howard coleman's FD Chassis/Setup
01-30-08, 03:50 PM
#51
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-Andy
01-30-08, 04:06 PM
#52
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yeah howard that's the one. It's the RE-Amemiya GT II wing. Im also running a diffuser on the car.
But the car does not realy feel loose, it has a hell of alot of grip. The sidway grip is just sick. And the car does not roll at all. ppl that see the car racing says that it's sick to look at since it don't roll at all.
One of the turns on the local track is a long right turn that goes 180 degrees around. The problem im having is understearing when i hit the gas to accelerate out of the corner. Now im hitting about 70mph out of the corner, but i should be hitting about 85-90mph with the car.
There is also a 110 degree turn after a long streatch where i hit about 115mph, where i hafto get down to 2 gear and about 5000 rpm to get trough the turn. Since the car will understear into the corner. And will oversteer out of the corner due to the way the corner is.
Here is a link to some pics of the track so u can understand the track.
http://www.rudskogen.no/asp/sider.as...ID=33&sideID=0
It's run clockwise
JT
But the car does not realy feel loose, it has a hell of alot of grip. The sidway grip is just sick. And the car does not roll at all. ppl that see the car racing says that it's sick to look at since it don't roll at all.
One of the turns on the local track is a long right turn that goes 180 degrees around. The problem im having is understearing when i hit the gas to accelerate out of the corner. Now im hitting about 70mph out of the corner, but i should be hitting about 85-90mph with the car.
There is also a 110 degree turn after a long streatch where i hit about 115mph, where i hafto get down to 2 gear and about 5000 rpm to get trough the turn. Since the car will understear into the corner. And will oversteer out of the corner due to the way the corner is.
Here is a link to some pics of the track so u can understand the track.
http://www.rudskogen.no/asp/sider.as...ID=33&sideID=0
It's run clockwise
JT
01-30-08, 04:12 PM
#53
Rotary Enthusiast
I would think that all else being equal your setup would be a bit tail happy, so strange that you have a bad push. Have you run without the wing just to see? Your tire stagger is not that large, but 9 to 11 inch wheels is a pretty big stagger. Personally, I'd go with larger wheels and tires in the front. Other than that, and you've probably already checked it, but I'd make sure something isn't binding or bottoming out in the front suspension. If you are leaning on a front bumpstop in corners, it will push when the spring rate skyrockets. That's assuming you have a relatively stiff bumpstop and not a soft progressive one.
-Andy
-Andy
I have not tried running the car without the wing. But i have tried running it without the diffuser tho, and that did help alittle on the understear.
I know about the front rims. Im gonna go down to 17" and go up to 10" wide in the front. But having a hard time finding 11x17" rims. I want to go down on the size of the rims to get more rubber.
JT
01-30-08, 05:13 PM
#54
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That's the thing, it's not tail happy at all. When i flor it in first it i get some wheelspin but not alot. In 2nd gear im not getting any wheelspin at all, unless it's out of a corner and the car is not stable. But that rearly happens too.
I have not tried running the car without the wing. But i have tried running it without the diffuser tho, and that did help alittle on the understear.
I know about the front rims. Im gonna go down to 17" and go up to 10" wide in the front. But having a hard time finding 11x17" rims. I want to go down on the size of the rims to get more rubber.
JT
I have not tried running the car without the wing. But i have tried running it without the diffuser tho, and that did help alittle on the understear.
I know about the front rims. Im gonna go down to 17" and go up to 10" wide in the front. But having a hard time finding 11x17" rims. I want to go down on the size of the rims to get more rubber.
JT
I have 17x11.5 rims in front from www.bogartracingwheels.com that are reasonably priced, 3 piece and lightweight. Not sure if he ships to you or not, might be too expensive at that point. I use the RR10 style (most of their stuff are for drag use). You can spec what backspace you want and width. If you were in the US, I would expect 17x10 or 11's to be about 500-600 each, and weigh aroud 16.5lbs.
-Andy
01-30-08, 08:26 PM
#56
Racing Rotary Since 1983
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"understeering when i hit the gas to accelerate out of the corner"
as soon as you get on the gas you transfer weight to the rear. if, for example, you transfer 200 pounds to the rear you it comes from the front. the front tires are on the left side of their cohesion curve and offer less grip w less weight.
if you were running less overall spring rate you would be better able to manage this balancing act. your springs are 860 pounds and your corner weight is around 770. flowed thru the motion ratio i don't see 1.5 inches of travel which must make the car difficult to drive on the edge. the only reason your rear isn't all over the place is your rear Aero downforce.
and yes, as Andy posts- you could go up a touch on the front rubber.
BTW, whomever designed your track is diabolical. both the first and last turns are lefts.... real road racing cars are set up to favor right turns as there are always more rights than lefts if you run clockwise as most tracks lay out. my racecar had a couple hundred pounds of lead in the right side framerail. the problem is you do give up in left hand turns. when a key left is the first turn you find yourself on cold tires w a bunch of cars behind you heading for a turn where the car isn't particularly happy. it makes for interesting spectating.
for example Mid Ohio has turn one to the left, is off camber and blind w a bridge. now that i think of it the last turn is a left also.
just one other point re driving... presumably you are at the edge of your friction circle on your tires in a steady state corner just as you get on the gas. at that point you must widen the turn in order to accelerate or your rear tires will spin. widening the turn allows the rears to add the second force vector: acceleration. if a person hammers it while at the edge of cohesion the car will oversteer immediately. generally, an easy way to widen a turn is to use an early apex.
Hey damian... i imagine you are itching for the snow to melt... what have you got cooking for 08?
hc
as soon as you get on the gas you transfer weight to the rear. if, for example, you transfer 200 pounds to the rear you it comes from the front. the front tires are on the left side of their cohesion curve and offer less grip w less weight.
if you were running less overall spring rate you would be better able to manage this balancing act. your springs are 860 pounds and your corner weight is around 770. flowed thru the motion ratio i don't see 1.5 inches of travel which must make the car difficult to drive on the edge. the only reason your rear isn't all over the place is your rear Aero downforce.
and yes, as Andy posts- you could go up a touch on the front rubber.
BTW, whomever designed your track is diabolical. both the first and last turns are lefts.... real road racing cars are set up to favor right turns as there are always more rights than lefts if you run clockwise as most tracks lay out. my racecar had a couple hundred pounds of lead in the right side framerail. the problem is you do give up in left hand turns. when a key left is the first turn you find yourself on cold tires w a bunch of cars behind you heading for a turn where the car isn't particularly happy. it makes for interesting spectating.
for example Mid Ohio has turn one to the left, is off camber and blind w a bridge. now that i think of it the last turn is a left also.
just one other point re driving... presumably you are at the edge of your friction circle on your tires in a steady state corner just as you get on the gas. at that point you must widen the turn in order to accelerate or your rear tires will spin. widening the turn allows the rears to add the second force vector: acceleration. if a person hammers it while at the edge of cohesion the car will oversteer immediately. generally, an easy way to widen a turn is to use an early apex.
Hey damian... i imagine you are itching for the snow to melt... what have you got cooking for 08?
hc
01-31-08, 02:00 AM
#57
>>Hey damian... i imagine you are itching for the snow to melt... what have you got cooking for 08?
Yes i am :-)
The only thing I plan to change is the biggest weakness on the car currently..... the stock gear ratios. I do not have a big budget to work with, but I think I can do a t5 dogring setup from gforce, with much better road racing ratios, keeping the shifts between 6.2K and 8K for most gears :-)
Yes i am :-)
The only thing I plan to change is the biggest weakness on the car currently..... the stock gear ratios. I do not have a big budget to work with, but I think I can do a t5 dogring setup from gforce, with much better road racing ratios, keeping the shifts between 6.2K and 8K for most gears :-)
01-31-08, 04:07 AM
#58
Rotary Enthusiast
How much power do you have now? I'm not sure with decent tires what you are describing is unusual. I can flat foot my car off of most corners in 2nd with s 4.77 rear gear (with about 400rwhp and 335 tires). Does it push everywhere in the corner? On the brakes going in? Mid corner? Hard on throttle on the exit?
I have 17x11.5 rims in front from www.bogartracingwheels.com that are reasonably priced, 3 piece and lightweight. Not sure if he ships to you or not, might be too expensive at that point. I use the RR10 style (most of their stuff are for drag use). You can spec what backspace you want and width. If you were in the US, I would expect 17x10 or 11's to be about 500-600 each, and weigh aroud 16.5lbs.
-Andy
I have 17x11.5 rims in front from www.bogartracingwheels.com that are reasonably priced, 3 piece and lightweight. Not sure if he ships to you or not, might be too expensive at that point. I use the RR10 style (most of their stuff are for drag use). You can spec what backspace you want and width. If you were in the US, I would expect 17x10 or 11's to be about 500-600 each, and weigh aroud 16.5lbs.
-Andy
I would say it pushes almost in the entire corner. It feels like the rear end is holding the car back. And it wont let the front end turn in at higher speeds.
I know alot of this could be fixed with tweaking the setup alot more. Wich im planing on doing.
Il need to look into finding some wheels that i like in 17" to get some more rubber on the tires. Cause i have small feeling that the 18" tires has to low rubber wall to be fast.
JT
01-31-08, 04:12 AM
#59
Rotary Enthusiast
JT
01-31-08, 12:55 PM
#60
>>I would say it pushes almost in the entire corner. It feels like the rear end is holding the car back. And it wont let the front end turn in at higher speeds.
Hmm, that sounds exactly the oppostite of how I have my track car setup :-)
My car never pushed, the front will always turn in, and I make tweaks to keep the rear in check as needed. Even through all the changes I have made to the car, it always has been setup like that, as I like to have a slight oversteer condition rahter than understeer.
Maybe somene asked already, but are you trail braking into the corner? If you do not trail and keep weight on the front the car will want to push.
Since I have no ABS, I have to be carefull when I trail brake hard or the inside tires will lock (no weight on them on turn in, especially the rear inside tire), but trailing properly allows you to really control how the car rotates through the turn.
Hmm, that sounds exactly the oppostite of how I have my track car setup :-)
My car never pushed, the front will always turn in, and I make tweaks to keep the rear in check as needed. Even through all the changes I have made to the car, it always has been setup like that, as I like to have a slight oversteer condition rahter than understeer.
Maybe somene asked already, but are you trail braking into the corner? If you do not trail and keep weight on the front the car will want to push.
Since I have no ABS, I have to be carefull when I trail brake hard or the inside tires will lock (no weight on them on turn in, especially the rear inside tire), but trailing properly allows you to really control how the car rotates through the turn.
02-01-08, 01:06 PM
#63
Rotary Enthusiast
>>I would say it pushes almost in the entire corner. It feels like the rear end is holding the car back. And it wont let the front end turn in at higher speeds.
Hmm, that sounds exactly the oppostite of how I have my track car setup :-)
My car never pushed, the front will always turn in, and I make tweaks to keep the rear in check as needed. Even through all the changes I have made to the car, it always has been setup like that, as I like to have a slight oversteer condition rahter than understeer.
Maybe somene asked already, but are you trail braking into the corner? If you do not trail and keep weight on the front the car will want to push.
Since I have no ABS, I have to be carefull when I trail brake hard or the inside tires will lock (no weight on them on turn in, especially the rear inside tire), but trailing properly allows you to really control how the car rotates through the turn.
Hmm, that sounds exactly the oppostite of how I have my track car setup :-)
My car never pushed, the front will always turn in, and I make tweaks to keep the rear in check as needed. Even through all the changes I have made to the car, it always has been setup like that, as I like to have a slight oversteer condition rahter than understeer.
Maybe somene asked already, but are you trail braking into the corner? If you do not trail and keep weight on the front the car will want to push.
Since I have no ABS, I have to be carefull when I trail brake hard or the inside tires will lock (no weight on them on turn in, especially the rear inside tire), but trailing properly allows you to really control how the car rotates through the turn.
But before we continue, could u explain what trail braking is? Since im not sure what it means in norwegian. I can translate it, but it kinda don't make sense.
JT
02-02-08, 05:45 AM
#66
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02-02-08, 10:32 PM
#67
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JT,
It might help to eliminate some of the driver variable and run the car on a skidpad. If you have terminal understeer there, that might mean you have a fundamental balance or alignment problem.
-Andy
It might help to eliminate some of the driver variable and run the car on a skidpad. If you have terminal understeer there, that might mean you have a fundamental balance or alignment problem.
-Andy
02-03-08, 12:54 PM
#68
Rotary Enthusiast
Were gonna test alot this summer and see if we can figure out what it is. Im also gonna do a few things. Like give it more downforce in the front. But where also gonna check everything with the suspension and redo the entire suspension setup on it again. To get everything right again.
Now i just need to get the car together again, at the moment it's stripped down, after beeing painted white
JT
02-03-08, 01:02 PM
#69
Rotary Enthusiast
JT
02-03-08, 01:26 PM
#70
^^^^
That would be ground up, to the fender lips. I've got mine at 25.25"... you'll be surprised at how accurate a set up aspect that is. I had the car corner weighted, and it was almost spot-on, just from getting the heights even.
With regard to your handling problem, I would start to test tire temps across the tire, or just try some camber adjustments and see how they affect it. I've found that these cars are very sensitive to camber adjustments, especially the wider you go with the tire.
That would be ground up, to the fender lips. I've got mine at 25.25"... you'll be surprised at how accurate a set up aspect that is. I had the car corner weighted, and it was almost spot-on, just from getting the heights even.
With regard to your handling problem, I would start to test tire temps across the tire, or just try some camber adjustments and see how they affect it. I've found that these cars are very sensitive to camber adjustments, especially the wider you go with the tire.
02-06-08, 05:14 PM
#72
Racing Rotary Since 1983
Thread Starter
iTrader: (6)
Tein coil over info...
i have had numerous requests as to our options re the Tein coil over lines so i finally got around (blizzard today) to dialing them up.
Tein serves up anything from the "Basic" setup at $780 non adjustable to rocket science stuff around $2500.
as i previously posted, there are many ways to get it done. i indicated that the spring rate was item number one.
stiffer springs do NOT transfer less lateral weight. they do speed up the transfer process making it MORE difficult to drive on the edge of traction. various vendors equate stiff rates with.... stiff body parts i guess.
i don't.
simply put... run either 8 KG fr 6 KG rear or max 10/8.
Tein offers 3 reasonably priced options.
Basic $780. not adjustable as to the shock valving. adj ride height. they come w 12/10. entirely unacceptable spring rate.
Super Street (my choice) $1040. 16 clicks adj shock valving. i dynoed these and the valving delivers anything you want. 12/10 springs, again unacceptable. the SS has a tapered spring so it fits the OEM upper mount which i strongly recommend over a steel upper pillowball mount. yippie!
Flex $1580. steel upper mount. since the upper mount does NOTHING in re to geometry and greatly increases NVH i will pass. 16 adj. a separate height adj which is an interesting concept but since the SS has no problems bottoming out the shock at 25 inch ride height who needs it.
my recommendation is buy the SS and order different springs.
Tein has some in stock so the early bird gets them and the late bird waits....
i recommend the 8 front 6 rear or 10 front and 8 rear.
there are, of course, lots of other brands. get the spring rate correct and you are more than half way home.
hc
i have had numerous requests as to our options re the Tein coil over lines so i finally got around (blizzard today) to dialing them up.
Tein serves up anything from the "Basic" setup at $780 non adjustable to rocket science stuff around $2500.
as i previously posted, there are many ways to get it done. i indicated that the spring rate was item number one.
stiffer springs do NOT transfer less lateral weight. they do speed up the transfer process making it MORE difficult to drive on the edge of traction. various vendors equate stiff rates with.... stiff body parts i guess.
i don't.
simply put... run either 8 KG fr 6 KG rear or max 10/8.
Tein offers 3 reasonably priced options.
Basic $780. not adjustable as to the shock valving. adj ride height. they come w 12/10. entirely unacceptable spring rate.
Super Street (my choice) $1040. 16 clicks adj shock valving. i dynoed these and the valving delivers anything you want. 12/10 springs, again unacceptable. the SS has a tapered spring so it fits the OEM upper mount which i strongly recommend over a steel upper pillowball mount. yippie!
Flex $1580. steel upper mount. since the upper mount does NOTHING in re to geometry and greatly increases NVH i will pass. 16 adj. a separate height adj which is an interesting concept but since the SS has no problems bottoming out the shock at 25 inch ride height who needs it.
my recommendation is buy the SS and order different springs.
Tein has some in stock so the early bird gets them and the late bird waits....
i recommend the 8 front 6 rear or 10 front and 8 rear.
there are, of course, lots of other brands. get the spring rate correct and you are more than half way home.
hc
Last edited by Howard Coleman; 04-16-08 at 01:19 PM.
02-06-08, 06:06 PM
#73
I think u nicked my problem almost spot on Damian. I have the problem of locking the inner front tire. Well now i should say i have verry little breaking power on the front wheels.
But before we continue, could u explain what trail braking is? Since im not sure what it means in norwegian. I can translate it, but it kinda don't make sense.
JT
But before we continue, could u explain what trail braking is? Since im not sure what it means in norwegian. I can translate it, but it kinda don't make sense.
JT
http://www.amazon.com/Speed-Secrets-...2342622&sr=8-1
(See attachments)
If you have more questions on trail braking, lets take it to a different thread so we do not hijack Howard's thread with to much of this.
Last edited by damian; 02-06-08 at 06:25 PM.
02-07-08, 03:31 PM
#74
Based upon Howards recommendations I just purchased Tein SS coilovers and ordered the optional Tein Springs rated at 8kg front and 6kg rear.
Ordered the Tein SS Coilovers from www.prostreetonline.com for $839.00 shipped.
Ordered the Tein Springs from www.group5motorsport.com for $298.00 shipped.
Great pricing on the Tein SS's! The Tein Springs you are limited by availablity, so you pay their price listed.
Thanks Howard!
Ordered the Tein SS Coilovers from www.prostreetonline.com for $839.00 shipped.
Ordered the Tein Springs from www.group5motorsport.com for $298.00 shipped.
Great pricing on the Tein SS's! The Tein Springs you are limited by availablity, so you pay their price listed.
Thanks Howard!
02-07-08, 10:48 PM
#75
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Howard,
This is a GREAT thread and gets a lot of real world things on the table that should help just everyone looking to take their car to the track. I hope it becomes a sticky
93silverbullet,
That is a great price!
---
My only question would be regarding the twin tube design vs. mono tube. Would anyone care to explain the mono advantage?
---
Don't forget that before the corner you should have a solid set of racing brakes and track pads to slow you down.
This is a GREAT thread and gets a lot of real world things on the table that should help just everyone looking to take their car to the track. I hope it becomes a sticky
93silverbullet,
That is a great price!
---
My only question would be regarding the twin tube design vs. mono tube. Would anyone care to explain the mono advantage?
---
Don't forget that before the corner you should have a solid set of racing brakes and track pads to slow you down.
