Hey did you guys hear about the kyoto threads?

[RedLS1GTO]

Originally Posted by island14

It's kinda hard to read all this with you telling the story just in type here without seeing the car in action.. and knowing more of all changes that have been done to the car..

If I felt it myself while driving the car, I may even describe the problem a bit differently than you do..

You mean you can't diagnose a handling issue over the internet with a couple of pictures?? Come on man...

I'll be honest, it doesn't feel like anything. I like to think I have a pretty well calibrated butt, and I don't notice it at all when it happens. It feels smooth and stable. If I wasn't sucking tire smoke into my helmet blower every lap and shredding the right front, I probably wouldn't have even realized it was happening. It took seeing pictures that others had taken and listening to what the guy in the other car was seeing before I was able to piece it together.

Originally Posted by island14

And myself I would work with the bar first also If I were you, after all it's just another spring making everything stiffer..

Definitely the easiest. If taking bar out of it makes it go away or even makes it worse I'll at least have a good reference point.

Originally Posted by island14

Have not considered you may be running out of shock travel... or binding.. is it possible?

Definitely not that. There is plenty of shock travel left at that height. At least another 2-3". When you jack the car up, it's the sway bar that stops the front travel, not the shock. There isn't anything I see that could be binding. As you know, these things really aren't that complicated, but with a gazillion points of adjustment, it's a lot easier to screw it up than get it right.


I know you know a lot of people in the area. You don't know anybody with a good chassis setup do you? I'm mostly limited to what I can do in the garage. I'd love to get the thing up on a good rack and really zero in what's happening.

[island14]

When you jack the car up, it's the sway bar that stops the front travel,

How much travel down does it have before it runs out? could it be just this simple?

I don't know anyone with a good chassis set ups for what you do.. but for the local oval tracks yes..

He also asked if possible the brake was dragging or not returning all the way, suggested a spring on it... but you say no...

I'm talking to him now in facebook, hes slow to reply with his cell phone and probably at work..

I'm working on your issue with him, but also want to hear what he thinks for springs and set up just out of curiosity myself...

I see from watching the video you posted a lot of braking going on, so lots of weight gets transferred to the front.. and maybe why Howe's guys told you so stiff on the springs.. we are more worried about bottoming out, not nose dive from braking..

Also sent him the video to see the track better to make a decision..

Were talking about it now...

They use a lot of brakes at the end of the chute. do you think it can be softer with higher frame heights? what would be your plan if it was you and me going there?

Ill get back to you after we talk more..


Denny is good at this stuff, and he did it for many years as a full time job, not sure why he quit.. I did ask awhile back about your body, but did not seem interested in doing it and said it would end up costing him for taking off from his work, so left it alone for now.. got to catch him on a good day..

He gets cranky at times...

[island14]

Here is what we came up with after talking about everything you told me, if everything else we talked about is eliminated, its back to the bar, and that does need to let the shock extend, if not find a way to fix it..

As far as springs go, he thinks after you get the bar fixed you may be ok there.

He would also like softer springs, but with that hard braking corner its probably not going to allow it, so screws you over for the rest of the track..

Any changes or other calls would have to be made at the track, and even if he would go there with you (He won't, I asked) he would have to go around to some of the corners and stand there to watch the car to make any judgement calls on what to do.

Unlike an Oval track where you can just get up in the tower and see the car all the way around the track.

[island14]

One more thing, are the brakes air ducted? possibly getting hot and sticking?

Usually anything like this I mention you have already covered..


Also, is this the only track you race at? has it done it anywhere else?

At other tracks you may be able to use softer springs...

[island14]

Originally Posted by Drew M

thats where i would start

At first I was surprised to hear how they like a big bar and these heavy springs, now I see why after seeing the track, and talking about it with my old crew chief.. they don't have much choice...

I'm beginning to think maybe even that bar might be ok, but its just hanging up the suspension on that side under nose dive, and would probably do the same on a hard left turn if the track had one like that.

[Kneel 8250]

If you look closely at both the posted pics of your car, you have more body roll at the rear than the front and you are lifting the inside front but not the inside rear. That means the chassis is twisting. For me, I would stiffen up the rear bar first and take some of that chassis twist out. Then look at stiffer rear springs and if you are still dragging the front, go stiffer front springs. I would NOT soften the front bar except as a last resort, and if you do soften the front then raise the ride height a fraction at the front.

With the nut behind the wheel, you want to go faster, not slow down so ease the brake pressure a fraction before the brake locks. Driving fast is not easy so subtle changes in technique can sometimes make a big difference.

Best of luck.

Kneel.

[island14]

He mentioned the rear bar was un-hooked in an early post, I have never used one myself, but have been wondering if hooking it up might help myself..

Am still waiting to hear how much travel is stopped/lost from bar at the front, and possibly its just making the right side lift..

The first photo is deceiving to me, from the angle it actually looks like a corner exit, not entry, but guessing its just the angle it was taken and crops out the whole view.

[island14]

The more I think about it Kneel here may be on to something with that rear bar... have you tried it with it?

Also how much ballast do you have in that thing? any way to move some of it back for more rear weight?

[RedLS1GTO]

Originally Posted by island14

One more thing, are the brakes air ducted? possibly getting hot and sticking?

As of right now I don't think that it is anything brake related. On the day that the pictures were taken it was cold and I actually had trouble getting enough heat into them. They definitely weren't TOO hot. I've never seen anything but perfect performance out of the brakes.

Originally Posted by Kneel 8250

If you look closely at both the posted pics of your car, you have more body roll at the rear than the front and you are lifting the inside front but not the inside rear. That means the chassis is twisting. For me, I would stiffen up the rear bar first and take some of that chassis twist out. Then look at stiffer rear springs and if you are still dragging the front, go stiffer front springs. I would NOT soften the front bar except as a last resort, and if you do soften the front then raise the ride height a fraction at the front.

With the nut behind the wheel, you want to go faster, not slow down so ease the brake pressure a fraction before the brake locks. Driving fast is not easy so subtle changes in technique can sometimes make a big difference.

Best of luck.

Kneel.

The car definitely has more rear travel than front and is twisting. I've thought of hooking the rear bar back up. I had it hooked once and the car went full snappy oversteer on exit. I've made a few other changes since then so it may be worth a shot. Even trying it with some negative preload so it only started doing something after it rolled over a decent amount might be an option.

As far as the nut behind the wheel goes, it really may be as simple as coming off of the brakes a fraction sooner.

It was asked earlier if it happens at other tracks. The only other place I have seen it happen is the 2ns apex of Oak Tree at VIR... you guessed it, a slow right hander with deep braking and a late apex. At VIR it happens on occasion, not every lap like I was seeing at Road Atlanta. I didn't see anything of the sort at NCM.

Also, as far as ballast goes, I have everything as far back and to the right as it can go.

[RedLS1GTO]

Well fellas... I may have found something.

I was just laying under the thing seeing if anything stuck out and I noticed that the front sway bar is about 1.5" above the A-arms which means that the sway bar arms are at a bit of a down angle. As a bonus, it's juuuuuust slightly out of square with the chassis. The way it is angled would basically be a variable rate spring rather than linear. It also changes the effective length of the sway bar arms. I haven't measured it exactly to get real numbers but it would make it act as an even larger bar.

Since the calculation for the effective spring rate of the bar has arm length^2 in the denominator, that is a BIG influence.

Man, I need to get to a track!!!!!

[RedLS1GTO]

As for why it might be slightly out of square...

Remember this?



Notice that you can see the sway bar mount bent pretty badly:





I think that in making sure everything else was square, I perhaps overlooked the sway bar a bit and got it just a little out of whack.

[RedLS1GTO]

And by the way... I recommend this book to anybody who races. It has helped me more than I can even quantify. It is of course written for stock cars but there are a lot of things in here that would have helped in any of the previous cars.

http://www.amazon.com/Paved-Track-Stock-Technology-S239/dp/0936834374
I can't remember who recommended it to me... was it you Tim?

[Kneel 8250]

What you are chasing is balance side to side and front to rear. To disconnect a sway bar is a big change. If you have a lighter rear bar put that in and connect it up. The snap oversteer is the rear is too tight and not gripping up properly. When things get closer to being perfect to you make smaller changes. The balance front to rear is off. Don't be afraid to play around so you understand what changes you are making and what it does to the car.
Tire pressures you will need to play with also and each tire pressure could be a different pressure dependant on the road course you are running on.

Don't you just love the challenge of getting it all correct? I REALLY miss the racing but age and too many injuries have taken their toll.

Enjoy it all.

Kneel.

[island14]

Just curious..

Noticed the heim from your rack is bolted direct to the steering arm on the spindle and don't see any shims.

Do you have the bump steer set?

[island14]

Originally Posted by RedLS1GTO

And by the way... I recommend this book to anybody who races. It has helped me more than I can even quantify. It is of course written for stock cars but there are a lot of things in here that would have helped in any of the previous cars.

Paved Track Stock Car Technology (S239): Steve Smith: 9780936834375: Amazon.com: Books

I can't remember who recommended it to me... was it you Tim?

Wasn't me.. the pages I sent you are from the Duke Southards book

[island14]

Originally Posted by Kneel 8250

I REALLY miss the racing but age and too many injuries have taken their toll.

I miss it sometimes when I get to thinking about it, had some great times...

For me it got to be like an addiction.. that kept costing more and more till I went broke.

My shop was no longer making any money and the sponsors ran out.

Was no fun driving other peoples turd rides that can't win and just make you look bad, so ended up just selling out what parts I had left over.

Actually the guy I was talking about earlier in this thread is building a dirt modified this winter for next season and told me I can drive it if I want..

I know if he builds it that it will be a good car, and would love too! but have too many responsibilities here with my kids, and there wont be any money in it..

[island14]

Originally Posted by Drew M

So...I couldn't find my setup notes. Gosh that grinds my gears. I sat through hours of seminars for those and my attention span isn't much more than 5 minutes Ughhhh!

I'm really not that good of a chassis man myself, but have been around it a lot and know most of the basics.

I always made sure to have good guys that did know around as my crew chief though... and was good at explaining to them exactly what the car is doing and where.. so they can sort it out..

One thing I did notice though, is good drivers that are also good chassis men, are usually exceptionally good.

They usually know exactly what to do to their car, or try.. when they come in.. and can do it themselves or tell someone else to do it.

[RedLS1GTO]

Originally Posted by island14

One thing I did notice though, is good drivers that are also good chassis men, are usually exceptionally good.

It's funny you say that. I can see another car and know exactly what it needs even when the stubborn ass drivers, you know who you are, won't listen. It pains me to say that I might actually like tuning and wrenching as much as I like driving (and I'm probably better at it). I love the engineering, physics, and math behind it. Yea, I'm a nerd by degree as well as a nerd in life.

I have my own close, very close, but it bothers me that I know it could be better still.

[island14]

Originally Posted by RedLS1GTO

It's funny you say that. I can see another car and know exactly what it needs even when the stubborn ass drivers, you know who you are, won't listen. It pains me to say that I might actually like tuning and wrenching as much as I like driving (and I'm probably better at it). I love the engineering, physics, and math behind it. Yea, I'm a nerd by degree as well as a nerd in life.

I have my own close, very close, but it bothers me that I know it could be better still.

I know quite a few guys that are excellent chassis men, but can't drive, nor do they even bother to try.

Dirt is one that would love to drive, but no one will let him and he can't afford to fix the crashes..

He ain't skeered though, I heard hes pretty fast for about a lap or so before he hits a wall or something..



A good example really would be Childress, the guy wasn't a bad driver.. but he finally realized he was much better at building them than he was at driving..

And the rest was history..

[RedLS1GTO]

Wait... are you saying I can't drive??

Originally Posted by island14

Just curious..

Noticed the heim from your rack is bolted direct to the steering arm on the spindle and don't see any shims.

Do you have the bump steer set?

I skipped right past this one. That was all just bolted together to get it out of the trailer.

We drug it in the trailer with the winch and couldn't get the damn thing out until I had enough parts on it to make it at least roll.

I have the bump steer as close to 0 as I can get it now.