Hey Hardscrabble and 71 Fan

M

Mongo

Guest
Thought you could hide? LOL Hey guys, glad to be here. Ready for a sway bar question?
 
Thanks. It is a hot one here today. Hey Lumpy. Seems to be some old names here.
 
Dem..........didn't even know I was lost. LOL

Meet Mongo folks, an ex racer who still races at 1/10th scale. A self proclaimed knuckle dragger, you'll find he's a lot smarter than he lets on. And from what I can gather a right dem good wheel jockey.

71 is the aero (oreo) consultant for his efforts and they do a good job. Meanwhile I try to keep the chassis screwed up so they don't get ****y......

Sway bars?? ....BIG un's is usually the correct answer...........LOL
 
Where are you guys coming from?? What do you think of Todd Bodine and Larry Foyt?? :p
 
Usually coming from left field.........LOL

Todd Bodine is a dem talented driver. Maybe has as much talent as anyone in Winston Cup right now. But he is not a consistent driver and is not in the best ride out there. So what ends up happening is he tries too hard, with the end result being what is usually the end result when you push too hard, you wreck. And like all the Bodine's he's too dem stubborn to ever change.

Larry Foyt is just too inexperienced to be at the WC level yet. And his equipment is bluntly not WC standards either. So basically we have not seen him in a competitive situation that allow any clue as to what he has for talent.
 
Lumpy.....howdy.

Pull up a thumb and a keyboard and have fun..........always glad to see folks hanging out here.
 
Thanks, guys. Think I'll poke around a bit. Man, I squished Bobby in my avatar. Looks painful. :(
 
Usually coming from left field.........LOL


You guys are NOT going to stick me out in right again are you? :D

Mongo.....glad you made it. Understand yer having push problems at high speed again which tells me yer losing balance, or you are simply overdriving the car. Changing the steering gear might help. Re-cambering the front end might help. Could be a simple alignment problem.

Is there any possibillity that you have twisted the frame somehow?

Is this with or without the interior ductwork? If the duct is installed there is a good possibliity that it is

1. Slanted in such a way as to lift the front of the car.
or
2. Putting so much pressure on the spoiler that it is squashing the back down which in effect lifts the front.

If the duct is NOT installed, after checking the wheel and frame alignment, (do it the old fashioned way....sticks and a clamp.....you DO remember the old fashioned way don't you?)........go back to your notes and reset everything to the set-up you had when you came close to setting that track record, loosen it just a tad and then as I've heard somebody say....sit down, shut up, and drive. :D

Not sure what you want the set-up jig you are tying to design do, so can't really help there. Are you talking like an alignment jig down at the local garage or what because if that's all you want, slotted unobtainium bars with nuts and bolts instead of sticks and a clamp would work just fine.

God I hate playing right field.

Good to see ya buddy :bounce:
 
I'm just a tad lost here............my fault.

I am gonna assume you're pushing from the center out. Seems to be the most common problem. But I am not sure which track you're working with. Flat long, high banked long and it makes big difference.

Did ya ever fool with the no spring split or reverse spring split setups?? And what kind of spring split do you have now?

Is the front of the car bottoming at all in the center or entry to the corner?

Is the car porpoising at all?

First instinct is to lower the LF spring rate and up the LR spring rate. If the car is porpoising at the nose or bouncing at all, increase the front shock stiffness just a tad.

If this helps (these are big changes) you are on the right track.

If it does not help go back to the spring/shock combo you have and change the camber settings on the front. Move the RF one or two degrees postive and the LF one or two degrees negative.

If this helps, then we can go from there.

You can also try to diamond the corner just a bit. Let the car move up the track a hair at the center and then angle down just before you nail the throttle. SHould help get the car turned at a better exit approach and take some pressure off the front.
 
Yes I am a Ward fan. Isn't everyone? My Wife actually is a huge fan of Wards. We have Ward everything in this house and she has more #22 diecasts then I do of Dale Earnhardt Sr. ! LOL


Okay guys, here's the deal. Car still turns in great and you called it right. A push starts at the apex. As long as I stay off the gas it turns fine but the minute I get on it, it pushs out real bad. I have to back peddle it to keep it off the wall. Mark, if I do not back peddle it it WILL go into the wall.

Now maybe there is nothing wrong with it and maybe I am just getting to eager.

The question about the sway bars is this. I had the shocks off to check oil etc. and noticed when I lift one rear wheel the bar raises the opposite wheel also. So I sat the car down and "rolled" the chassis to watch the wheels and it would lift the inside the wheel. This does not seem right.

I do not think the chassis is bent because I have not been in any hard wrecks. I raced against some guys I had never seen before and they were cleaning my clock in the apex. I tried to look at their cars but could not see anything with their cars that was different then mine. Some where 4 wheel drive and some where rear wwheel drive.
They were running stiffer front springs then me so I changed but I did not see much difference. I have some really stiff front springs on order. I mean really stiff and will try them in the right front.

I have not finished the ducting. Just have not had the time because once I started feeling better I took Susan to S.F. and then we spent a few days in the Sequoias.

At the big road course track in Sun Valley they are having the 1/5th scale World championships. 1/5th is about the size of a Kart. I would rather have a kKart but anyways, we are going down to watch them. The eliminations and main is on Saturday. I am curious as to what they are using for an engine.
 
Are you running a front bar or only a rear?

Disconnect the rear bar, the car will usually turn better.

Go to smaller front bar and it will loosen the car up. A bigger front bar will tighten it up.

What type bars are they? Standard one piece or three piece torsion type bars?

You may have too much preload on the bars. Too much preload increases the amount by which the bars will effectively stiffen the springs.
 
No front sway bar. The rear is a standard one piece. I will see about the pre-load.

First I am gonna test it without the rear sway bar all together. Will let ya know.
 
Ok then, nothing has changed alone oreo lines and figuring the frame is still straight and the alignment is good.

Bottom line is that we must have more front weight/downforce and you've ALWAYS (or nearly) had trouble with push center off. I don't think I've ever heard you say the car was too loose with the large spoiler on it.

I think what's happening with the window holes not being lined up is that the air is rushing at the back window and not finding a clear way out. It's getting all mixed up inside the cabin. I think as it deflects off the rear window yer lifting the left rear which is putting extra weight on the right front which in turn is lifting the left front. Add this to the general front lift from stomping the gas and the front end breaks completely. Under braking this subtle bit of oreo is just not noticed.

Add a single piece of 1/2 in tape across the top of the front hole. Add another piece of tape vertically on the drivers side. This will at least decrease the pressure on the rear window. By having a larger rear than front hole we will decrease the cabin pressure and the amount of deflection. The taping in this manner will also add more downforce to the front keft of the car which seems to me where we are losing the battle.

Be sure to check head temp after a few laps....and then a few more laps......No sense in burning it up.

It also sounds to me like that rear sway bar is also helping to unbalance the car. Hopefully the disconnect helped.

Not sure if stiffer springs are the answer except that they would make the whole turn more consistant as there would not be as much front load on entry. I'm guessing you are still catching them going in.
 
I like the idea of taping of a portion of the hole. Good idea. Your right, I have always had a problem with a puch in the apex.. I removed the sway bar yesterday. The car was little more loose going in but still drivable so I have left it off.

I am wondering about the spoiler size. My line of thinking is that it may be helping to cause the push with too much downforce on the rear. But my concern is that if I go to a smaller spoiler the car will be squirrly in the straights.

Still hunting I huess for perfect balance I guess.
 
I gotta do some serious pondering here.

The car should have pushed like a bandit with the rear bar gone. But this twice now that doing the "wrong" thing for a push has worked the opposite way.

Gotta think about what difference, if any, AWD makes. The same with a fully independent rear suspension. Somehting is hanging around the back of my mind, and I can't seem to get it up front where I might just recognize it.

Basics..........On a scale of one to ten with ten being the stiffest available, what springs are running in the front. And what springs are you running in the rear. Just give me the colors if ya want, I think I saw a chart somewhere on them.

Very important to check the static weights again. Each wheel. How much weight (in any scale) is on each wheel?

Ride height, front vs rear and left vs right. Probably in mm if ya can.

Just a feeling some little factor is gumming the works here.
 
Blue's in the front. Red in the rear.

Spring ratings.

Green. 12 lbs.
Silver. 14.5lbs.
Blue. 17lbs.
Gold. 19.5
Red. 22lbs.
Copper. 25.lbs
Purple. 30lbs.
Yellow. 35lbs
White. 40lbs.

The springs I have right now are Red, Blue, Silver and Copper.

I am thinking maybe going really stiff in the rear, like maybe Yellow to get the chassis to force weight forward. What do you think?

As to all wheel drive. The manual says if you have the front diff loser, then you get more steering. The tighter the diff is, the less steering you get..

Rear diff, the tighter the diff is the more steering you get. Which makes no sense because like a spool or a locked diff, with no diff action in the rear you get more push/plowing.

Remember when I first got this thing we were fooling around and discovered loosening the front diff gave more steering?
 
Yep, I remember.

The tighter the rear diff the more likely to "slip" the rear around. Makes sense. Is there any way to measure front vs rear diff tightness? If they are near equal, I would definitely try loosening the front a bit.

Put a silver spring in the left front and a copper in the right rear. That should loosen the car up a bit as well. If ya get too loose going in, hook the sway bar back up.

Check your ride heights, if the front is higher or equal to the height in the rear, either drop the front .5 mm or raise the rear the same.

Betcha ya get somewhere with these.
 
I will try your set-up tomorrow. Going racing Friday night. The way the diffs are adjusted is like this. You tighten a screw in the center of the diff. This collapses a spring that keeps preasure on the diff rings. These diffs use 12 small carbide balls which act as spider gears. The 2 end plates ride against the balls. The spring tension holds the plates . You back out the screw to adjust the stiffness of the diff.
 
Wowzer HS......you are really going to raise that right rear and lower the left front with that spring combo. Makes sense....as I said, I think the prob is with sticking the left front when the car rolls over.

We also had good success when we did the Zippy Offset to the right rear which in effect changed the air deflection angle on the left front.

And yup, get that front valance to drag the track. Will anybody notice if we trim the valance on an angle say an eighth inch on the drivers side so we can tilt the body that way? (We could add more diagonal offset which would give us a better air deflection on the left front)

What about softer rubber up front?
 
71, I think we can get away with trimming the valance. The big things they look at in inspection is the body number, the rear and the size of the wing. As to softer rubber, there is a softer foam available(different shoar rating) but They wear down really fast. I mean really fast.

The more I am thinking about, I wonder if we shouldn't loosen the rear diff more. I guess I keep thinking about when I raced the big car and how much we always fought being tight until we finally got the bucks to buy a locker instead of having to run a spool.

Lowering the left front makes sense. I think you have been preaching this one for a long time. Doing this should not affect the way the body fits the template.

Kicking around maybe getting the Monte Carlo high down force body. What bothers me is doesn't high downforce also mean a lot of drag?
 
Downforce does increase drag but if the designers did their work right the drag coefficient is not increased dramatically.

It was HS who first said way back that there was an inequality in right/left bite. That you were relying too heavily on the right front to do all of the turning. The bite needed to be equalized better was what he (not I) was saying. I've just picked up that thought about how to get more downforce to the left front to help.

I'm thinking trim the left front and add another washer or two to the right rear post. You've always had plenty of top end and a higher spoiler might effect that but if ya don't get off the corner you ain't got a chance to get to the top end anyways. Gots to have that right rear stick and gots to have both fronts turning the car.

Have you ever checked tire temps? I think tho I don't know that once the fronts are close to the same we are closer to the goal. Scrabble might be able to fill us in on that.

The idea that the spoiler is lifting the front end is spot on but I think it has more to do with the added horsepower. I think yer poppin wheelies dude :D

Remember dude, we were beating the makes cars with the smaller engine. Unless you snuck something in without telling us, the only change has been more horsepower. You've either got to learn to be easier on the throttle coming off or we have to find a way to keep both fronts on the track. OR it's simply a front/rear differential problem that has been accentuated due to more horsepower. Probably best to not be too radical as it may just be a case of slowing down to go fast, or sit down shut up and drive :D

For the moment, go with added washer(s) on the right rear post, springs per HS, no sway bar, and tape on the hole. If ya still ain't got front bite and the head temp is ok, add more tape vertically, but if yer too loose to drive in hook the rear sway back up.

Also play with the differential tension because if ya are popping wheelies and the front wheels are turning too many rpms the thing will never ever stick up front.

Speaking of the right rear post washers. How many were on the thing that night you won? Whatever it was, go with that same amount.
 
Probably best to leave the rear diff stiffer, until the car goes loose you are putting all that power to the ground at that end. A good thing.

The springs in the front may be too soft, but it seems that if this were a problem the car would push a bunch on entry when the front really loads up.

Tire temps would be wonderful, nothing tells the story on what the four corners of the car are doing like tire temps. And even better would be two or three readings across each tire. Failing that, you can get a reading from tire wear if it is visible or measurable. Whichever tire is wearing the most is working too hard and whichever is wearing the least is just along for hell of it. You can learn even more if one or more of the tires is wearing unevenly across. Then ya got camber adjustments needed.

One other thing which might loosen the car up just a bit if it close to right would be to increase the Ackerman. I know it is adjustable on this car, but don't know by how much.

One more thing bouncing through my head. Do you have a way to check for bump steer? Wondering if going in you're gaining turn with increased bump steer as the front dives and then losing that steer as the nose comes back up on acceleration.
 
Okay Mark, hear ya on the coefficient. Smacked myself up side the head on this one. Yes I have been relying to much on the right front. My logic, which is messed up and I should be locked for, LOL says the left front is the "pivot point" and that is what should be turning the car.

That is also one of the deals that bothers me about Ackerman steering. The difference in the tire angle in a turn. To look at the angle of the tires, the left front is not turned as much as the right front. To me, it seems both should be the same angle and maybe the right front turned more.

With the transponder in the car my lap times are very consistant and right up there with the factory guys. I just feel we can improve on that. One thing I noticed was they are running a carbon fiber radio tray. It weighs the less then the cast carbon plastic tray I use. If I recall when at Lockheed, Carbon Fiber aka Composite Graphite is much much stiffer. While I do not think the chassis is flexing, I can see were stiffer is better so the suspension components can do there thing.

What do you think?

It's a guy thing. You 2 suffer from it aloo. Make something better. Maybe I should listen to Grandpa and "not fix something that ain't broke". LOL

I just think we can get this thing to get harder off of the corner. I know I can never just mash it and expect it to hold but there has to be a happy medium.
No problem adding washers to raise the body. We can get the body into all kinds of weird angles Mark. No rules against that at either track.

I do wonder if the new engine is the proplem. We got used to the old one and now with a new high HP motor more troubles have reared their ugly heads. If I recall, we did not have this much of a push problem before.

Motor wise we can do one of 2 things. Put the old motor back in but install the slide Carb which gives a much better throttle resonse instead of the stock Barrel carb for more bottom end punch or leave in the Novarossi and put the Barrel carb for less bottom end response. Maybe the Novarossi is giving us to much bottom end punch?

I feel it is an Oreo and chassis deal and we need to find the right combo for the 2.

Tomorrow I am gonna adjust the body and do the spring change based on your and Hardscrabble's input.

Just proves how much Cup teams need an Oreo guy and a Chassis guy.

On a different note. How are the baby Torts doing? Good news here. Doc said the last bone graft is taking!!!!!!!!!!!!!!

THANK GOD!!!!!!!!!!!!!!!!!!!!!!!

Our best to Roxie
 
Stop The Presses......CRS was acting up again.....If we trim one side more than the other we blow the roadies. Just get the front end lower than the back to change the deflection. HS sez 5mm and I don't do mm's Talk American goldernitall HS. :D

I'm saying get the the nose down as far as ya can. The greater the hood angle the better. The worst that can happen is that the front bottoms out going in and bends the valance under rather than trim itself.

As for Ackerman....If it's already adjusted all the way, toe out the left front and see if you can still hold on to it on the straights. It's gonna be squirlly (how ya speel dat).

Don't change bodies yet.....everybody loves new tires.....but if you do, for gosh sake do not offset the holes and put em both in the middle instead of off to the left. At least keep em lined up on the left if nothing else. I know the standard practice is in front of the head but I really don't think it's all that important. Besides, a hotter cylinder/piston produces closer tolerances which in turn produces more compression if I'm not mistaken.

And yes we can get to mash the gas coming off. We've always relied on turning in with the passing at the end of the straight. What we want is to just get a door underneath going in, hold the bottom, and scream away coming off. If they can't catch us coming off, they'll never catch us going in. We got the best turn-in out there but giving up a bit of in to get the out might be the key.

Speaking of screaming.....TOO TIGHT TOO TIGHT TOO TIGHT......It's the main complaint. Just once I want to hear Loose Off. :D

Tires.....Just for spits and giggles (if ya got one) throw a foam on the left front for a short run. If we are not gripping the left front it won't be wearing as much anyways.

Motor.....Go with the Novarossi/Barrel carb if it doesn't give up too much at the top end only as a last resort.

Frame Flex....Don't worry about it yet. The only time that will be a factor is when we change tracks....If sponsor has more money to spend get a bigger spring or tire variety.

Video Tape!!!!!

Set a camera up facing the nose of the car just past the apex. Gots to know what the rollover factor is. That's why folks paint a bright stripe at the bottom of the valance.

Ohhhhhhh kay..........

Great news about the fuse....gosh it rhymes.

All four hatchlings are still alive along with 3 of 4yearlings. If there are more hatchlings in the yard I haven't spotted them yet.
 
Not 5 mm , .5 mm. That's one half a mm or roughly 1/50 of an inch. In scale it equals about a quarter inch.......

Got used to metrics working for a Swiss company, once ya get used to them they are a lot easier to work with than SAE, IMO.

Keep the hp, if nothing else ya get more straightaway speed and most of the time cars handle pretty good in the straights.........LOL
In the turns the man upstairs gave a right foot, use it......course in this case I reckon it's some finger or another......

I believe we can get this thing to handle all the moxie the engine can deliver, just gotta find where the combo is off. It is not off by much I don't think.

As for Ackerman, the left tire should turn more than the right. The left side is following a turn of less radius than the right, therefore it has to turn more to follow the arc.

Anything we can find out which will tell us how much each tire is working will help. So will finding out how much the inside of the tire vs the outside of the tire is working. Would be expensive I guess, but if ya mounted up a set of the real real soft tires and ran a handful of good laps you could likely see the tire wear real easy.

You guys keep working the oreo, whatever you can find there helps. If needed the chassis can sort out to match.
 
As for Ackerman, the left tire should turn more than the right. The left side is following a turn of less radius than the right, therefore it has to turn more to follow the arc.

Okay.....I'm a dummy.....Have never even heard of Ackerman. Was I correct to assume that toeing out the left front would help to line the wheels up in the turns and is this really the desired result?

I was guessing this is what we wanted.
 
That is really what Ackerman does, it increases the amount the inside tire turns in relation to the outside tire. Works going either left or right but the good thing is it has zero effect when the car is going straight.

Should be running a small amount of toe out to help keep the car stable in the straights. It also helps turn in.

Bump steer works the same way a little. As the front a arms move, the toe will change just a bit. By setting it so that get a bit of toe in as the right front compresses and a bit of toe out as the left front decompresses you get bump steer.............tricky to get right but can make a world of difference/
 
Ok.....glad I seem to kinda sorta understand. Guess I better stick to the body work :D

And yer right, as experinced as Mongo is at racing it's just a matter of dial-in. Lowering bottom end punch has got to be a last resort.
 
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