howard coleman's FD Chassis/Setup
02-15-10, 10:45 PM
#651
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Howard,
The car is definitely more than a handful at the track. as you can see, I was spinning in 3rd gear. I can't tell if the splitter did anything since it was so cold at the track. I'm hoping to at least gain just a little more downforce up front so that I can actually brake better. As for the rear, I added 3 more degrees on my rear spoiler. My next project is to finish up the under panel for the rest of the chassis and adding a diffuser/under spoiler for the car. My current fuel setup is 1300/1600 and I'm maxed out at 6700rpm. Looks like I'll need 3 fuel pumps to support my engine need.
I'll keep you updated once I get more track time with the car.
The car is definitely more than a handful at the track. as you can see, I was spinning in 3rd gear. I can't tell if the splitter did anything since it was so cold at the track. I'm hoping to at least gain just a little more downforce up front so that I can actually brake better. As for the rear, I added 3 more degrees on my rear spoiler. My next project is to finish up the under panel for the rest of the chassis and adding a diffuser/under spoiler for the car. My current fuel setup is 1300/1600 and I'm maxed out at 6700rpm. Looks like I'll need 3 fuel pumps to support my engine need.
I'll keep you updated once I get more track time with the car.
once you get the car dialed NO ONE is going to touch you on a road course. a 550 rwhp FD? supersonic.
as mentioned in post one of this thread the ultimate challenge on the FD as lap times drop is hooking up the rear end. and, of course as hp goes up that challenge becomes greater.
race tires don't work at less than 140 degrees and i am sure in the video you hadn't quite reached that point. combined w axle bending torque you must have been very busy
i am concerned about the splitter. given the need to add rear grip w alot more ponies the splitter loads the front quite a bit. if you load the front you unload the back. i don't know if you are running a rear spoiler but you will need one w that splitter. further, when you start adding downforce the primary spring function changes to resisting downforce and maintaining rideheight to offset camber gain.
you will be busy this year but the car has awesome potential.
BTW, i really like the idea of running alcohol (E85). road racing is so demanding on our 159 cu inch motors especially when they are pumped up w alot of air. the cumulative thermal effect of running a number of laps presents a serious challenge.
nothing provides the cooling of alcohol.
i will be attempting to break 200 mph at the Texas Mile in oct and will be running straight methanol. i figure the mile will take around 25+ seconds and it will require around 600 rw to get it done. that's alot of stress and methanol will give the motor the best chance of surviving.
on another note... and again re-enforcing something from post one... i noticed a crew chief at yesterday's Daytona 500 saying that they had been going back and forth changing Biffle's tires by two tenths of a pound of air!
that underscores how important the right tire pressure is. and you can only figure it out w a pyrometer.
good luck in 2010 Steve!
howard
as mentioned in post one of this thread the ultimate challenge on the FD as lap times drop is hooking up the rear end. and, of course as hp goes up that challenge becomes greater.
race tires don't work at less than 140 degrees and i am sure in the video you hadn't quite reached that point. combined w axle bending torque you must have been very busy
i am concerned about the splitter. given the need to add rear grip w alot more ponies the splitter loads the front quite a bit. if you load the front you unload the back. i don't know if you are running a rear spoiler but you will need one w that splitter. further, when you start adding downforce the primary spring function changes to resisting downforce and maintaining rideheight to offset camber gain.
you will be busy this year but the car has awesome potential.
BTW, i really like the idea of running alcohol (E85). road racing is so demanding on our 159 cu inch motors especially when they are pumped up w alot of air. the cumulative thermal effect of running a number of laps presents a serious challenge.
nothing provides the cooling of alcohol.
i will be attempting to break 200 mph at the Texas Mile in oct and will be running straight methanol. i figure the mile will take around 25+ seconds and it will require around 600 rw to get it done. that's alot of stress and methanol will give the motor the best chance of surviving.
on another note... and again re-enforcing something from post one... i noticed a crew chief at yesterday's Daytona 500 saying that they had been going back and forth changing Biffle's tires by two tenths of a pound of air!
that underscores how important the right tire pressure is. and you can only figure it out w a pyrometer.
good luck in 2010 Steve!
howard
02-16-10, 10:20 AM
#652
Racing Rotary Since 1983
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here's how i see your fuel at 550 rwhp...
assuming you run a 11 to 1 AFR:
550 rwRotaryhp requires 1.92 CFM per hp. 550 X 1.92 = 1056 CFM
1056 CFM/ 14.471 = 73 pounds per minute of air
at 11 AFR that's be 73/11 = 6.636 pounds of gasoline
6.636/ 6.35 = 1.045 gallons per minute
1.045 GPM X 116,090 = 121,325 BTUs to make 550 at 11 AFR
Gasoline..................................116,090 BTUs per gallon
Ethanol......................................76,33 0
E85............................................82, 293
121,325/82,293 = 1.473 GPM of E85 to make 550 rwRhp
1.473 = 5576 CC/Min
to correct for running injectors at no more than 85% duty:
5576 X 1.176 = 6557 total Nominal injector capacity needed at 11 AFR 550 rwRhp.
maybe switch in a set of Injector Dynamics 2200s
how about a Kenne Bell Boost A Pump? i have run mine since 99 on the same Cosmo pump.
let's not overlook the immense cooling from alcohol:
BTUs of COOLING per gallon:
gasoline.......................952
ethanol.......................2398
E85.............................2181
methanol....................3136
gasoline 1.045 GPM = 995 cooling BTUs
E85 1.473 GPM = 3213 cooling BTUs
note methanol's cooling.... that's why methanol, not ethanol is found in extremely serious racecars.
chassis: i didn't know you had a rear spoiler... that will help trim your splitter. i would absolutely run a set of tie wraps on my shock rods to see what your travel is...
howard
assuming you run a 11 to 1 AFR:
550 rwRotaryhp requires 1.92 CFM per hp. 550 X 1.92 = 1056 CFM
1056 CFM/ 14.471 = 73 pounds per minute of air
at 11 AFR that's be 73/11 = 6.636 pounds of gasoline
6.636/ 6.35 = 1.045 gallons per minute
1.045 GPM X 116,090 = 121,325 BTUs to make 550 at 11 AFR
Gasoline..................................116,090 BTUs per gallon
Ethanol......................................76,33 0
E85............................................82, 293
121,325/82,293 = 1.473 GPM of E85 to make 550 rwRhp
1.473 = 5576 CC/Min
to correct for running injectors at no more than 85% duty:
5576 X 1.176 = 6557 total Nominal injector capacity needed at 11 AFR 550 rwRhp.
maybe switch in a set of Injector Dynamics 2200s
how about a Kenne Bell Boost A Pump? i have run mine since 99 on the same Cosmo pump.
let's not overlook the immense cooling from alcohol:
BTUs of COOLING per gallon:
gasoline.......................952
ethanol.......................2398
E85.............................2181
methanol....................3136
gasoline 1.045 GPM = 995 cooling BTUs
E85 1.473 GPM = 3213 cooling BTUs
note methanol's cooling.... that's why methanol, not ethanol is found in extremely serious racecars.
chassis: i didn't know you had a rear spoiler... that will help trim your splitter. i would absolutely run a set of tie wraps on my shock rods to see what your travel is...
howard
Last edited by Howard Coleman; 02-17-10 at 11:48 AM.
02-16-10, 06:46 PM
#654
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great info howard. I have two bosch 044 pumps. One to supply fuel to the surge tank, the other supply fuel to the engine. I'm thinking about running the aeromotive 1000 to the surge tank, then both bosch to the engine. I think that should supply enough fuel for my setup. I know my turbo is maxed so I'm pretty happy with the current level.
02-26-10, 10:27 AM
#655
sorry to move the thread away from its current direction of fueling and such...
Matt
02-26-10, 11:22 AM
#656
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"Is it just a way too overdamped setup?"
yes. but it is only in one direction. i forget whether is was bump or rebound. i do have the reads from my shock dyno but not immediately available.
i suggest that for many swapping out the springs and running stock (non R1) shocks works really well.
i have received over 25 PMs from guys that agree after making the swap.
don't forget tire pressures and proper alignment.
good luck,
howard
yes. but it is only in one direction. i forget whether is was bump or rebound. i do have the reads from my shock dyno but not immediately available.
i suggest that for many swapping out the springs and running stock (non R1) shocks works really well.
i have received over 25 PMs from guys that agree after making the swap.
don't forget tire pressures and proper alignment.
good luck,
howard
03-12-10, 02:45 AM
#657
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Howard,
I have some questions regarding corner balancing. I just corner weighted my car and attempted to corner balance it. Here're my results.
684 580
782 678
This is with me sitting in the driver seat and full tank of gas (25gal). No matter what I do to the front and rear, I couldn't get the F/R balance to within 50lbs (currently is around 47/53). I was able to get the cross weight to 50/50 (which I think is important.).
My current height for front is approx 26.3in (fender to gnd) and rear 24.9in (fender to gnd). Do you have any suggestion on what else I can do w/o putting any ballast to the passenger side?
Since I'm running 320 rear and 280 front tires, do you think that will offset the slight oversteering I may encounter?
I'm racing this weekend so I will get a better feel of the car but I figure I would ask you if there's anything I can do before the weekend.
Also, Now that I know what my car weight with me, I don't need to detune the car as much as I needed to meet the 5.50. based on my calculation, I can have up to 490rwhp which is about 60rwhp less than what I'm currently making. I should be able to detune it to meet the requirement.
I have some questions regarding corner balancing. I just corner weighted my car and attempted to corner balance it. Here're my results.
684 580
782 678
This is with me sitting in the driver seat and full tank of gas (25gal). No matter what I do to the front and rear, I couldn't get the F/R balance to within 50lbs (currently is around 47/53). I was able to get the cross weight to 50/50 (which I think is important.).
My current height for front is approx 26.3in (fender to gnd) and rear 24.9in (fender to gnd). Do you have any suggestion on what else I can do w/o putting any ballast to the passenger side?
Since I'm running 320 rear and 280 front tires, do you think that will offset the slight oversteering I may encounter?
I'm racing this weekend so I will get a better feel of the car but I figure I would ask you if there's anything I can do before the weekend.
Also, Now that I know what my car weight with me, I don't need to detune the car as much as I needed to meet the 5.50. based on my calculation, I can have up to 490rwhp which is about 60rwhp less than what I'm currently making. I should be able to detune it to meet the requirement.
03-13-10, 07:30 AM
#658
Racing Rotary Since 1983
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good luck this weekend.
congrats on getting so much rear weight. i run 53% rear weight w a 1/2 tank gas. the more rear weight the faster a front engine rear drive high powered car goes. it is all about hooking up the rear so you can put the power down earlier than the other guy in the corner. plus you have alot of power to hook up.
if there is any way to get your outside weight down that'd be the next move. you have 53.8% outside weight w a full tank. i ran 43% w my GT3 car.
generally, the best way to control dynamic weight is by adjusting static weight, i e moving components and removing components.
i assume your highish front ride height is due to tire clearance? i would find a way to get the front down to 25. big payback along w less outside weight. (assumes your track is clockwise)
envious of you out this weekend.
howard
congrats on getting so much rear weight. i run 53% rear weight w a 1/2 tank gas. the more rear weight the faster a front engine rear drive high powered car goes. it is all about hooking up the rear so you can put the power down earlier than the other guy in the corner. plus you have alot of power to hook up.
if there is any way to get your outside weight down that'd be the next move. you have 53.8% outside weight w a full tank. i ran 43% w my GT3 car.
generally, the best way to control dynamic weight is by adjusting static weight, i e moving components and removing components.
i assume your highish front ride height is due to tire clearance? i would find a way to get the front down to 25. big payback along w less outside weight. (assumes your track is clockwise)
envious of you out this weekend.
howard
03-13-10, 09:35 AM
#659
Steve,
Your fender height measurements may be skewed due to the Pettit flares, as if you had that much higher a front, you'd have bigger problems, particularly w/ a rear wing.
Sounds like you could go lower, but I know you run road racing slicks that I believe are taller. You might try disconnecting the sway bars and rechecking... if there's some pre-load in them, it could be difficult to jack the weight around w/ coilovers.
Your fender height measurements may be skewed due to the Pettit flares, as if you had that much higher a front, you'd have bigger problems, particularly w/ a rear wing.
Sounds like you could go lower, but I know you run road racing slicks that I believe are taller. You might try disconnecting the sway bars and rechecking... if there's some pre-load in them, it could be difficult to jack the weight around w/ coilovers.
03-14-10, 02:01 PM
#660
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Howard,
I placed 2nd in TTU yesterday. The car was detuned to 410rwhp to meet the TTU class. The car is definitely too low at the back. You can hear the tire hitting the chassis when taken a left turn. I also felt a little understeer at turn. Maybe I need to put some weight to the front?
Here's a video of my car. I'm still trying to download the rest so I'll post them later.
http://s371.photobucket.com/albums/o..._converted.flv
I placed 2nd in TTU yesterday. The car was detuned to 410rwhp to meet the TTU class. The car is definitely too low at the back. You can hear the tire hitting the chassis when taken a left turn. I also felt a little understeer at turn. Maybe I need to put some weight to the front?
Here's a video of my car. I'm still trying to download the rest so I'll post them later.
http://s371.photobucket.com/albums/o..._converted.flv
03-14-10, 02:20 PM
#661
Crap Steve.... the video stops just after you cleared the pack. Guessing you must have busted a high 120s on the last lap. Looks like fun. Hope all is well. Nice to see you chewing up those Vets and Porsches. How does the car run on E85??
Tim
Tim
03-14-10, 02:35 PM
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I just saw the video upload to the web. it's missing 4 mins of the clip. I wonder if there's a 10min limit. I ran a 1:20.1s on that lap. The car runs great other than cold start issues... Now i just need to figure out which pump is going bad causing low fuel pressure.... I think my aeromotive is crapping out...
Here's a pic of my fuel system...
Here's a pic of my fuel system...
Last edited by pluto; 03-14-10 at 02:50 PM.
03-14-10, 07:12 PM
#663
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03-14-10, 09:06 PM
#664
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Nice vid, but dahm.....can you please take your visor off? that was getting to me and I was only watching the vid lol. I can emagin how anoying that must have been while driving =P
03-14-10, 10:18 PM
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I guess you are talking about the helmet face shield keep dropping down? It was very annoying but I keep forgeting to tighten it up before the next session...
03-18-10, 08:09 AM
#667
I wonder why Tein Super Street for FD3S in US is different from the rest of the world?
From Tein USA
part number
SM50-KUSS2
Comes with 12kg/10kg taper spring
From Tein Japan & UK
part number :GSM32-B1SS3 with upper mount (Japan) , QSM32-BVSS3 with upper mount (UK)
Both comes with 8kg/7kg straight spring
Why the US version use taper style with high rated spring? Also I noticed the rear spring for US is much shorter in free length (200mm) compared to (225mm) for Japan/UK spec.
I recently bought Tein SS from japan with 8kg/7kg straight spring. Should I change the rear to 6kg?
From Tein USA
part number
SM50-KUSS2Comes with 12kg/10kg taper spring
From Tein Japan & UK
part number :GSM32-B1SS3 with upper mount (Japan) , QSM32-BVSS3 with upper mount (UK)
Both comes with 8kg/7kg straight spring
Why the US version use taper style with high rated spring? Also I noticed the rear spring for US is much shorter in free length (200mm) compared to (225mm) for Japan/UK spec.
I recently bought Tein SS from japan with 8kg/7kg straight spring. Should I change the rear to 6kg?
03-26-10, 05:39 AM
#668
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Saw noone responded. I can't answer why the different rates - but the free length is based on compressed length. Just take for example, ~750lbs static weight per corner. A 7kg spring will compress much more than a 10kg spring. Hence the longer free length.
03-31-10, 10:36 AM
#669
If you guys are interested, you can get the Tein SS UK version for a decent price. These coilovers come with the 8kg/7kg springs as stated above.
I did some searching and e-mailed a company in the UK to see how much total cost would be. This is what they said:
"Tein use different rates on US vehicle kits as there are differences in the road surfaces.
If you would prefer the kit from the UK, we can ship to you no problem. The total would be Ł800
We can take payment by bank wire or paypal with Ł20 fee"
According to google, Ł800 is $1,212. Not a bad price for brand new coilovers with a good spring rate huh?
The company that quoted me that price is WWW.SRBPOWER.COM
I did some searching and e-mailed a company in the UK to see how much total cost would be. This is what they said:
"Tein use different rates on US vehicle kits as there are differences in the road surfaces.
If you would prefer the kit from the UK, we can ship to you no problem. The total would be Ł800
We can take payment by bank wire or paypal with Ł20 fee"
According to google, Ł800 is $1,212. Not a bad price for brand new coilovers with a good spring rate huh?
The company that quoted me that price is WWW.SRBPOWER.COM
04-18-10, 08:22 AM
#673
Racing Rotary Since 1983
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the first 3 pictures show wear to the corner of the tire. the location and appearance of the wear indicates the tire is rubbing some part of the car.
too much camber is indicated on the tread face, not corner, of the tire and can be read across at least a third, if not more, of the tire.
howard
too much camber is indicated on the tread face, not corner, of the tire and can be read across at least a third, if not more, of the tire.
howard
04-30-10, 07:02 PM
#674
the first 3 pictures show wear to the corner of the tire. the location and appearance of the wear indicates the tire is rubbing some part of the car.
too much camber is indicated on the tread face, not corner, of the tire and can be read across at least a third, if not more, of the tire.
howard
too much camber is indicated on the tread face, not corner, of the tire and can be read across at least a third, if not more, of the tire.
howard
You were absolutely correct. I couldn't find anything in the rear that would cause the particular wear on the outside edge but when I looked up front, saw the tires had the weird "stripes" on both the outside and inside edge. As it turns out, the screws that bolts the liner to the outer edge of the fender were the culprit. Since my tires don't come anywhere near the edge unless I'm at the track, didn't really put 2+2 together.
Thanks.
Daniel
04-30-10, 09:07 PM
#675
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I'm now a participant in this thread
Hi, gang. I'm joining up on this thread, which I've read with interest ever since Howard started it.
I started out with AD coilovers and 550/450 springs. on 8.5/9.5 BBS RGR rims. Went from old Toyo T1S tires to BFG R-1s, 255/275, which was a big help. Still, like Howard aludes, the back end was happy, esp the lower the gas tank got. So I went and solved that with new goodies:
http://www.headonphotos.net/gallery/...zda/index.html
The new wing is obvious (JKLs GT-A **** replica), their rear diffuser is a bit more difficult to spot in the photos.
Back end now sticks. On a higher speed track like Thunderhill, it is wonderful.
New problem - the faster I go, the looser the front end gets. Gee, wonder why? Based on all of Howard's advice, I has a suspicioun that I'd lose grip in the front as I increased speed with the wing pushing down harder and harder. I'm still faster in turn 1 now, but it is unnerving to feel the front end not want to bite.
We're working on a splitter now. I also don't have a race seat yet, I hear good things about Kirkey's Intermediate Road Race seat, esp for the cost. I could sure use it, as I'm now fighting all sorts of new forces and the stock seat doesn't cut it anymore. This is on the list (funny how Howard just said I need one).
http://kirkeyracing.com/index.php?li...&code=Series47
I also have not corner balanced the car, I've just used the 'even height at the fenders' routine...however, now that I've gutted the car's interior, who knows what sort of weight distribution I have now. I will get the car corner balanced before my next event.
My father says he's discovered a new oxymoron - we call it Racing Budget. He's 63 and kicking tail in ST2 down in AZ, should go to Nationals this year. Hope to join him someday.
Beast
I started out with AD coilovers and 550/450 springs. on 8.5/9.5 BBS RGR rims. Went from old Toyo T1S tires to BFG R-1s, 255/275, which was a big help. Still, like Howard aludes, the back end was happy, esp the lower the gas tank got. So I went and solved that with new goodies:
http://www.headonphotos.net/gallery/...zda/index.html
The new wing is obvious (JKLs GT-A **** replica), their rear diffuser is a bit more difficult to spot in the photos.
Back end now sticks. On a higher speed track like Thunderhill, it is wonderful.
New problem - the faster I go, the looser the front end gets. Gee, wonder why? Based on all of Howard's advice, I has a suspicioun that I'd lose grip in the front as I increased speed with the wing pushing down harder and harder. I'm still faster in turn 1 now, but it is unnerving to feel the front end not want to bite.
We're working on a splitter now. I also don't have a race seat yet, I hear good things about Kirkey's Intermediate Road Race seat, esp for the cost. I could sure use it, as I'm now fighting all sorts of new forces and the stock seat doesn't cut it anymore. This is on the list (funny how Howard just said I need one).
http://kirkeyracing.com/index.php?li...&code=Series47
I also have not corner balanced the car, I've just used the 'even height at the fenders' routine...however, now that I've gutted the car's interior, who knows what sort of weight distribution I have now. I will get the car corner balanced before my next event.
My father says he's discovered a new oxymoron - we call it Racing Budget.
He's 63 and kicking tail in ST2 down in AZ, should go to Nationals this year. Hope to join him someday.Beast