I posted this in the 240SX General Section but I really want everyone's input.
Quote, originally posted by Lt.Mike »However, if you want the best bang for the buck, the same amount of money spent on front and rear STB's can be invested in Sway Bars instead. (Just my opinion)
Good opinion there bro. I've never thought of it that way before.Let's delve into this a bit, shall we?
STB vs Anti-swaybars. Which gives the bigger performance bang for the buck?
I may be wrong but my definitions are (please correct any errors I state) - STBs tighten up the chassis by reducing flex when turning, while Anti-swaybars prevent the chassis from tilting left or right while turning.
They both improve the handling characteristics of the car, but which would you buy if they both cost the same? (ie front and rear STB price = that of front and rear Anti-sway bars)
Is improved corning "feel/turn in" via STBs a better performance gain than a flat, go-kart like cornering that proper application of anti-sway bars can provide? Or vice versa?
This is very fascinating because one of these will be my next mod after my B&M shifter gets installed.
Opinions please.
You are invited to a discussion about Strut Tower Bars vs Antisway Bars.......
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MAXIMUS Nismo
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Re: You are invited to a discussion about Strut Tower Bars ... (MAXIMUS Nismo)
For the most part, you'll get better performance from a well-tuned swaybar than a strut bar. That's because the sway bar acts more directly with the suspension. What the sway bar does is hold together the LCA's on either side of the car so that the cornering forces are distributed more evenly on the inside and outside shocks/springs rather than having more force on the outside one. This, in turn, keeps the weight more distributed on your tires which keeps you planted on the ground.
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MAXIMUS Nismo
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Re: You are invited to a discussion about Strut Tower Bars ... (crzycav86)
good point there. But what are the LCAs?when you say the outside spring having more force on it, don't you mean the inside one? Cause if you turn right, doesnt the right spring get the brunt of the load? wait no I'm wrong. Cause if you turn right, the weight goes left therefore the outside spring is correct.
you da man dog!!
you da man dog!!
Re: You are invited to a discussion about Strut Tower Bars ... (MAXIMUS Nismo)
LCA = lower control arm.
Take a look at your stock sway bars. You'll see what they are.
Take a look at your stock sway bars. You'll see what they are.
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240marcuSX
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E46 M3
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Q45tech
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Re: (240marcuSX)
Just remember that oem load rated tires are marginal [on the front] and those coupled with a way too large [diameter] stock front sway bar is what causes all the understeer in the first place!
If anything when adding a stiffer rear bar you need to DECREASE the front bar diameter 5-7%..........not increase it as many aftermarkets do.
The tire slip angle vs load graph shows that adding extra load [via a larger sway bar] just takes away friction [increases slip angles].
Installing higher load index tires on the front [without heavier wheels] will reduce understeer as the tires have more reserve.
Shock towers bend [in or out] after years of stress minutely, creating camber changes...........1/8" can create a 1 degree camber change.
Old Shock tower can spread under extreme cornering load [<1/16".....0.0625" .......0.03 per side] creating 0.5 degree [-0.25 and + 0.25] camber changes.........but most tires, suspension bushings, upper mounts, etc are much worse.
If anything when adding a stiffer rear bar you need to DECREASE the front bar diameter 5-7%..........not increase it as many aftermarkets do.
The tire slip angle vs load graph shows that adding extra load [via a larger sway bar] just takes away friction [increases slip angles].
Installing higher load index tires on the front [without heavier wheels] will reduce understeer as the tires have more reserve.
Shock towers bend [in or out] after years of stress minutely, creating camber changes...........1/8" can create a 1 degree camber change.
Old Shock tower can spread under extreme cornering load [<1/16".....0.0625" .......0.03 per side] creating 0.5 degree [-0.25 and + 0.25] camber changes.........but most tires, suspension bushings, upper mounts, etc are much worse.
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ILikeMy240sx
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MAXIMUS Nismo
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If I recal correctly from all the stuff i've read and the Best Motoring/Drift Tenjuko vids I've seen, a larger/stiffer rear anti-sway bar increases Oversteer, while a larger/stiffer front bar increases Understeer. The trick is to set it up so that you have neutral handling while maintaining minimum to no body roll. I guess teh benefit of adjustable bars is that you can change the over/under steer characteristics based on road/driving style/competion etc. Some good stuff.
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Q45tech
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Re: (MAXIMUS Nismo)
"trick is to set it up so that you have neutral handling while maintaining minimum to no body roll" ..............?????
Contrary to what the name implies SWAY BARS should not be thought of as body roll reducers..........at least not much.
The rule of thumb for the street is that the bars should NEVER provide even HALF the roll resistance at either end........because they have no shocks to reduce oscillation in whip saw maneuvers [rapid left right left turns].
OEM might use a bar equal to the front spring stiffness if very isolated by rubber bushing on end links so the bar is effectively uncoupled in the first inch and progressively coupled as the body tries to roll 2>3". Progressive understeer as the tires load up creating even more understeer.
{{OEM front tire sizes are way too small way too weak for the static and handling [or braking load] applied at the extremes. The tires reach the absolute max rating [static plus braking load] yet the tires are not inflated to 44 psi............works because most don't brake at max for more than 3 seconds and the tires recover from the overload.}}
Sway bars REDUCE the traction on the tires by increasing the transferred load. Except when accelerating the rear tires [on a RWD] always have more traction availble than the front [which has greater weight]. Front tires overloaded, so by using, adding, or increasing the rear sway bar, you take away rear traction thus causing less understeer..........the roll couple resistance is more balanced and the tires [all 4] see more equal loads.
Think about it! The rear tires [54/46 weight balance] have 17% more [static or steady state] traction thus the front washes out more quickly.......the last thing you want is a stiffer front sway bar unless you increase the front tire load reserve by 17%...........which can be hard to do [a 98V vs. a 91V tire]. At least half that amount would be satisfactory considering everything but road racing occurs in a few seconds with recovery time in between.
But Acceleration Vectors reduce the available rear traction so power on vs. power off or steady speed is quite different.
Where do you desire neutrality in the beginning, middle, or coming out of a turn, at what speed, with what road friction coefficient, at what temperature?
See why oem set understeer as the goal.
Contrary to what the name implies SWAY BARS should not be thought of as body roll reducers..........at least not much.
The rule of thumb for the street is that the bars should NEVER provide even HALF the roll resistance at either end........because they have no shocks to reduce oscillation in whip saw maneuvers [rapid left right left turns].
OEM might use a bar equal to the front spring stiffness if very isolated by rubber bushing on end links so the bar is effectively uncoupled in the first inch and progressively coupled as the body tries to roll 2>3". Progressive understeer as the tires load up creating even more understeer.
{{OEM front tire sizes are way too small way too weak for the static and handling [or braking load] applied at the extremes. The tires reach the absolute max rating [static plus braking load] yet the tires are not inflated to 44 psi............works because most don't brake at max for more than 3 seconds and the tires recover from the overload.}}
Sway bars REDUCE the traction on the tires by increasing the transferred load. Except when accelerating the rear tires [on a RWD] always have more traction availble than the front [which has greater weight]. Front tires overloaded, so by using, adding, or increasing the rear sway bar, you take away rear traction thus causing less understeer..........the roll couple resistance is more balanced and the tires [all 4] see more equal loads.
Think about it! The rear tires [54/46 weight balance] have 17% more [static or steady state] traction thus the front washes out more quickly.......the last thing you want is a stiffer front sway bar unless you increase the front tire load reserve by 17%...........which can be hard to do [a 98V vs. a 91V tire]. At least half that amount would be satisfactory considering everything but road racing occurs in a few seconds with recovery time in between.
But Acceleration Vectors reduce the available rear traction so power on vs. power off or steady speed is quite different.
Where do you desire neutrality in the beginning, middle, or coming out of a turn, at what speed, with what road friction coefficient, at what temperature?
See why oem set understeer as the goal.
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Q45tech
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Re: (Q45tech)
Ever notice that many rear springs [measured at the wheel rate---tire road interface] are 20-25% softer [depending to total weight and wheelbase] than front yet the 54/46 weight ratio says they should be only 8% softer.
Higher performance cars will be closer to the ideal weight vs spring wheel rate RATIO.
The process of tuning the car to a specific speed to minimize the highway pitching when going over equal spaced road seams.......wheel base of asphalt laying machine which has its own periodic undulations.
The closer to the IDEAL [equal to body weight load ratio] spring weight ratio the faster the tuning speed, so stiffer springs create a higher tuning speed and funky things at 55-60 mph.
The problem is do you tune for a full passenger/fuel load or a single driver no passengers low fuel..............could be a 450 pound difference on the rear springs [225/123= 1.8-2" rear spring compression] and the 54/46 unloaded becomes 50/50 or 49/51 or 48/52 loaded.
Back to sway bars do you tune for a 54/46 or a 48/52 obviously fully loaded the rear will sway more with the 225# more load on EACH rear tire.
By the way that would require a 24 mm solid rear sway bar to offset [~~ 110 # per roll inch]........too close to equal to spring wheel rate for safety in marginal traction conditions..........a 20,21,22 mm [~~40-60-80# per inch] would be ideal and split the difference.
Higher performance cars will be closer to the ideal weight vs spring wheel rate RATIO.
The process of tuning the car to a specific speed to minimize the highway pitching when going over equal spaced road seams.......wheel base of asphalt laying machine which has its own periodic undulations.
The closer to the IDEAL [equal to body weight load ratio] spring weight ratio the faster the tuning speed, so stiffer springs create a higher tuning speed and funky things at 55-60 mph.
The problem is do you tune for a full passenger/fuel load or a single driver no passengers low fuel..............could be a 450 pound difference on the rear springs [225/123= 1.8-2" rear spring compression] and the 54/46 unloaded becomes 50/50 or 49/51 or 48/52 loaded.
Back to sway bars do you tune for a 54/46 or a 48/52 obviously fully loaded the rear will sway more with the 225# more load on EACH rear tire.
By the way that would require a 24 mm solid rear sway bar to offset [~~ 110 # per roll inch]........too close to equal to spring wheel rate for safety in marginal traction conditions..........a 20,21,22 mm [~~40-60-80# per inch] would be ideal and split the difference.
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hannibal
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Re: (SmithSR)
Q45tech, you are the man!
I had to read it a few times, but I just learned the actual goal in suspension tuning...
I had to read it a few times, but I just learned the actual goal in suspension tuning...
Re: (IWannaS15)
courtesy of team integra
strut barI see it all the time, people talking about all sorts of different bars claiming their Integra has superior handling to a McLaren F1. Well at least they have the power of possitive thinking on their side.
It's important to know exactly what types of bars are available and what their functions are. There are 6 different types of bars available for the Integra, 4 of them to stiffen the chassis and 2 to dictate cornering balance. This article covers the 4 strut/tie bars which work to stiffen the chassis. Information on the other 2 bars can be found in my Sway Bars article.
The main purpose of these bars is to brace the chassis at critical points. Normally during hard cornering the chassis will twist and flex due to the immense amount of force generated by 2600 lbs of metal wanting to move in a different direction than you are steering it. What this translates to is sluggish handling, and the chassis will end up playing catch up with itself.
All opposing forces to the chassis however come directly from the suspension components, so the solution is to brace both ends of the suspension together. If the bars do their job, the chassis will be held tightly together, and the forces that were once flexing the chassis are now going into turning the vehicle. This results in more responsive handling, and the vehicle will be able to make sudden changes in movement much quicker.
1. Front Upper Strut Tower BarConnects the front strut towers in the engine bay. The most popular bar that enthusiasts purchase mainly because of it's effect to the looks of the engine bay. Be wary though, just because it looks nice doesn't mean it will perform. For front-heavy cars such as ours the chassis will undergo the majority of flexing in the front and a quality bar on top is a must. The Integra GS-R and Type R come stock with this kind of bar.
2. Rear Upper Strut Tower BarConnects the rear strut towers in the trunk. Same effect as the front upper bar. The JDM Integra Type R comes with this bar stock.
3. Front Lower Tie BarConnects the lower front control arms. The least popular bar due to minimum availabilty and that it's the only strut/tie bar that you cannot show off. Not only that, but for lowered cars ground clearance can be an issue as it will have to hang down further than anything else under the car. There are only a few companies who offer this bar for Integras. Neuspeed makes a front lower tie bar for the non-vtec Integras while Spoon and Cusco make one for all applications, thanks to member b18c2 for the info on that.
4. Rear Lower Tie BarConnects the lower rear control arms. Also a popular bar due to it being visible from outside the car and will stiffen the rear without taking up space in the trunk. The problem I see with most Honda/Acura drivers is that they all have those shiny DC Sports bars which are too flimsy to actually do anything performance-wise. If you are not going for the rear upper strut bar due to trunk space issues at least get a good quality tie bar to make up for it. The Integra Type R comes stock with this kind of bar.
Quality bars to look for would be Mugen, Spoon, Neuspeed and Comptech. Bars to stay away from that will have no effect on performance would be DC Sports, APC, OBX, and any cheap no-name brand.
While all of these bars combined do a great job in stiffening the chassis and increasing cornering response, they still won't prevent body roll or "leaning" of the chassis. They also will not change the cornering balance of the vehicle. I've heard people say that a strut bar will "minimize understeer" however this is not true. The chassis may be held together tightly but it is still free to shift it's weight upon cornering. That's where the 2 other bars I mentioned earlier called sway bars come into play. More information on that can be found in the Sway Bars article.
sway barOtherwise called anti-roll bars, sway bars will make the most dramatic difference in your Integra's handling characteristics. The main purpose of sway bars are to reduce body roll. Sounds simple, but the effects of simply reducing the body roll of a vehicle are many.
A sway bar consists of the main portion which attaches directly to the chassis by bushings (allowing the bar to twist), and lever arms which connect to both sides of the suspension through end links.
When one side of the suspension compresses, the lever arm moves downward causing entire the sway bar to twist so the lever arm on the opposite side also attempts to move the same direction and compress it's own side as well. This resistance to movement increases the spring rate of your suspension when cornering. When both sides of the suspension are equal, the sway bar will have no effect. Here is a chopped down and simplified diagram of how the sway bar works.
Of course no sway bar is perfectly rigid, differences in suspension travel on opposite sides of the vehicle will still occur, so a sway bar can be thought of being a big spring. The bar is able to bend and flex as needed.
There are many benefits from a sway bar's effects of resisting opposite suspension travel.
The most stand out benefit that everyone talks about is the ability to change a vehicle's handling characteristics. Excluding the Type R, our front-wheel drive Integras come stock with pretty heavy understeer. This characteristic can be observed during accleration through a hard corner. The vehicle will have a tendancy to "plow" forward not turn as well as desired by the driver. Most will suggest that this can be solved with a larger sway bar in the rear. But why?
Roll stiffness determines the cornering load at any given end of the vehicle. In a corner, with a stiffer front and flimsy rear, centrifugal force will throw the majority of the weight of the vehicle to the rear. This will cause the chassis to lean upward in front, removing weight from the front wheels and effectively losing turning traction. With both a stiff front and stiff rear, the weight is balanced properly on both ends, and neutral handling is achieved.
Another side benefit is steering response. The further the body rolls, the longer it takes for the vehicle to become stable into a turn. With less body roll, steering response is greatly increased as the car will set in to a turn much quicker with less suspension travel. The quicker a vehicle finishes it's suspension travel, the quicker it can respond to new steering inputs by the driver.
Honda's suspension geometery is also subject to change depending on the height of the chassis in relation to the axle. When body roll occurs, changes in toe and camber also occur. This is okay to a degree, but when suspension travel has reached an extreme level, you can bet your suspension geometery is not where you want it to be for optimum handling performance.
Lastly, reducing the body roll will help the driver to maintain balance in the cockpit and concentrate on driving. The centrifugal forces of the corner are already pulling on the driver hard enough, when the car leans over the driver is then also subject to the force of gravity.
Sway bar sizing
The diameter of a sway bar determines it's stiffness. You can compare the stiffness of your stock sway bar to a bar you are thinking of purchasing by using a simple formula.
% stiffness compared to stock = (new diameter/stock diameter)^4
For example, if you have a GS-R with a 14mm rear sway bar and upgraded to a 22mm Type R rear sway bar you would calculate
(22/14)^4 = 6.10
This means a 22mm sway bar is roughly six times as stiff as the stock sway bar. Big difference don't you think? Subtract 1 at the end of that equation and you'll get a figure telling actually how much stiffer the bar is. So in that equation you'd come out with 5.10 or 510% stiffer than stock.
It's important to make sure the company you are buying your sway bar from includes proper mounting hardware. Stiff sway bars can easily tear out of the chassis during a hard corner if not mounted properly and your spring rates are too low to assist the bar in minimizing suspension travel. From what I know off hand, Comptech's sway bar is very good and comes with proper mounting hardware and will not tear out of the chassis. Comptech even guarantees it. Also BSQ makes a kit to allow a Type R rear sway bar to mount onto a non-Type R chassis so it will not tear out.
strut barI see it all the time, people talking about all sorts of different bars claiming their Integra has superior handling to a McLaren F1. Well at least they have the power of possitive thinking on their side.
It's important to know exactly what types of bars are available and what their functions are. There are 6 different types of bars available for the Integra, 4 of them to stiffen the chassis and 2 to dictate cornering balance. This article covers the 4 strut/tie bars which work to stiffen the chassis. Information on the other 2 bars can be found in my Sway Bars article.
The main purpose of these bars is to brace the chassis at critical points. Normally during hard cornering the chassis will twist and flex due to the immense amount of force generated by 2600 lbs of metal wanting to move in a different direction than you are steering it. What this translates to is sluggish handling, and the chassis will end up playing catch up with itself.
All opposing forces to the chassis however come directly from the suspension components, so the solution is to brace both ends of the suspension together. If the bars do their job, the chassis will be held tightly together, and the forces that were once flexing the chassis are now going into turning the vehicle. This results in more responsive handling, and the vehicle will be able to make sudden changes in movement much quicker.
1. Front Upper Strut Tower BarConnects the front strut towers in the engine bay. The most popular bar that enthusiasts purchase mainly because of it's effect to the looks of the engine bay. Be wary though, just because it looks nice doesn't mean it will perform. For front-heavy cars such as ours the chassis will undergo the majority of flexing in the front and a quality bar on top is a must. The Integra GS-R and Type R come stock with this kind of bar.
2. Rear Upper Strut Tower BarConnects the rear strut towers in the trunk. Same effect as the front upper bar. The JDM Integra Type R comes with this bar stock.
3. Front Lower Tie BarConnects the lower front control arms. The least popular bar due to minimum availabilty and that it's the only strut/tie bar that you cannot show off. Not only that, but for lowered cars ground clearance can be an issue as it will have to hang down further than anything else under the car. There are only a few companies who offer this bar for Integras. Neuspeed makes a front lower tie bar for the non-vtec Integras while Spoon and Cusco make one for all applications, thanks to member b18c2 for the info on that.
4. Rear Lower Tie BarConnects the lower rear control arms. Also a popular bar due to it being visible from outside the car and will stiffen the rear without taking up space in the trunk. The problem I see with most Honda/Acura drivers is that they all have those shiny DC Sports bars which are too flimsy to actually do anything performance-wise. If you are not going for the rear upper strut bar due to trunk space issues at least get a good quality tie bar to make up for it. The Integra Type R comes stock with this kind of bar.
Quality bars to look for would be Mugen, Spoon, Neuspeed and Comptech. Bars to stay away from that will have no effect on performance would be DC Sports, APC, OBX, and any cheap no-name brand.
While all of these bars combined do a great job in stiffening the chassis and increasing cornering response, they still won't prevent body roll or "leaning" of the chassis. They also will not change the cornering balance of the vehicle. I've heard people say that a strut bar will "minimize understeer" however this is not true. The chassis may be held together tightly but it is still free to shift it's weight upon cornering. That's where the 2 other bars I mentioned earlier called sway bars come into play. More information on that can be found in the Sway Bars article.
sway barOtherwise called anti-roll bars, sway bars will make the most dramatic difference in your Integra's handling characteristics. The main purpose of sway bars are to reduce body roll. Sounds simple, but the effects of simply reducing the body roll of a vehicle are many.
A sway bar consists of the main portion which attaches directly to the chassis by bushings (allowing the bar to twist), and lever arms which connect to both sides of the suspension through end links.
When one side of the suspension compresses, the lever arm moves downward causing entire the sway bar to twist so the lever arm on the opposite side also attempts to move the same direction and compress it's own side as well. This resistance to movement increases the spring rate of your suspension when cornering. When both sides of the suspension are equal, the sway bar will have no effect. Here is a chopped down and simplified diagram of how the sway bar works.
Of course no sway bar is perfectly rigid, differences in suspension travel on opposite sides of the vehicle will still occur, so a sway bar can be thought of being a big spring. The bar is able to bend and flex as needed.
There are many benefits from a sway bar's effects of resisting opposite suspension travel.
The most stand out benefit that everyone talks about is the ability to change a vehicle's handling characteristics. Excluding the Type R, our front-wheel drive Integras come stock with pretty heavy understeer. This characteristic can be observed during accleration through a hard corner. The vehicle will have a tendancy to "plow" forward not turn as well as desired by the driver. Most will suggest that this can be solved with a larger sway bar in the rear. But why?
Roll stiffness determines the cornering load at any given end of the vehicle. In a corner, with a stiffer front and flimsy rear, centrifugal force will throw the majority of the weight of the vehicle to the rear. This will cause the chassis to lean upward in front, removing weight from the front wheels and effectively losing turning traction. With both a stiff front and stiff rear, the weight is balanced properly on both ends, and neutral handling is achieved.
Another side benefit is steering response. The further the body rolls, the longer it takes for the vehicle to become stable into a turn. With less body roll, steering response is greatly increased as the car will set in to a turn much quicker with less suspension travel. The quicker a vehicle finishes it's suspension travel, the quicker it can respond to new steering inputs by the driver.
Honda's suspension geometery is also subject to change depending on the height of the chassis in relation to the axle. When body roll occurs, changes in toe and camber also occur. This is okay to a degree, but when suspension travel has reached an extreme level, you can bet your suspension geometery is not where you want it to be for optimum handling performance.
Lastly, reducing the body roll will help the driver to maintain balance in the cockpit and concentrate on driving. The centrifugal forces of the corner are already pulling on the driver hard enough, when the car leans over the driver is then also subject to the force of gravity.
Sway bar sizing
The diameter of a sway bar determines it's stiffness. You can compare the stiffness of your stock sway bar to a bar you are thinking of purchasing by using a simple formula.
% stiffness compared to stock = (new diameter/stock diameter)^4
For example, if you have a GS-R with a 14mm rear sway bar and upgraded to a 22mm Type R rear sway bar you would calculate
(22/14)^4 = 6.10
This means a 22mm sway bar is roughly six times as stiff as the stock sway bar. Big difference don't you think? Subtract 1 at the end of that equation and you'll get a figure telling actually how much stiffer the bar is. So in that equation you'd come out with 5.10 or 510% stiffer than stock.
It's important to make sure the company you are buying your sway bar from includes proper mounting hardware. Stiff sway bars can easily tear out of the chassis during a hard corner if not mounted properly and your spring rates are too low to assist the bar in minimizing suspension travel. From what I know off hand, Comptech's sway bar is very good and comes with proper mounting hardware and will not tear out of the chassis. Comptech even guarantees it. Also BSQ makes a kit to allow a Type R rear sway bar to mount onto a non-Type R chassis so it will not tear out.
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MAXIMUS Nismo
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (MAXIMUS Nismo)
The most common mistake people make is assumming that a spring's PUBLISHED stiffness is the actual as installed [angle and position relative to the wheel [not mounted directly to the wheel hub] is the actual on car stiffness.Then they forget to calculate the spring mounting compliance [rubber seat slop] then they forget to include the tire - wheel which is in series with the spring. Plus body flex. Most street cars real rear rates are 100-150 pounds per inch. With the sweet spot for comfort being 110-120. Including tires they are 85-130.
Almost all identical weight cars have pretty identical REAL SPRING Stiffness [tire wheel road interface stiffness] based on body weight and the class of vehicle [Lux, Sporty, extreme sporty] because all are tuned for 55-65 MPH.
Most cars have pretty much the same 5-6" road clearance and most shockshave a 7" max stroke.
A REAL 20% change in REAL spring stiffness is pretty extreme for the street if comfort is a consideration.
If a spring is mounted midways in the lower suspension arm the real stiffness is found by dividing by 4 if perfectly perpendicular. Same with sway bars. Even linear springs are not linear as mounted in suspension due to angle changes with motion.
Obviously the total spring rate changes as the tire pressure changes as the tire is ~~9-10-11 times stiffer than the spring [wheel rate].
Almost all identical weight cars have pretty identical REAL SPRING Stiffness [tire wheel road interface stiffness] based on body weight and the class of vehicle [Lux, Sporty, extreme sporty] because all are tuned for 55-65 MPH.
Most cars have pretty much the same 5-6" road clearance and most shockshave a 7" max stroke.
A REAL 20% change in REAL spring stiffness is pretty extreme for the street if comfort is a consideration.
If a spring is mounted midways in the lower suspension arm the real stiffness is found by dividing by 4 if perfectly perpendicular. Same with sway bars. Even linear springs are not linear as mounted in suspension due to angle changes with motion.
Obviously the total spring rate changes as the tire pressure changes as the tire is ~~9-10-11 times stiffer than the spring [wheel rate].
Re: (Q45tech)
This is kind of an old post but it keeps reinforcing the fact that I am totally ignorant on suspension tuning. Is there any quality books on the subject that I can start to learn some of the more technical talk?
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (kclo4)
http://www.me.utexas.edu/~lota...g.pdf
http://www.engr.colostate.edu/...g.pdf
http://www.minibaja.ufsc.br/ar...o.pdf
http://www.mscsoftware.com/sup...g.pdf
http://www.systemstech.com/Papers/P577RWA.pdf
http://www.delphi.com/pdf/tech...7.pdf
http://www.specprod.com/TECH_D...s.pdf
http://www.gsp9700.com/pub/technical/4869T.pdf
Results 31 - 40 of about 782 for -------- tire camber effects filetype:pdf.
The web is full if you use ADVANCED search with "pdf filter" then "ppt"
http://www.cb-racing.com/PilotCup_Presentation.PPT
Books to read: The Racing & High Performance Tire by Paul Haney Advanced Race Car Suspension by Steve Smith
http://www.engr.colostate.edu/...g.pdf
http://www.minibaja.ufsc.br/ar...o.pdf
http://www.mscsoftware.com/sup...g.pdf
http://www.systemstech.com/Papers/P577RWA.pdf
http://www.delphi.com/pdf/tech...7.pdf
http://www.specprod.com/TECH_D...s.pdf
http://www.gsp9700.com/pub/technical/4869T.pdf
Results 31 - 40 of about 782 for -------- tire camber effects filetype:pdf.
The web is full if you use ADVANCED search with "pdf filter" then "ppt"
http://www.cb-racing.com/PilotCup_Presentation.PPT
Books to read: The Racing & High Performance Tire by Paul Haney Advanced Race Car Suspension by Steve Smith
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (BomexS13)
He asked for " a recommended book" I thought 1000 pdf pages was enough to start.
Assuming your car is important to you-------10 hours per week [READING and working problems] for the rest of your life should be enough to keep current.............assuming you have the necessary mathematical background [differential calculus] and MAPLE/Mathematica/Matlab.
Tires/bushings are the most complicated as things change with temperature and age vs plain old metal..........shocks might be second.......yet few even know how they truely work....... dynamically.
Assuming your car is important to you-------10 hours per week [READING and working problems] for the rest of your life should be enough to keep current.............assuming you have the necessary mathematical background [differential calculus] and MAPLE/Mathematica/Matlab.
Tires/bushings are the most complicated as things change with temperature and age vs plain old metal..........shocks might be second.......yet few even know how they truely work....... dynamically.
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maxnix
- Posts: 22627
- Joined: Mon Jul 22, 2002 8:11 pm
- Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45
Re: (AZhitman)
If you really want to learn, you must follow and read the links. Thanks, Dennis!
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MAXIMUS Nismo
- Posts: 1535
- Joined: Tue Aug 20, 2002 7:23 am
- Car: 95 240sx SE
- Contact:
Re: (gogg)
Yeah, and ebay STB's don't do a damn thing but look cool.gogg wrote:ebay stb's are like $20 each
sways are like 150 each...
I would say that using strut tower bars is fairly pointless unless you ar running higher spring rates like coilovers. When you run high enough spring rates, you end up flexing the chassis quite a bit more than with stock rates, because the body is absorbing a lot of force. The difference in handling that comes with strut tower bars is more noticeable when you have coilovers.
Re: (naed240sx)
Agreed. strut bars and sway bars have almost nothing to do with each other in terms of function. The only thing they really share is a similar name, which is what I think confuses a lot of people(like the thread-starter).naed240sx wrote:Yeah, and ebay STB's don't do a damn thing but look cool.
I would say that using strut tower bars is fairly pointless unless you ar running higher spring rates like coilovers. When you run high enough spring rates, you end up flexing the chassis quite a bit more than with stock rates, because the body is absorbing a lot of force. The difference in handling that comes with strut tower bars is more noticeable when you have coilovers.