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1987 FC road race pushy!

Old 04-09-13, 08:11 AM
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1987 FC road race pushy!

Good day!

I finally got my 1987 FC on the track. it has some older tokiko Blues, stock springs, stock swaybars, Star Spec tires, Hawk black pads. The car has mostly stock bushings (old)

For alignment:

Front 1/8" toe out. 2.8 deg front camber
Rear 1/8" toe out. 1.5 deg rear camber

The car is REALLY pushy! I don't think I could spin the car if I tried!

I added some circle track spring rubber to the rear springs to stiffen them up a bit. This helped a good bit, but didn't solve it entirely.

I know most people take the rear sway off the car. This would make it push even more! How are you guys getting your cars to turn?

This is for a budget limited class. Anything I do needs to be cheap!

Thanks!

Rob R.
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Old 04-09-13, 08:25 AM
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Rear should be toe in.
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Old 04-09-13, 09:26 AM
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If I toed in the rear wouldn't that make it have even more rear grip? WE started with 1/8" in and it got better when we went out.
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Old 04-09-13, 10:26 AM
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I'm going to go out on a limb and say the stock springs and sway bars are a big part of the problem.
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Old 04-09-13, 10:29 AM
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Things i would try.

Spacers up front.

Use white shoe paint and paint outer edge of front.tires. if it doent.wear. you possibly have to much negative camber up front.

Try more air.pressure on rear tires only.

New bushig for.rear only.. ehehe
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Old 04-09-13, 10:40 AM
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The outer edges of the front tires are worn more that the rest. I was thinking I needed MORE front camber.

What do you mean by spacers up front?

What spring rate would you use on the rear? What swaybar on the rear?

Its gotta stay CHEAP!

Thanks!

Rob R.
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Old 04-09-13, 11:32 AM
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what pressures are you running? put more air pressure in the front tires, they're probably rolling over onto the sidewalls

you could probably do more front camber, I run -3.5*

are you running stock wheels/tire size?

anything you can do to stiffen the front end would help, be it either springs or a sway bar. (one of the reasons you're probably understeering is you're bottoming out the front suspension because it's so soft.)
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Old 04-09-13, 11:56 AM
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front is too soft, you would need like neg 5 deg of camber in the front and that may still not be enough for stock springs and bars. Stiffen up the front springs and bar...and lower the front end at the same time

what does the car weigh with driver?

Dont mess with the rear till you get the front stiffer...or you are just balancing the car by decreasing overall grip. It sounds counter intuitive but until you are using the full front contact patch the usual handling adjustments don't really apply that much.
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Old 04-09-13, 12:10 PM
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Originally Posted by wvumtnbkr View Post
The outer edges of the front tires are worn more that the rest. I was thinking I needed MORE front camber.

Rob R.
yep, start there.
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Old 04-09-13, 12:11 PM
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The car weighs about 2450# with driver.

Tire pressures are 38 hot front 37 hot rear on 205 50 15 star specs. Stock wheels.

Any cheap easy ways to increase the front stiffness?
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Old 04-09-13, 12:12 PM
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Originally Posted by Travis R View Post
I'm going to go out on a limb and say the stock springs and sway bars are a big part of the problem.
This. Dollars to donuts the camber and grippy tires are allowing enough side loading to make the front suspension corner on the bump stop, a recipe for understeer if there ever was one.
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Old 04-09-13, 12:41 PM
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Originally Posted by wvumtnbkr View Post
The car weighs about 2450# with driver.

Tire pressures are 38 hot front 37 hot rear on 205 50 15 star specs. Stock wheels.

Any cheap easy ways to increase the front stiffness?
how cheap are we talking? you could probably get used coilover springs and collars pretty cheap.

I'm running these sleeves on the front of my car:
http://www.amazon.com/gp/product/B006K8TCJ6/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1 http://www.amazon.com/gp/product/B006K8TCJ6/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
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Old 04-26-13, 07:47 AM
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Here is my game plan for now....

I am going to run 200# front springs on adjustable collars. I am going to take 1/2 a coil out of the rear and add a spring rubber (My math says this should make the rear spring rate about 125 #).

I am adding front end camber for a total of 3.5* per side.

I plan to drill a new hole in the sway bars (front and rear) about 1" away from the current mounting hole (making the moment arm shorter).

Any other cheap / free suggestions? Anybody have any reasons why this wouldn't work?

Thanks,

Rob R.
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Old 04-26-13, 01:20 PM
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I'd run stiffer than 200#.... I have 600 lbs/in on my car. Most track guys run ~400 lbs/in in the front.
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Old 04-29-13, 12:22 PM
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for a roughly 2400-2600lb car (includes driver) you want to be at around 400lbs springs with a pretty good size sway bar. With this you can run right around 3 deg negative and achive a pretty good front wear and even tire use.
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Old 05-02-13, 03:40 PM
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Originally Posted by eage8 View Post
I'd run stiffer than 200#.... I have 600 lbs/in on my car. Most track guys run ~400 lbs/in in the front.
400# Springs??

Is this not WAY too much? I am having snap loose issues in my FB and I am trying to learn as much as possible about the front skipping/chattering going on in our car. We run 125# springs, but the highest I have heard people running is a bit over 200#s. Does anyone else have some knowledge they can share about spring rates/suspension set ups in an FB?

Thanks guys!

Also, wvumtnbkr, do you have any photos of the car in the corner? We learned a ton about how out of whack our setup was from photos. It sounds dumb, but you tell whether you are pulling the inner front tire off the ground etc.
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Old 05-02-13, 05:28 PM
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Originally Posted by zoom63 View Post
400# Springs??

Is this not WAY too much? I am having snap loose issues in my FB and I am trying to learn as much as possible about the front skipping/chattering going on in our car. We run 125# springs, but the highest I have heard people running is a bit over 200#s. Does anyone else have some knowledge they can share about spring rates/suspension set ups in an FB?

Thanks guys!

Also, wvumtnbkr, do you have any photos of the car in the corner? We learned a ton about how out of whack our setup was from photos. It sounds dumb, but you tell whether you are pulling the inner front tire off the ground etc.
the old pro7 spring setup was 350/175... not saying its the perfect spring setup for an FB or anything, but its pretty normal.

FC's are typically 300-450 in the front...
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Old 05-03-13, 08:49 AM
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Originally Posted by j9fd3s View Post
the old pro7 spring setup was 350/175... not saying its the perfect spring setup for an FB or anything, but its pretty normal.

FC's are typically 300-450 in the front...
I appreciate the info man. I am very much a rookie with finding good spring/suspension setups. We are finally to the point where we can work on these things, rather than worrying about power etc.
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Old 05-29-13, 06:44 AM
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the fc is very pushy from the factory and even modified unless drift knuckles and other tricks are implemented. i didnt read the whole thread because its late...but pm me for handling and suspension advice. i can help you..
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Old 05-29-13, 10:52 PM
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you dont need knuckles or other exotic geometry horseshit to make an FC handle well. Just needs a lot of spring. I'm at 700/500, with an ST front bar on stiff, no rear bar, staggered tires, and its a little loose.
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Old 06-01-13, 01:12 PM
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<*sigh*>
So much misinformation, so little time.

Do a search through this forum - FC suspension has been discussed many times. Here is the condensed version.

400# springs front, 225# rear, Racing Beat front sway bar, no rear bar. Shocks/struts were usually something like a koni yellow. A KYB-AGX was about the minimum needed given the front springs. Car is lowered. Camber adjustment plates front, adjustable center link in rear. You should be able to set at least 2.5* neg camber in front an a little less in the rear. Rear steer bushing setup should be eliminated.

This is kind of a "base" setup for an SCCA ITS-level car (around 2680# w/ driver, about 170rwhp). 225/45r15 tires on 15x7 rims. You need the front stiff to prevent roll (and associated camber loss) and the rear soft to let you put down power.

With the above set up, my car is fairly neutral. Over/under steer can be adjusted for with shock settings and tire pressures. A couple psi change front-to-rear can make all the difference.

Good luck,

-b
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Old 07-01-13, 04:38 PM
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Originally Posted by wrankin View Post
<*sigh*>
So much misinformation, so little time.

Do a search through this forum - FC suspension has been discussed many times. Here is the condensed version.

400# springs front, 225# rear, Racing Beat front sway bar, no rear bar. Shocks/struts were usually something like a koni yellow. A KYB-AGX was about the minimum needed given the front springs. Car is lowered. Camber adjustment plates front, adjustable center link in rear. You should be able to set at least 2.5* neg camber in front an a little less in the rear. Rear steer bushing setup should be eliminated.

This is kind of a "base" setup for an SCCA ITS-level car (around 2680# w/ driver, about 170rwhp). 225/45r15 tires on 15x7 rims. You need the front stiff to prevent roll (and associated camber loss) and the rear soft to let you put down power.

With the above set up, my car is fairly neutral. Over/under steer can be adjusted for with shock settings and tire pressures. A couple psi change front-to-rear can make all the difference.

Good luck,

-b
Good info in this post. Suppose you're trying to improve a Lemons car and can't spend that much money (or look like you've spent that much money). Are there any lowering springs available that come close to the suggested spring rates? Or do you pretty much have to go to a perch/sleeve set up so you can choose your spring rates? It looks like all the springs out there are somewhere around 150 lb fronts - pretty far off from the suggested 350-400 lbs suggestions. Is there a cheap way to put linear springs on the front of these cars, maybe with some slight modification to the perches? And how much negative camber is possible without getting camber plates?
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Old 07-01-13, 05:02 PM
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comparing spring rates between different cars (or between different generations of cars in this case) is an apples and oranges exercise.

do some interwebs reading on motion ratio and subsiquent effective wheel rate...

The right spring rate for a given weight on an FC will not be the same for an FD nor will it be right for 1st gen...

Further anyone pushing spring rates as ideal without any real consideration of the weight of the car should be ignored.
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Old 07-01-13, 05:35 PM
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Originally Posted by RockLobster View Post
comparing spring rates between different cars (or between different generations of cars in this case) is an apples and oranges exercise.

do some interwebs reading on motion ratio and subsiquent effective wheel rate...

The right spring rate for a given weight on an FC will not be the same for an FD nor will it be right for 1st gen...

Further anyone pushing spring rates as ideal without any real consideration of the weight of the car should be ignored.
Nevermind... I had typed up a reply but realized you were just making a general reply to the thread, not my question a couple replies up.
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Old 07-01-13, 05:52 PM
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I just read elsewhere in the forums that Racing Beat springs are linear. On RB's site, they specifically mention that the FD springs are linear but do not mention the springs for the FC application being linear. I sent them a note to find out for sure. Though ideally we'd choose our spring rates based on the weight of the car, it's a Lemons car, so it's got to be done on the cheap.
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