keeping your college texts nearby would be helpful.
http://www.millikenresearch.com/rcvd.html
http://www.racecar-engineering.com/
This is supposed to be a very good book. A bit heavy on the maths, keeping your college texts nearby would be helpful.
http://www.millikenresearch.com/rcvd.html
#26
Seriously guys…at first some enthusiasts buy a cool car…many do some bling mods…a few do motor mods…some learn to drive…some modify the suspension…combinations. There are many ways to enjoy automobiles. If you get into track / autocross, it really pays to learn the fundamentals of suspensions and handling, keep records, try to improve your setup, datalog, make parts, video, read, discuss.
Miatadotnet is pretty much for everybody…CR more for the bling/slam crowd…this place (to me) seems mostly about the motor, engine, boost etc (which makes sense given the forum name and the interest of many posters). It's nice to see a few here showing interest in learning more about suspension and handling rather than the latest boost mod. After all…it's not hard to hold the gas pedal down
Now…Mark is mostly used to dealing with experienced and pro drivers. I point this out because some enthusiasts leap to making all sorts of changes to their car to get rid of problems the car may or may not really have. You can really get lost if you go down that path. It's pretty common.
See…the driver can experience a car and then when trying to produce a good result may need to develop a driving strategy which may or may not be as expected. Since they will do things like take different lines, enter corners certain ways, give it up in other places than others. That's part of how the SM guys can produce quite decent lap time results on about any track.
#27
Mark's a Racecar Engineer / Consultant. I think those Honda guys are just storing some of his material on their site.
Seriously guys…at first some enthusiasts buy a cool car…many do some bling mods…a few do motor mods…some learn to drive…some modify the suspension…combinations. There are many ways to enjoy automobiles. If you get into track / autocross, it really pays to learn the fundamentals of suspensions and handling, keep records, try to improve your setup, datalog, make parts, video, read, discuss.
Miatadotnet is pretty much for everybody…CR more for the bling/slam crowd…this place (to me) seems mostly about the motor, engine, boost etc (which makes sense given the forum name and the interest of many posters). It's nice to see a few here showing interest in learning more about suspension and handling rather than the latest boost mod. After all…it's not hard to hold the gas pedal down
Now…Mark is mostly used to dealing with experienced and pro drivers. I point this out because some enthusiasts leap to making all sorts of changes to their car to get rid of problems the car may or may not really have. You can really get lost if you go down that path. It's pretty common.
See…the driver can experience a car and then when trying to produce a good result may need to develop a driving strategy which may or may not be as expected. Since they will do things like take different lines, enter corners certain ways, give it up in other places than others. That's part of how the SM guys can produce quite decent lap time results on about any track.
Seriously guys…at first some enthusiasts buy a cool car…many do some bling mods…a few do motor mods…some learn to drive…some modify the suspension…combinations. There are many ways to enjoy automobiles. If you get into track / autocross, it really pays to learn the fundamentals of suspensions and handling, keep records, try to improve your setup, datalog, make parts, video, read, discuss.
Miatadotnet is pretty much for everybody…CR more for the bling/slam crowd…this place (to me) seems mostly about the motor, engine, boost etc (which makes sense given the forum name and the interest of many posters). It's nice to see a few here showing interest in learning more about suspension and handling rather than the latest boost mod. After all…it's not hard to hold the gas pedal down
Now…Mark is mostly used to dealing with experienced and pro drivers. I point this out because some enthusiasts leap to making all sorts of changes to their car to get rid of problems the car may or may not really have. You can really get lost if you go down that path. It's pretty common.
See…the driver can experience a car and then when trying to produce a good result may need to develop a driving strategy which may or may not be as expected. Since they will do things like take different lines, enter corners certain ways, give it up in other places than others. That's part of how the SM guys can produce quite decent lap time results on about any track.
So the point of this post is to yet again claim you know a lot and we dumb powerheads not only don't know much, but can't drive, and we should be glad you're part of this forum? Way to stick on topic.
#28
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Again, rather than contribute to the thread, he "listens to the sound of his own voice". He also fails to notice that roughly 100% of the fastest Miatas in the nation are on this board, and we didn't get here without fundamentals.
#30
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Mark's a Racecar Engineer / Consultant. I think those Honda guys are just storing some of his material on their site.
Seriously guys…at first some enthusiasts buy a cool car…many do some bling mods…a few do motor mods…some learn to drive…some modify the suspension…combinations. There are many ways to enjoy automobiles. If you get into track / autocross, it really pays to learn the fundamentals of suspensions and handling, keep records, try to improve your setup, datalog, make parts, video, read, discuss.
Miatadotnet is pretty much for everybody…CR more for the bling/slam crowd…this place (to me) seems mostly about the motor, engine, boost etc (which makes sense given the forum name and the interest of many posters). It's nice to see a few here showing interest in learning more about suspension and handling rather than the latest boost mod. After all…it's not hard to hold the gas pedal down
Now…Mark is mostly used to dealing with experienced and pro drivers. I point this out because some enthusiasts leap to making all sorts of changes to their car to get rid of problems the car may or may not really have. You can really get lost if you go down that path. It's pretty common.
See…the driver can experience a car and then when trying to produce a good result may need to develop a driving strategy which may or may not be as expected. Since they will do things like take different lines, enter corners certain ways, give it up in other places than others. That's part of how the SM guys can produce quite decent lap time results on about any track.
Seriously guys…at first some enthusiasts buy a cool car…many do some bling mods…a few do motor mods…some learn to drive…some modify the suspension…combinations. There are many ways to enjoy automobiles. If you get into track / autocross, it really pays to learn the fundamentals of suspensions and handling, keep records, try to improve your setup, datalog, make parts, video, read, discuss.
Miatadotnet is pretty much for everybody…CR more for the bling/slam crowd…this place (to me) seems mostly about the motor, engine, boost etc (which makes sense given the forum name and the interest of many posters). It's nice to see a few here showing interest in learning more about suspension and handling rather than the latest boost mod. After all…it's not hard to hold the gas pedal down
Now…Mark is mostly used to dealing with experienced and pro drivers. I point this out because some enthusiasts leap to making all sorts of changes to their car to get rid of problems the car may or may not really have. You can really get lost if you go down that path. It's pretty common.
See…the driver can experience a car and then when trying to produce a good result may need to develop a driving strategy which may or may not be as expected. Since they will do things like take different lines, enter corners certain ways, give it up in other places than others. That's part of how the SM guys can produce quite decent lap time results on about any track.
#31
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#32
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You have to be careful with generalizing all right turns too. I spent some time trying to figure out why the black car wouldn't turn in for T10 at Laguna, until I realized that it was perfect everywhere else and T10 just naturally causes understeer from the terrain.
#34
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What did you do to add some speed in this turn? Hotter entry and harder trail brake?
#35
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Yep. Move the braking point up ~75ft and ride the brakes the whole way through turn-in until it's basically over-rotated. There's so much camber in T10 that if you don't over-rotate on entry, you'll be fully hooked before the apex and pushing on exit. I got through there fast one time at my last Laguna day, and the steering wheel was straight the entire time.
#36
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So today, I read this and it blew my mind
http://www.eviltwinmotorsports.com/w...ter-2006.6.pdf :
I'm suddenly unsure which way to turn the rebound ****.
http://www.eviltwinmotorsports.com/w...ter-2006.6.pdf :
As to the effect of shocks, yes stiffening the fronts will add understeer during entry and stiffening the rears will add oversteer, provided that the road surface is smooth. This effect requires that the car have a roll velocity outward, and that this be the main source of suspension movement. When the car is cornering steady-state on a smooth surface, the roll velocity should be zero, the suspension should have displacement from static but not velocity, and shocks shouldn't matter. During exit, the car has a roll velocity inward (it's de-rolling). In this situation, the effect of the shocks reverses. Stiffening the fronts adds oversteer; stiffening the rears adds understeer.
So to add understeer or oversteer overall, we use the relative stiffness of the front and rear springs (and/or bars, if present). To change entry and exit properties in opposite directions, we use the relative stiffness of the front and rear shocks (remember, only on smooth surfaces).
So to add understeer or oversteer overall, we use the relative stiffness of the front and rear springs (and/or bars, if present). To change entry and exit properties in opposite directions, we use the relative stiffness of the front and rear shocks (remember, only on smooth surfaces).
#37
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Yep. Move the braking point up ~75ft and ride the brakes the whole way through turn-in until it's basically over-rotated. There's so much camber in T10 that if you don't over-rotate on entry, you'll be fully hooked before the apex and pushing on exit. I got through there fast one time at my last Laguna day, and the steering wheel was straight the entire time.
#38
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A damper's job in high shaft speed is to keep the tire on the surface, and in a perfect world over bumps with no change in load. What is the damper's job in low speed, glass smooth weight transfer?
I know low-speed compression is there to control roll to the magical number that works on every track, but what does rebound specifically do?
I'll ask questions later about the gray area between high and low speed, and the magical shim-stack transitions from high to low. This is getting scary, I may want 3-way adjustables soon.
I know low-speed compression is there to control roll to the magical number that works on every track, but what does rebound specifically do?
I'll ask questions later about the gray area between high and low speed, and the magical shim-stack transitions from high to low. This is getting scary, I may want 3-way adjustables soon.
#39
Yep. Move the braking point up ~75ft and ride the brakes the whole way through turn-in until it's basically over-rotated. There's so much camber in T10 that if you don't over-rotate on entry, you'll be fully hooked before the apex and pushing on exit. I got through there fast one time at my last Laguna day, and the steering wheel was straight the entire time.
#40
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Yup, I'd do the same. By getting more rotation earlier on such a turn, mid and and corner exit understeer and steering lock is reduced, and powerdown can be earlier. This is a key autocross driving skill too BTW. Combine with well timed throttle kicks for alien driving at those speeds. It helps alot to have good brake bias here.