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Posted by: kevgentile Jul 18 2005, 06:02 PM

anyone in the washington d.c./metro area have the sheridan 914 "narrow" kit installed on their car. i am looking for a high quality kit that fits well. bought some other fiberglass pieces and was very unhappy with it. if anyone nearby has it i would like to take a look at it. anyone else who has experience with it, your comments would be greatly appreciated as well. thanks

Posted by: Brad Roberts Jul 18 2005, 06:07 PM

I have dealt with it all. Rogers stuff is the BEST fitting available hands down. Hopefully you get to see this first hand. I have been buying Rogers stuff since 1995 or so. He knows me well. We just painted a narrow body nose this past weekend.

I'm not sure what you want to use the car for... but he will lay it up for street or race.


B

Posted by: SirAndy Jul 18 2005, 06:16 PM

http://www.ultimate914.com/

Posted by: kevgentile Jul 18 2005, 06:37 PM

the car is an open cock-pit track car. i didn't find out about sheridan till after my problems with the other fiberglass. i had completely removed the front fenders by drilling out the spot welds. but the fg fenders were so crappy that i had to reinstall the steel fenders. i like the look of sheridans kit, but my main concern is its method of attachment to the front. will i need remove the steel fenders again or trim them?
thanks for the replys.

Posted by: Headrage Jul 18 2005, 06:50 PM

Eeewww, nice stuff. Can any of it be used for the street?

Posted by: Brad Roberts Jul 18 2005, 07:05 PM

Rogers kit is designed to remove the fenders. Normally we leave 1.0-1.5 worth of steel for front attachment.


B

Posted by: redshift Jul 18 2005, 07:13 PM

Brad, in your opinion, could the fenders be cut, and molded into the stock body, so the the stock bumpers are used?


M

Posted by: Brad Roberts Jul 18 2005, 07:21 PM

Yes. I'm betting he would lay it up without the 75/76 front bumper in place.


B

Posted by: redshift Jul 18 2005, 07:30 PM

Thanks, as always dood!



Hmm... seems like a worthy option.


M

Posted by: Brad Roberts Jul 18 2005, 07:45 PM

It can be used on the street, but the splitter might get beat up. We install "plastic/UHF" on the bottom of all of ours. This gives the splitter more strength and the UHF takes the driveways/curbs instead of the fiberglass.

B

Posted by: kevgentile Jul 19 2005, 04:28 PM

anybody have any detailed pictures of their car to show how they attached the glass to the nose...where the fenders were cut.
thanks again

Posted by: SirAndy Jul 19 2005, 04:48 PM

scotts 3.0L with a sheridan nose ...


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Posted by: SirAndy Jul 19 2005, 04:48 PM

and off ... detailed enough?




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Posted by: SirAndy Jul 19 2005, 04:49 PM

rogers very own race car ...




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Posted by: SirAndy Jul 19 2005, 04:50 PM

and off ...




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Posted by: Brad Roberts Jul 19 2005, 04:56 PM

He has a tub car Andy.. that wont do much good..


B

Posted by: kevgentile Jul 19 2005, 05:41 PM

the photos are great and help out some, but does anyone have detailed photos of the "standard" body.
thanks for the help

Posted by: redshift Jul 19 2005, 07:12 PM

Yeah.. peeboy!




M

Posted by: pokey1168 Jul 19 2005, 07:57 PM

This is SOOOOOO off topic.......but mmmmmmm Brad I LOVE the your avatar car.....That is one SAWEEET ride.

Posted by: kevgentile Jul 22 2005, 07:39 PM

after comparing the two body style i have decided to go with the wider version, love the two-piece design. still hoping to find someone within driving distance of maryland that has the sheridan kit on their car.

Posted by: airsix Jul 22 2005, 09:26 PM

Boy, I bet that thing is a handful to steer with that kind of geometry. Red line through strut should hit the ground well inside the contact patch. Just an observation - not meant to offend.

-Ben M.


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Posted by: SirAndy Jul 22 2005, 09:37 PM

actually, it's surprisingly easy to steer that car ... not sure why ...

Andy

Posted by: Scott Carlberg Jul 23 2005, 01:04 AM

http://www.ultimate914.com/MOTORSPORTS_WE/STANDARD_BODYx.html

Posted by: Brett W Jul 23 2005, 01:32 AM

It is pretty easy to steer because of the large amount of caster, but the large scrub radius probably beats the hell out of the driver over the length of the session.

Posted by: J P Stein Jul 23 2005, 09:28 AM

Once you're underway, it's not too bad...mine has a similar problem. At low speed in a tight situation(like in the pits) it sux. The tires shuffle.....think understeer at 5 mph. Fortunately, parallel parking is not required
The wonders of Macpherson strut suspension.

Posted by: airsix Jul 23 2005, 02:53 PM

QUOTE (J P Stein @ Jul 23 2005, 07:28 AM)

Once you're underway, it's not too bad...mine has a similar problem. At low speed in a tight situation(like in the pits) it sux. The tires shuffle.....think understeer at 5 mph. Fortunately, parallel parking is not required The wonders of Macpherson strut suspension.

I wasn't thinking too much about steering effort - more about feedback from dips, bumps, pavement joints, etc. The farther outboard that tire is the more leverage it's got to yank the wheel around in your hands. (I'm having momentary recolection of the time I was fording a stream in a deux-n-a-half and hit a rock that spun the wheel so fast one of the spokes broke my thumb.)

-Ben M.

Posted by: bd1308 Jul 23 2005, 05:36 PM

i got a finger stuck in one of the decorative hole in the spoke of a grant steering wheel in my Jeep.....


LONG day

Posted by: Brett W Jul 23 2005, 09:09 PM

Ben is right. Large scrub radius can make a race car very hard on the driver. The feedback through the wheel will tire out a good driver.

Posted by: airsix Jul 24 2005, 09:42 AM

QUOTE (bd1308 @ Jul 23 2005, 03:36 PM)

i got a finger stuck in one of the decorative hole in the spoke of a grant steering wheel in my Jeep..... LONG day

NICE. Makes me feel I'm not so alone in this world. I thought I was the only one who gets into messes like that!

-Ben M.

Posted by: Brad Roberts Jul 26 2005, 01:42 PM

Correct. The bumpsteer is dead on (adjusted at the strut) The key is "track" It takes little to NO effort to make the car turn in. Feedback is no worse than anything else I have driven with 10inch wide radials and NO rubber in the steering system. Feels just like a go-kart.



B

Posted by: redshift Jul 26 2005, 01:48 PM

QUOTE (airsix @ Jul 24 2005, 11:42 AM)

QUOTE (bd1308 @ Jul 23 2005, 03:36 PM) i got a finger stuck in one of the decorative hole in the spoke of a grant steering wheel in my Jeep..... LONG day NICE. Makes me feel I'm not so alone in this world. I thought I was the only one who gets into messes like that! -Ben M.

You wish.

I used to have this girlfriend who wore cross-your-heart Chinese handcuffs.




M

Posted by: andys Jul 26 2005, 04:16 PM

QUOTE (Brett W @ Jul 22 2005, 11:32 PM)

It is pretty easy to steer because of the large amount of caster, but the large scrub radius probably beats the hell out of the driver over the length of the session.

Brett,

Large amounts of caster would make the car yet more difficult to turn and produce a lot of weight jacking. Caster is good for keeping the car stable in a straight line. Pehaps you meant *small* amount of caster?

The picture suggests there's a lot of scrub radius, which in itself is not necessarily a bad thing, but it accentuates steering effort/feedback and weight jacking when caster is increased. Can't tell from the pic, but it's possible that the KPI was reduced....which will reduce steering effort (generally). AFAIK. Thoughts?

Andy

Posted by: Brad Roberts Jul 26 2005, 04:38 PM

Caster is not adjustable on this car. It was set at -6deg. We played around for years from -5 to -6. When the chassis was on the jig the camber plates were welded at -6.

About the only time where I have seen caster make a difference is in AutoX. otherwise I personally set them all up between -5.5 to -6.0

B

Posted by: Brett W Jul 26 2005, 05:59 PM

Lots of "negative" caster will not make a car hard to steer. I ran 6 degrees on my street car and have designed as much as 10 degrees into some race cars. It is good for camber gain in a strut situation. This "jacking" effect that you refers to really only occurs at large steering angles such as those incurred in a street car. Race cars don't use anywhere near as much steering angle. The KPI can be used to offset this in a street car. Since the factory set the strut at a 10 degree angle running, the drawbacks of large amounts of caster are offset by the KPI.

A large scrub radius is bad thing anyway you look at it. Any bump of cornering force exerts a twisting force on the steering that is proportional to the scrub radius. Cars with zero scrub radius can be driven without power steering becasue these twisting froces are gone. But zero scrub radius cars can feel very numb. The driver needs a little feedback to "feel" what the tires are doing so havinga minuimal amount of scrub radius is useful. In my cars I shoot for a minimal amount of scrub radius. In most applications the large amount of KPI that the factory built into our cars helps decrease the large scub radius because the wheels can't be crammed over the struts.

Posted by: pokey1168 Jul 26 2005, 06:45 PM

OK, just so you guys know. I have been under and around cars my whole life. I deal with some technically advanced medical implants and procedures, but listening to you guys talk about the suspensions on these cars makes me feel like a monkey doing a math problem.

BTW I am dam# glad to know that there are people like this that I may have to call on later for the rust bucket.

Posted by: J P Stein Jul 26 2005, 08:08 PM

The feel is a good thing......if the car even starts to push, you feel it immediatly through the steering wheel. As for turn in....with front & rear toe out it turns in super but as the lock increases so does the effort....I notice myself grunting when I really crank some in......the good news is it will snap back *real* quick if you let the wheel slip back thru your hands to catch one of them tank slappers.
These are mostly autocross problems/set-ups. I'd hate to drive my car at high speed on a track with it's present set-up

Posted by: Brad Roberts Jul 26 2005, 08:13 PM

The knowledge available is unmatched here. Some of it is difficult to digest, 99% of it has to be experienced to understand. Unless you have raced or "worried" about scrub radius... none of it means much. The car pictured requires about 4 inches of "turning the wheel" to make it go were you want. It is not ideal, but SCCA allows for something like 52 inches of front track for GT2. The wider the track the easier the car turns in. The front track on this car is .500 wider than the rear. It is almost impossible to get this car to understeer (even in tight stuff).


B

Posted by: Brett W Jul 26 2005, 11:49 PM

Now you guys can see why I have such a fit when someone says "just crank the t-bars down to get the car lower" , "it'll handle better".

Brad is correct, when you widen the front track width you decrease the weight transfer, thus allowing to for better cornering as well as less diagonal wieght transfer. Most street cars come with either equal or smaller front track. My race car will have a track of 60 inches front and 58 rear. It should work great.

The only drawback to wider track is the increase in frontal area which can cause more aero drag. Many F1 cars have track widths of 54-58in where many dirt track cars have a track width of 80-88in. Rules really determine where that falls.

Posted by: pokey1168 Jul 27 2005, 04:09 PM

OK, after reading and trying to keep up, don't be too surprised when you see me on here begging for advice. I have the floorpans to worry about first, but rest assured the work will definitely get around to suspension set up. She won't be going back to original, so I may let her get closer to the road by a couple of inches if I can do it without losing to much in ride quality.

Posted by: J P Stein Jul 27 2005, 05:10 PM

An observation from the driver training thingy.

On a 75 foot radius skid pad every car there understeered...initialy at least......this included all the Porsches, a Beemer, even a Honda NXS or what ever the rear engined jobbie is called. With some coaxing, a few got the back end out. The new 997 (8?) "S" that wouldn't turn off his stability controll & plowed around all day....but not as bad as the Hemi Charger (?) 4WD station wagon that slew it's front tires.

Did I mention that R35 Hoosiers have a fair amount of grip?
I was cooking till I hit "the bump" & bounced my haid off the cage...even with bar padding & the helmet it knocked me crosseyed....that was enuff for me.

Posted by: SGB Jul 27 2005, 06:34 PM

Hey Brett!
Although I didn't just "just crank the t-bars down", I'm pretty sure I could use some serious front end realignment. It is as low as it will go without hitting the bump stops often, and has a pretty big bump steer kit that was in when I last had it 4-wheel aligned many years ago. I know you told me before that you do oyur own alignments. Could I convince you to help me get my front end -better? It doesn't have any problems and tracks straight, but I'll bet it isn't even close to ideal. Whattayasay? Got enough time? I'll bring the beer or coffee or whatever!

Posted by: Brett W Jul 27 2005, 07:48 PM

Next week I may have a little time.

Posted by: redshift Jul 27 2005, 08:51 PM

Does anyone have a Sheridan body I can get a mold from?




M

Posted by: Brett W Jul 27 2005, 11:44 PM

I have a car that could be used for a mold to make our own more aero body work than the Sheridan kit.

Posted by: andys Jul 28 2005, 10:10 AM

Brett,

I suppose we could go on for hours; it'd be fun, no doubt. So, just a couple of comments.

First, just to set the grounds for your opinion; by negative caster, I assume you mean that the tire contact patch (where the verticle centerline of the wheel meets the road surface) is trailing behind the king pin (or axis of the strut) as it intersects the road surface. Hmmm, is that confusing? How about: The king pin is rotated opposite the direction of tire rotation. I use "king pin" as it's easier to describe in few words, and is easier to visualize.

I know of no example where adding caster does not increase required steering input. Increaesd caster will always ceate an increase in weight jacking (and increased effort), and is especially accentuated when using wide tires. As such, it takes very little steering input to creat jacking in your wide tire example. That's what makes race setups so much more difficult that a narrow tire'd street application. I think we both realize that there's a balance between caster and KPI; some refer to it as a compromise, as one begets the other. There's no perfect solution.

A strut suspension usually dictates how little scrub radius you can run due to it's design (as opposed to say a double wishbone design). I agree that you can usually benefit from some scrub radius to provide the driver with some "feel." Some trends in suspensions have moved towards very little caster and KPI, and larger scrub radii, but the jury's still out, AFAIK. It does create a little more stability in the front end dynamic behavior at the cost of dartiness and straight line stability.

Thanks for the interesting discussion,

Andy