BTCC Honda Civic Typr R nary lifts a rear wheel - why?
12-15-2003, 12:51 PM
#27
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Re: (MightyMouseTech)
Originally Posted by MightyMouseTech
I had the opportunity to tech a couple of BTCC cars.(2000 Williams) These things are not nearly as nose heavy as our street based bretheren. When you open the front hood, it is very apparent to what lengths they go to to move the weight bias to the rear. When you opened the hood, all you could see of the engine was the top of the valve cover and the intake stacks, the engine was at a ~60deg angle and shoved under the passenger floor. I would imagine that these cars run a hell of a lot closer to a 50/50 weight distribution than most of us can only dream of. That will go a LONG way to keeping the car flat in the corner.
However this would not explain why the RSX's in the WCTC hardly lift, since they are not moving the engine back, and I would suspect they still have 60% or so of the weight on the front tires.
Total weight transfer is independent of suspension type or stiffness. It only depends on c.g. height, track, total weight and corner speed. The portion of lateral load transfer allocated to the front or rear tires depends only on roll stiffness (given equal mass) distribution, and so this is also independent of suspension type, except for roll centre height. Part of the load transfer is for the unsprung mass, which is suspension independent. Part of the load transfer goes directly through the suspension links or bushings, and part of it goes through the roll centre, with the moment arm between the roll centre and the center of gravity for the particular axle. It only depends on the spring rates and sway bar rates as seen at the contact patch. The roll centre height for an SLA can be placed virtually anywhere, and is quite near the ground at the front for an ITR. For a McPherson strut, the roll centre is given by the angle of the strut and the lower A-arm, and is not easily changed since the top of the strut is not easily moved except slightly to change camber, and the lower A-arm is mostly parallel to the ground. Thus if the McPherson strut roll centre is higher, and the c.g. height is similar, then the moment arm for a McPherson strut suspension is less than for the ITR's SLA suspension and the elastic weight transfer is less, requiring stiffer springs to keep roll in check. Keeping roll in check keeps camber more constant and makes the tire happy.
However even if the suspension type keeps the roll centre higher and thus the elastic or sprung portion of the weight transfer larger, this just affects the time response of the weight transfer. The unsprung weight transfer happens very quickly, as the only spring is the tire. The geometric weight transfer through the suspension links also happens very quickly, as the shocks are not involved. Only the elastic part of the transfer happens slowly and is controlled by the dampers, springs and sway-bars. But in the end, once enough time has gone by, all of the weight transfer has occurred, the roll angle is fixed, and we are in a steady state, which is independent of suspension type.
For a 2500 lb FWD car with 64% front weight bias, a 20” c.g. height and 70 lb unsprung weight on each corner, and 800 lb springs front, motion ratio of 1.5 and 1200 lb springs rear, motion ratio of 1.35,with no sway bars to make life easy, if the roll centers are at 0” above the ground, the rear inside wheel will lift at 0.8 g’s. The unsprung weight transfer is 22.4 lbs front and 22.8 lbs rear, the geometric weight transfer is 0 lbs front and rear (due to the 0” roll centre height), and the elastic weight transfer is 232.4 lbs front and 430.3 lbs rear, for a total of 254.8 lbs front and 453.1 lbs rear or 708 lbs total, with a suspension roll angle of 1.25 degrees.
On an identical car but with the roll centres raised by 4” front and rear, the unsprung weight transfer is still about 22 lbs at 0.8 g’s, but the weight transfer via the roll centre goes up from 0 lbs geometric to 80.6 lbs front and 41.9 lbs rear, and the elastic weight transfer reduces to 187.2 lbs front and 346.6 lbs rear, for a total front weight transfer of 290.1 lbs and rear weight transfer of 411.4 lbs, giving the same total of 711 lbs (same as 708 lbs except for rounding errors). Now roll angle is reduced to 1.02 degrees, and inside wheel is not quite about to lift, since front weight transfer is now 290 lbs vs. 255 lbs with the lower roll centre. This can be brought back into line by changing spring rates such that rear wheel just lifts at 0.8 g’s.
Adding a 900 lb/in. rear sway bar with a motion ratio of 2.5 reduces roll angle (not total weight transfer). For the 0” roll centre height case, adding a rear bar just increases rear % of weight transfer and lifts wheel even more, while reducing overall body roll to 0.98 degrees. (remembering that weight transfer happens irregardless of roll). For the 4” roll centre case, adding the same rear bar increase rear % of weight transfer and starts to just lift rear wheel, while reducing roll angle to 0.79 degrees.
Now this whole example would have to be adjusted in terms of motion ratios for a real McPhersen strut vs. SLA, but it does show that with a higher roll center as for strut suspensions, the geometric transfer (the fast undamped one) is increased in relation to the elastic transfer (the slower damped one). I just don’t know how one decides on weight transfer balance for corner exit traction and car rotation to get pointed straight before mashing the gas pedal.
12-15-2003, 02:37 PM
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Re: (descartesfool)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I would think they may be using a smaller sway bar then most of us think to use and increase the spring rates to compensate for it.</TD></TR></TABLE>
I have thought about that set up myself, but never tried it. It would be fun to have the extra $$ to get "soft" rear springs with a "big" rear sway bar, then get some lap times. Then change over to insanely stiff rear springs with a "small" rear sway bar and do some more laps to compair times and the feal of the car.
I have thought about that set up myself, but never tried it. It would be fun to have the extra $$ to get "soft" rear springs with a "big" rear sway bar, then get some lap times. Then change over to insanely stiff rear springs with a "small" rear sway bar and do some more laps to compair times and the feal of the car.
12-15-2003, 06:10 PM
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Re: (Catch 22)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Catch 22 »</TD></TR><TR><TD CLASS="quote">
Rear wings
</TD></TR></TABLE>
I remember reading an article in Racecar Engineering regard the Tocatour cars and rear wings on FF layouts. They were saying that the wings might provide a modicum of downforce and are adjustable, but most likely they use them because they make the cars look racier and attract fans, if I remember the article correctly. I will try to find the article when I can.
-Charlie
Rear wings
</TD></TR></TABLE>
I remember reading an article in Racecar Engineering regard the Tocatour cars and rear wings on FF layouts. They were saying that the wings might provide a modicum of downforce and are adjustable, but most likely they use them because they make the cars look racier and attract fans, if I remember the article correctly. I will try to find the article when I can.
-Charlie
12-16-2003, 04:31 AM
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Re: (descartesfool)
a 2500lb car with a 65/35 weight distribution would have an average of ~438lbs on each rear wheel. how can you transfer 453lbs off of an inside rear tire? (i'm ignoring the fact that the left rear carries more static weight then the right rear for simplicities sake) also, you would have to assume there is some type of droop limiter on the rear suspension to get all of the unsprung weight off the tire. and adding a larger rear swaybar wouldn't effect the roll angle at all in the first example you give because as i already pointed out you've already transferred another 20lbs off of a wheel then it carried in a static state.
once the rear wheel leaves the ground the remaining weight transfer has to happen between the front tires. the front tires also become the final limiting factor on terminal roll angle. increasing the rear springs or swaybar beyond the point needed to lift the tire at the maximum cornering force the car can generate only speeds up the rate of lateral weight transfer between the rear axle. ie, makes the car looser at corner entry on high grip surfaces and makes the car difficult to drive in low grip situations.
another interesting side effect is that if the rate of lateral weight transfer between the rear tires is faster, the weight transfer between the front axle has to be slower. this is important for autocrossers mostly. roadracers probably don't even notice it.
nate
once the rear wheel leaves the ground the remaining weight transfer has to happen between the front tires. the front tires also become the final limiting factor on terminal roll angle. increasing the rear springs or swaybar beyond the point needed to lift the tire at the maximum cornering force the car can generate only speeds up the rate of lateral weight transfer between the rear axle. ie, makes the car looser at corner entry on high grip surfaces and makes the car difficult to drive in low grip situations.
another interesting side effect is that if the rate of lateral weight transfer between the rear tires is faster, the weight transfer between the front axle has to be slower. this is important for autocrossers mostly. roadracers probably don't even notice it.
nate
12-16-2003, 09:04 AM
#32
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Re: (.RJ)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ »</TD></TR><TR><TD CLASS="quote">no bumping. </TD></TR></TABLE>
He's not bumping... it's the newest H-T fad... people will make a worthless post so the thread will appear in their recent topics.
He's not bumping... it's the newest H-T fad... people will make a worthless post so the thread will appear in their recent topics.
12-16-2003, 12:28 PM
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Re: (JeffS)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JeffS »</TD></TR><TR><TD CLASS="quote">
He's not bumping... it's the newest H-T fad... people will make a worthless post so the thread will appear in their recent topics.
</TD></TR></TABLE>
And your post is any less worthless? You only posted in this thread to say something about my post, bub. I posted to get some more info on the topic.
Back on topic: In re to what Catch22 said before, my car does lift a lot during tight corners, and I've been told by many VW racers that our cars are actually more balanced during cornering that way.
http://forums.vwvortex.com/zer...77459
Not on Hondas, but it does apply to most FWD in some way.
He's not bumping... it's the newest H-T fad... people will make a worthless post so the thread will appear in their recent topics.
</TD></TR></TABLE>And your post is any less worthless? You only posted in this thread to say something about my post, bub. I posted to get some more info on the topic.
Back on topic: In re to what Catch22 said before, my car does lift a lot during tight corners, and I've been told by many VW racers that our cars are actually more balanced during cornering that way.
http://forums.vwvortex.com/zer...77459
Not on Hondas, but it does apply to most FWD in some way.
12-16-2003, 03:42 PM
#36
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Re: (solo-x)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x »</TD></TR><TR><TD CLASS="quote">a 2500lb car with a 65/35 weight distribution would have an average of ~438lbs on each rear wheel. how can you transfer 453lbs off of an inside rear tire? (i'm ignoring the fact that the left rear carries more static weight then the right rear for simplicities sake) also, you would have to assume there is some type of droop limiter on the rear suspension to get all of the unsprung weight off the tire. and adding a larger rear swaybar wouldn't effect the roll angle at all in the first example you give because as i already pointed out you've already transferred another 20lbs off of a wheel then it carried in a static state.
once the rear wheel leaves the ground the remaining weight transfer has to happen between the front tires. the front tires also become the final limiting factor on terminal roll angle. increasing the rear springs or swaybar beyond the point needed to lift the tire at the maximum cornering force the car can generate only speeds up the rate of lateral weight transfer between the rear axle. ie, makes the car looser at corner entry on high grip surfaces and makes the car difficult to drive in low grip situations.
another interesting side effect is that if the rate of lateral weight transfer between the rear tires is faster, the weight transfer between the front axle has to be slower. this is important for autocrossers mostly. roadracers probably don't even notice it.
nate</TD></TR></TABLE>
I think you should check your calcs. I said 64% front bias, not 65%. Your 20 lb issue is there. Not relevent to the issue. If you want precision, I can accomodate you. If you think adding a rear roll bar won't reduce roll angle, then what do you think it will it do?
once the rear wheel leaves the ground the remaining weight transfer has to happen between the front tires. the front tires also become the final limiting factor on terminal roll angle. increasing the rear springs or swaybar beyond the point needed to lift the tire at the maximum cornering force the car can generate only speeds up the rate of lateral weight transfer between the rear axle. ie, makes the car looser at corner entry on high grip surfaces and makes the car difficult to drive in low grip situations.
another interesting side effect is that if the rate of lateral weight transfer between the rear tires is faster, the weight transfer between the front axle has to be slower. this is important for autocrossers mostly. roadracers probably don't even notice it.
nate</TD></TR></TABLE>
I think you should check your calcs. I said 64% front bias, not 65%. Your 20 lb issue is there. Not relevent to the issue. If you want precision, I can accomodate you. If you think adding a rear roll bar won't reduce roll angle, then what do you think it will it do?
12-16-2003, 03:47 PM
#37
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Re: (solo-x)
It's very interesting reading some of these threads revolving suspensions and theories. As someone whose been road racing for longer than I care to devulge, I'm curious to hear what actual racing experience some of you have. It is a great place to share track experiences. The short answer to the question of why the CTR touring cars don't lift a wheel has to do with 100s of hours of track testing by the world's finest suspension engineers along with an almost unlimited budget. It doesn't come down to something as simple as "heavy springs here" or "a stiffer bar there", but a million adjustments and corrections. I've run the same Dunlop Slicks they run on our SPU CRX, and it took a whole season to get the suspension to work with the incredible grip. I can tell you that the spring rates are off the wall.
Great thread, keep it up.
Great thread, keep it up.
12-16-2003, 04:05 PM
#38
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Re: (daigo)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote"> took a whole season to get the suspension to work with the incredible grip. I can tell you that the spring rates are off the wall.</TD></TR></TABLE>
Off the wall = more than 1500lbs/inch ??
Did you find that making changes to the swar bars helped more than changes to the spring rates or was it the other way? I'm sure it was a combo of both, but I would like to here what you did.
Off the wall = more than 1500lbs/inch ??
Did you find that making changes to the swar bars helped more than changes to the spring rates or was it the other way? I'm sure it was a combo of both, but I would like to here what you did.
12-16-2003, 07:44 PM
#39
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Re: (57STS)
We found as we got closer with our spring rates the better grip we got. The better grip you have in a corner the more that the weight transfers to the outside front corner. The only way to balance this out is increasing the front bar stiffness. The big challenge in the rear is the inherent "steer" designed into the Honda rear suspension, that's why I disagree with a lot of the comments I read above (no offence). The easiest way to combat this is to limit travel in the rear. There are many other things that can be done to lessen the negative effects such as relocating pickup points etc. If one has the opportunity to observe closely the rear suspension on the TOCA CTR you will know there is hardly any travel in the rear of those Hondas.
12-17-2003, 04:22 AM
#40
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Re: (descartesfool)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by descartesfool »</TD></TR><TR><TD CLASS="quote">I think you should check your calcs. I said 64% front bias, not 65%. Your 20 lb issue is there. Not relevent to the issue. If you want precision, I can accomodate you. If you think adding a rear roll bar won't reduce roll angle, then what do you think it will it do?</TD></TR></TABLE>
my calcs are correct, my typing is not. 64% of 2500lbs is 1625. 2500-1625=875. 875/2=437.5. yes, i know the left rear will be carrying somewhere in the neighborhood of 50lbs more static weight then the right rear (depending on balast, etc.) so the left rear is probably somewhere closer to to 462 while the right rear is about 413. *edit* my math is fawked. apparently i can neither type nor use a calculator.
if you don't think 20lbs is relevant to the issue i don't know what to say. in racing we worry about much smaller increments of weight then that.
if my car transfers 100% of the weight off the inside rear at .8 g's and i'm cornering at 1g, where do you think the additional weight transfer is happening? it CAN'T happen between the rear axle pair because there is no longer any weight on the inside rear. where do you think the additional roll resistance is coming from? it CAN'T come from the rear axle pair because one tire was already in the air at .8g's. the rear of the car is now rolling about the outside rear tires contact patch.
similarly, if a 14mm rear bar is sufficient to lift the inside rear at .8g's a 22mm bar will only lift it earlier. terminal roll angle is still defined by the front roll stiffness in this situation. the only way this is not true is if we ignore simple physics and assume we can transfer more weight off the inside rear than it carries in static form.
nate
Modified by solo-x at 6:14 PM 12/17/2003
my calcs are correct, my typing is not. 64% of 2500lbs is 1625. 2500-1625=875. 875/2=437.5. yes, i know the left rear will be carrying somewhere in the neighborhood of 50lbs more static weight then the right rear (depending on balast, etc.) so the left rear is probably somewhere closer to to 462 while the right rear is about 413. *edit* my math is fawked. apparently i can neither type nor use a calculator.
if you don't think 20lbs is relevant to the issue i don't know what to say. in racing we worry about much smaller increments of weight then that.
if my car transfers 100% of the weight off the inside rear at .8 g's and i'm cornering at 1g, where do you think the additional weight transfer is happening? it CAN'T happen between the rear axle pair because there is no longer any weight on the inside rear. where do you think the additional roll resistance is coming from? it CAN'T come from the rear axle pair because one tire was already in the air at .8g's. the rear of the car is now rolling about the outside rear tires contact patch.
similarly, if a 14mm rear bar is sufficient to lift the inside rear at .8g's a 22mm bar will only lift it earlier. terminal roll angle is still defined by the front roll stiffness in this situation. the only way this is not true is if we ignore simple physics and assume we can transfer more weight off the inside rear than it carries in static form.
nate
Modified by solo-x at 6:14 PM 12/17/2003
12-17-2003, 05:56 AM
#41
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Re: (solo-x)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x »</TD></TR><TR><TD CLASS="quote">... the only way this is not true is if we ignore simple physics and assume we can transfer more weight off the inside rear than it carries in static form.
nate </TD></TR></TABLE>
On April 1st 2004 I plan to introduce an amazing new system that among other amazing things does just that.
Scott, who thinks if you're going to let yourself be shackled by "physics" why even bother playing the game....
* I will tell you my R&D process:
...repeat until...until...."I'm working on it!"
nate </TD></TR></TABLE>
On April 1st 2004 I plan to introduce an amazing new system that among other amazing things does just that.
Scott, who thinks if you're going to let yourself be shackled by "physics" why even bother playing the game....
* I will tell you my R&D process:
...repeat until...until...."I'm working on it!"
12-17-2003, 08:49 AM
#42
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Re: (solo-x)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x »</TD></TR><TR><TD CLASS="quote">
my calcs are correct, my typing is not. 64% of 2500lbs is 1625. 2500-1625=875. 875/2=437.5.
nate </TD></TR></TABLE>
My calculator says that 64% of 2500lbs is 1600. 2500-1600=900. 900/2=450 lbs on each rear wheel. My example gave -453 lbs at .8 g's to lift inside rear, which is correct within 3 lbs. More precisely, wheel lifts at 0.7946 g's, where net force is 0 lbs on left rear. However none of this is the point. My example was just to illustrate effect of roll centre height on how the weight transfers. The issue is what have those suspension engineers done to the newer cars to get maximum lap speed with virtually no inside rear lift, while the previous championship winning ITR's in the US series lifted their wheels a lot. I have nothing for or against wheel lift, I just have something for low lap times.
my calcs are correct, my typing is not. 64% of 2500lbs is 1625. 2500-1625=875. 875/2=437.5.
nate </TD></TR></TABLE>
My calculator says that 64% of 2500lbs is 1600. 2500-1600=900. 900/2=450 lbs on each rear wheel. My example gave -453 lbs at .8 g's to lift inside rear, which is correct within 3 lbs. More precisely, wheel lifts at 0.7946 g's, where net force is 0 lbs on left rear. However none of this is the point. My example was just to illustrate effect of roll centre height on how the weight transfers. The issue is what have those suspension engineers done to the newer cars to get maximum lap speed with virtually no inside rear lift, while the previous championship winning ITR's in the US series lifted their wheels a lot. I have nothing for or against wheel lift, I just have something for low lap times.
12-17-2003, 09:13 AM
#43
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Re: (descartesfool)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by descartesfool »</TD></TR><TR><TD CLASS="quote">
My calculator says that 64% of 2500lbs is 1600. 2500-1600=900. 900/2=450 lbs on each rear wheel. My example gave -453 lbs at .8 g's to lift inside rear, which is correct within 3 lbs. More precisely, wheel lifts at 0.7946 g's, where net force is 0 lbs on left rear. However none of this is the point. My example was just to illustrate effect of roll centre height on how the weight transfers. The issue is what have those suspension engineers done to the newer cars to get maximum lap speed with virtually no inside rear lift, while the previous championship winning ITR's in the US series lifted their wheels a lot. I have nothing for or against wheel lift, I just have something for low lap times.</TD></TR></TABLE>
i need to cut my slice of crow. i re-retyped into my calculator, very carefully this time, and sure enough, 64% of 2500 _is_ 1600. i feel rather sheepish now, but other then my math, my previous posts have been sound. increasing rear roll stiffness beyond the point required to transfer 100% of the weight off the inside rear will not effect terminal roll angle in any way. that was the gist of your post that i was attempting to clarify but got clouded by my innability to use a simple device such as a calculator. i apologize to you and the h-t community as a whole.
descartesfool, if i may be so bold as to ask, how did you come to the different weight transfer totals with varying rc heights? i've never fully understood the interelation of roll center height to weight transfer distribution and any insight you can offer would be helpful.
nate
My calculator says that 64% of 2500lbs is 1600. 2500-1600=900. 900/2=450 lbs on each rear wheel. My example gave -453 lbs at .8 g's to lift inside rear, which is correct within 3 lbs. More precisely, wheel lifts at 0.7946 g's, where net force is 0 lbs on left rear. However none of this is the point. My example was just to illustrate effect of roll centre height on how the weight transfers. The issue is what have those suspension engineers done to the newer cars to get maximum lap speed with virtually no inside rear lift, while the previous championship winning ITR's in the US series lifted their wheels a lot. I have nothing for or against wheel lift, I just have something for low lap times.</TD></TR></TABLE>
i need to cut my slice of crow. i re-retyped into my calculator, very carefully this time, and sure enough, 64% of 2500 _is_ 1600. i feel rather sheepish now, but other then my math, my previous posts have been sound. increasing rear roll stiffness beyond the point required to transfer 100% of the weight off the inside rear will not effect terminal roll angle in any way. that was the gist of your post that i was attempting to clarify but got clouded by my innability to use a simple device such as a calculator. i apologize to you and the h-t community as a whole.
descartesfool, if i may be so bold as to ask, how did you come to the different weight transfer totals with varying rc heights? i've never fully understood the interelation of roll center height to weight transfer distribution and any insight you can offer would be helpful.
nate
12-17-2003, 09:47 AM
#44
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Re: (solo-x)
Nate,
weight transfer via roll centres is nicely described in Allan Staniforth's Competition Car Suspension book, Chapter 8 (actually by David Gould). A complete detailed example is there. You can make a spreadsheet and duplicate the results as all equations and steps are given. His treatment is not the only way to arrive at the result, but I think it is good. There are two typos in the book's formulas, one in second line of p.203 (SGR should be 16) and one in first equation line on p.205 (should say TF^2/2xpi instead of TF^2x2xpi). Results are good though. My spreadsheet gave same results as those in book. You will need to study it for a while to get a feel. I don't recall any other books that properly go through this.
weight transfer via roll centres is nicely described in Allan Staniforth's Competition Car Suspension book, Chapter 8 (actually by David Gould). A complete detailed example is there. You can make a spreadsheet and duplicate the results as all equations and steps are given. His treatment is not the only way to arrive at the result, but I think it is good. There are two typos in the book's formulas, one in second line of p.203 (SGR should be 16) and one in first equation line on p.205 (should say TF^2/2xpi instead of TF^2x2xpi). Results are good though. My spreadsheet gave same results as those in book. You will need to study it for a while to get a feel. I don't recall any other books that properly go through this.
12-20-2003, 11:37 PM
#45
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I just saw these pictures from the web and thought about this thread. Looks like EP3s from both big tuners in Japan are picking up the inside rear at the same part of the track in China:
12-21-2003, 02:47 PM
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Re: (Wai)
Wai,
obviously the rear roll stiffness is quite high on those Civics, and similar to what I am used to seeing. I have not seen any equivalent pictures from the BTCC, only the videos on Speed Channel. I just watched another, and it still appeared they were hardly lifting the rear wheel, suggesting a more balanced setup front/rear. Pictures might be more revealing for the BTCC CTR car setups, as possibly the camera angles are not revealing. Maybe someone has some.
obviously the rear roll stiffness is quite high on those Civics, and similar to what I am used to seeing. I have not seen any equivalent pictures from the BTCC, only the videos on Speed Channel. I just watched another, and it still appeared they were hardly lifting the rear wheel, suggesting a more balanced setup front/rear. Pictures might be more revealing for the BTCC CTR car setups, as possibly the camera angles are not revealing. Maybe someone has some.
12-21-2003, 02:51 PM
#47
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Re: (descartesfool)
Allow me to advance a mischevious theory.
What we are seeing is something akin to the Coreolis effect.
Whatever is happening in the JDM Hemisphere, it's opposite will take place in the US/UK Hemisphere.
Scott, who knew there was a scientific explanation!
What we are seeing is something akin to the Coreolis effect.
Whatever is happening in the JDM Hemisphere, it's opposite will take place in the US/UK Hemisphere.
Scott, who knew there was a scientific explanation!
12-21-2003, 08:00 PM
#48
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Re: (RR98ITR)
Nope, toilets swirl the same way in Japan, UK, and here. No if the cars were in South America or Australia, then that would explain everything. Maybe it's the left hand, right hand drive thing.
Maybe we full figured American drivers put too much weight on the front end and the smaller Asians don't.
There is some place in Sportscar that advertises a suspension setup that does not use anti-roll bars at all. I wonder how that would effect the whole tire lifting thing?
Maybe we full figured American drivers put too much weight on the front end and the smaller Asians don't.
There is some place in Sportscar that advertises a suspension setup that does not use anti-roll bars at all. I wonder how that would effect the whole tire lifting thing?
09-27-2010, 10:20 PM
#49
Homosexual by choice
Re: BTCC Honda Civic Typr R nary lifts a rear wheel - why?
I was using google for some super touring car information and this thread was in the results. At first i thought it was dated 2008 but a closer inspection reveal it's a 3 not an 8 . This thread is kind of old... wow. Yet seven years later the 3 leg or not discussion continues in many other modern threads. :-) 
I'd have to say though, the super touring technologies is so crazy. The battles between the works team and huge budget with F1 backing (in certain years) resulted in some insane machines. I wish there was a giant book that contains all the secret sauce information and photo **** for everyone to lust. Does such a BTCC book exist?
I'd have to say though, the super touring technologies is so crazy. The battles between the works team and huge budget with F1 backing (in certain years) resulted in some insane machines. I wish there was a giant book that contains all the secret sauce information and photo **** for everyone to lust. Does such a BTCC book exist?
09-27-2010, 10:47 PM
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Re: BTCC Honda Civic Typr R nary lifts a rear wheel - why?
I've been fighting this 4 tire vs. 3 tire dilemma all year. I needed to put the power down at apex and corner exit but I could get the car to rotate TOWARD apex with lots of trail braking (allowing me to brake very deep).
Well, I did what many people do. I put on the big rear sway bar and as a result I was lifting the inside rear tire off the ground. The thing was snap oversteer and frightful to drive and my times weren't any faster... Oh yea, I still pushed under accel and at apex.
I removed the front swaybar and reverted to the stock rear sway and all my problems were solved. Inside rear stays on the ground, the car rotates and can be trail braked but NOW it grips like the dickens at apex and corner exit.
I still need to read up on how front sway bars ever help FWD cars because I can't figure out why they would and it did a world of good to remove mine!
Well, I did what many people do. I put on the big rear sway bar and as a result I was lifting the inside rear tire off the ground. The thing was snap oversteer and frightful to drive and my times weren't any faster... Oh yea, I still pushed under accel and at apex.
I removed the front swaybar and reverted to the stock rear sway and all my problems were solved. Inside rear stays on the ground, the car rotates and can be trail braked but NOW it grips like the dickens at apex and corner exit.
I still need to read up on how front sway bars ever help FWD cars because I can't figure out why they would and it did a world of good to remove mine!