3rdgenmaro

iTrader: (9)

I know these cars are not very popular for circle track racing, partly due to the rules packages many tracks have, but one local high banked dirt 1/2 mile just started a pure stock class where these cars are legal. A couple of buddies and I are going to go play. None of use have ever circle tracked raced, but we plan on doing our research through the fall and winter and come out next spring for practice.

With the low cost of these cars and being familiar with them lead us to a running and driving 91 RS 305 5 speed for cheap (no title). Right now the plan is to use most everything drivetrain wise as is and dial the suspension in. Once we get the handling good, then we will work with getting more power out of it.

The car is mostly complete at this point as it was from the factory. I have started doing a lot of reading on how to setup a car for circle track, but once again I have no experience. I thought this might be a good place to get some information from experienced people. I would love to hear anybody's suggestions on where to start with a basic suspension setup.

The track rules are pretty open, but the main suspension ones are:
1) All suspension components must be stock and in stock location.
2) No lightweight suspension components
3) Springs may be heated or cut
4) Max spring diameter 19mm, must be same on right and left side.

Also mentions stock brakes with no adjustment, max 8" wide 15" wheel, can have different tire sizes.

Any suggestions on a good starting setup?

GCrites80s

Can you reinforce the stock stuff by welding in metal? It would be really nice especially on dirt to keep those parts from flopping around.

red rock

iTrader: (2)

The biggest problem will be, these cars are light when you strip it bare bones, so without your rule book to read through, tire stagger and tread design, and tire pressure will be about all you can work with. Pure stock class is usually just that, pure stock. Is there a weight limit for car and driver? What gear ratio in the rear?

3rdgenmaro

iTrader: (9)

It doesnt say you cant, but it also says stock components only. So I think that would be a stretch.

Minimum 3200 lbs with driver. Not sure of gear, probably start around 3.08 or 3.23 and only use up to 3rd gear. Rearend has to be stock for make and model.

The only thing else like you said I could see us working with is sway bar size and springs. Right now Im thinking about trying what is on the car now and going from there.

red rock

iTrader: (2)

Gut it out, weld in a roll bar cage, paint it black with an Earnhardt #3, get in and hang on. Pure stock is the cheapest and funnest way to get into racing. Send some pictures on this post when you get it done. BTW, if you have a choice, use the 3.23 or get a 3.42 gear if you can.

3rdgenmaro

iTrader: (9)

I thought about the 3.42 at first, but not sure how it will do. Dont want to have to shift to 4th unless I have to. I dont know, going to be a trial and error type of deal I believe for a bit. Thanks for all the input.

Anybody ever preloaded the chassis to induce some crossweight before welding in the cage? I thought about it, but since we are starting out, I think a neutral square chassis would be best, especially with the flex these cars have.

red rock

iTrader: (2)

Depending on the size of the track, 1/3 to 1/2 mile track on dirt, a 3.42 gear in the rear and second gear in the tranny is all you will use.

basiccamaro

You can't just say "I will need 3:73 Gears" or whatever. And if you want to be competitive at all, you can't use an automatic.

You need to find out the best final gear ratio for your car and track. Then you attempt to get your FINAL DRIVE ratio as close as you can to that. You don't shift on an oval track except to get on or off the track. Often, in the lower classes, you need to use one of your lower gears in the tranny all of the way around the track . But whatever gear you are in, you need to know it's ratio and multiply it by your rear end ratio to get your final drive ratio.
Unless modified, like the torque converter-less powerglides with a quarter turn fluid bypass valve, an automatic will "let loose" when you let off the gas going into the corner and offer no engine braking whatsoever. This will feel like another car is shoving you into the corner much faster than you can go. You can hold the automatic in a lower gear, but that will lead to other problems as well. And you probably won't have the correct final ratio anyway.

That's just that part of it. The 3rd Gen front end is very hard to work with for an oval track car. The positive and negative camber and castor numbers are much harder to achieve than with say, a 2nd Gen front end.
There is a thread on here where somebody else did a nice job building a 3rd gen for a circle track car. See if you can search it up.

3rdgenmaro

iTrader: (9)

Yes we are going to start out somewhere around 520 to 570 ratio. Probably 3rd gear max. We will wait and see. Right now Im not even certain what is in the car. Not even sure if it is the rearend the car came with. All I do know is that it has been painted, open, and disc brakes.

Yes I have seen the street stock build on here. Saved it and many pictures from it.

red rock

iTrader: (2)

Good luck! And keep me posted.

SlickTrackGod

Strip the car of evertthing not needed, then once finished you can add lead inside the left rear storage hatch to make race weight with full tank at aproc 3212lbs- leave a 12 lb margin for driver and scale inaccuracies.

800 lbs fronts, 150 lr,275 rr. Run about 2" static stagger. Find a blown lf strut (no rebound). Rf go about 7/5 valving. Left front 0/5 if you can swing it. (Otherwise use a good cheapy rf and a blown lf strut.)
36/24 swaybars with custom endlink that you can shim for preload-add washer stacks if limited on rules. You will want to extend the lf swarbar link to get at least 53% static cross with a shitload of preload on that extended LF link lifting presure off that wheel. This will give you cross and rate.

Dean.
NASCAR supertruck crew chief

SlickTrackGod

Run a powerglide trans wit a fluid break left pedal and a direct coupler (no covertor) this is standard practice and cheap in cost

Use some cheaper rear adjustable shocks if you can- max the lr reound, min the rr rebound.

Give it a practice and post up how you are doing. Ill help you tweak it from there.

Edit to add- almost forgot, weld up any pegleg or posi and make it a spool.

Leave the right side fender heights at aprox 27" front and 28" rear when tires aired up and swaybar preload complete. This will keep a decent lca angle abd hopefully a little roll understeer of the back axle for drift stability in corner set.

AM91Camaro_RS

You don't want the chassis in a bind when you weld the cage in. You adjust cross weight with suspension, not chassis.

3rdgenmaro

iTrader: (9)

Thanks for the replies. Dean Im glad you seen this and posted in. That helps a lot. I'll see what we can do. And we will post up as we go. We wont get started building the car until october or november, but right now we are putting in the time researching it.

Powerglides arent legal, neither are any adjustable suspension components, but it is worded pretty open and I love the gray area.

SlickTrackGod

If its a NASCAR grassroots series then make sure your read the rule book. NASCAR in all levels of circletrack always has a line in there somewhere that if it is not specificed in the rule book then it is not legal. Just because its not tlaked about or regulated DOES NOT mean you can do it.

Most back runners and/or new entrants will be fudged through tech bay inspections and some illegal things intentionally overlooked just to make the race quanity if cars more for crowd pleasure- once you become a more of a threat in points you will fall under more strict scurtiny. Top 5 finishers generally always go to tech quarintine after the race and the NASCAR officials will call for a random inspection of a certain part(s) of their choice for all top five in the same inspection criteria. if they call for Carburators- then all five are subject to a "no-go" dropped into carb bores, etc. They may want an intake and exhaust valve spring to check pressures, they may want a rear alxe to make sure it's not turned down and lightened, they may want the diff pulled to make sure no aluminum parts. Just be aware before spending money on things you do not see listed.

The main thing in the last 5 years is the manitude of top runners that have cheater spec motors. It is impossible to regulate this and EVERYONE is doing it. All it did was add cost to everyone. If you do not do this cheat you will not win. Read up on it. That is all I am saying. You will know right off the bat when you see the top 5 cars with a rich overlap of raw fuel igniting out the tailpipe just prior to corner entry. They don not have a way to quickly and very accurately inspect cam duration in tech, howeve they do check lift obviously which is very easy. If you don;t do it? just know everyone else is and you are not going to be competitive. in a spec motor class.

3rdgenmaro

iTrader: (9)

I really appreciate it. This is not a spec motor class, but a bottom entry class. The track we are going to run mostly at is FASTRAK for the late models, but I assume no sanction for the lower classes. However, there is a local asphalt track that this car will be legal for that is NASCAR if we decide to go that route. Thanks again!

3rdgenmaro

iTrader: (9)

Dean,

I have been doing a lot more reading, and I wanted to ask if you seen that this car will be primarily on dirt. Some of the things Ive been reading contradicts some of the things you mentioned. (sway bars mainly)

Thanks

SlickTrackGod

Youa re most likely reading about classes that use coilovers or weight jackers of some type. They use very small or no sway bars at all. You do not have that liberty. You have no way to throw cross weight at the car unless you just use a real heavy RF spring- then you'd better go to about 3" stagger to get it to rotate under throttle going in because you will be tight as all hell under braking and be yanking the nose to the right. A late model or a modified are entirely different animals then what you are building.

A chassis setup is an entire marriage of settings and componants (spring rates, shock valving on both comp and rebound on each individual corner, chassis rake, chssis ride heioght pertaining to geometry and roll center migrations. there is so much to consider that you can NOT take one thing here and another thing you read there and try to make sense of a bunch of different trains of thought- it does not work that way. Everything need to work in sequence, and if it is not then you change RC's and cross until it's optimum. If it is having issues say going in and not turning then you up the right front comp valving one or two clicks to get the dynamic result you are looking for- if it still is not effective enough you change spring rates and start again sorting RC and cross. Preloading a swaybar helps the car get off the corner more tight. Wit no cross you will be way loose expecially running any stagger about 1.5"... and way tight under braking with chatter and a hard to control wheel- the car will walk all over the place like it's on an ice skating rink.

You have to use what is within your rules.

3rdgenmaro

iTrader: (9)

Thanks Dean.

That is my problem. Im trying to learn so much about it at once that things start to contradict. But I trust you and I will keep up reading and we will see where we end up when we get on the track and go from there. Thanks again.

SlickTrackGod

Dirt track setups are very dependant on the condition of the track. It can vary so much more than asphalt. The wetter the track the more grip you actually have. With that said, you will probably be running on very dry dirt surface with blackish rubber laid down on the surface. This makes for a slippery track. The more slippery and hard the surface the more you want right side spring rates higher. The sloppier the surface you want more weight leaning over the right side (more body roll) to promote bite with the chassis pitched out (in a drift type position like a sprint car. On a latemodel NASCAR with coilovers you run a very soft swaybar to promote this roll and also get the rear end to articulate up over-BUT!!!!- on those car you dial in alot of cross with coilovers and you steer them with the throttle, You have no cross with your platform becasue of limited rules and conventional springs, You can take hours upon hours and get the chassis set with welded shims above the springs on the LR & RF and frind a **** load of conventional springs in a junk yard to cut and test on a high dollar spring rrate checker, but do you have that kind of time knowledge and equipment? Not many of us do. The swaybar trick will get you cross. Yes it limits body roll, but you will most likely be on a harder dirt track....and, you have a high rear roll center which will automatically canter the inside rear up into the air. You can not use an adjustable panhard rod height setup to fine tune you car within limits of your rule book.

You are most likelu going to have to use a setup that is half way between an asphalt and wet fast dirt setup. You will be driving probably more for asphalt type traction but more geared towards and overdriven asphalt condition coming off loose. but going in tight (not going in like a conventional dirt car or sprint.)

3rdgenmaro

iTrader: (9)

Thanks again.

Yes the track we will be running is known to be smooth, dry, and hard. It is fairly high banked and they had been running this class near the end and the track had started rubbering up. More so on big latemodel race nights.

GCrites80s

Probably not going to want to be sideways much if at all in this class, correct?

GCrites80s

Are you going to be running a spool?

3rdgenmaro

iTrader: (9)

No, I dont believe there will be a lot of sideways in the turns, but Im not sure.

Yes, will either run a spool or just weld the spiders. Havent decided yet. Was able to figure out it has a 3.08 with a 21mm rear bar. Hadnt had a chance to check the front.

Trying to figure out now if we are going to sell the disc rearend and put a drum one under it. Only reason to swap would be we could recoup some money selling the disc rearend off and if we ever break an axle, another drum rearend would be a quick a cheap replacement. Any thoughts on keeping the disc or going to drum?

GCrites80s

Brake bias adjusters not allowed right? Stock the rear brakes don't do much on these cars. Obviously if you dialed in more rear brake they're going to get hotter.

3rdgenmaro

iTrader: (9)

Right.

After checking some pricing at local junkyards, Im just going to keep the disc rear under the car.

GCrites80s

Having never done this myself, I do wonder if you switched to drums in the back you could run different size wheel cylinders to change the brake bias without detection. It wouldn't be "adjustable" and I doubt there'd be a wheel cylinder exam.

People more knowledgeable than me please give us your thoughts.

3rdgenmaro

iTrader: (9)

Looking at front MOOG spring rates from this site, MOOG #5662 (listed at 748# or 648#) would be the closest to 800# stock replacement front springs I can get and remain right at the 19mm (or .002 over) max diameter rule. Going well below the 19mm rule for MOOG would be #5660 with 598#. I need to look further into other aftermarket springs.

MOOG 5665 rears are only 107#.

According to: http://camaroforums.com/forum/93-02-...atabase-74357/

For the rears, it looks like several options would fit, but I have to research the spring diameter. Might get lucky enough to find more detail on the rears and find two that are similar diameters but with the different rates.


I dont think that finding a blown lf will be hard. The way the car rides now, all 4 corners are shot. Since I cant run adjustable, I was thinking a new KYB GR-2 on the right front. As for the rears, Im not really sure what to do. KYB GR-2s or Gas-a-justs?

Any comments?

SlickTrackGod

Don;t go spending a lot of money on things because you will always need the option to fine tune with additional parts. It is a process to find the sweet spot combo of components. What I am giving you is a baseline setup to try and work off of. Try going to the junkyard and just removing multiple springs from cars that look like they will work diameter wise and get different spring wire makeups (even if you have to trim height to fit which you will have to do) it is all about budget racing. You want to try and get a larger RR spring then the LR spring to migrate the roll center to the right to weight the LR tire and keep the LR chassis weight from going up and over onto the RF going into banked corners. Just throw Gas-a-justs on 3 corners and a blown shock on the LF.


Keep in mind the simple rule of thumb that if a chassis is stiffer sprung then it is easier to control in a drift type situation, however, the stiffer sprung also looses mechanical grip. You are on dirt and will be doing a lot of chassis bobbling about on the course, stiffer will keep the wheel more predictable expecially if you encounter ruts.

3rdgenmaro

iTrader: (9)

Just wanted to give a little update. Will be installing the cage in the next couple of weeks. Been getting some stuff together. I will start a build thread later on. I keep looking back at this for setup input. We will see how that goes alittle later on. Thanks again Dean and others that have gave input.

3rdgenmaro

iTrader: (9)

I have a stagger question. Do you adjust stagger by tire pressure or by tire size? Reason I ask is that with our tire size limitations, it is getting hard to find a tire size that will give us 2". Looks like 255/70r15 is the most common and easiest to get. Along with 235/70r15. But that gives us 3" stagger, assuming all else is the same.

So do you just give the right side alittle more air pressure to increase the stagger? Seems like too much/little air pressure would affect the contact patch too much.

Dean? Any other circle track guys? Thanks

SlickTrackGod

Both, but you are not going to do pressure stagger with radials. You may get 0.3" dropping the left down 10 psi but that's about it. To get a static 1.3 I use 1/2" difference in carcasses and then air up LR 15 and RR 25- a pretty standard thing in racing on bias ply racing slick

GCrites80s

You gotta run radials? The bias plies are much more tunable and let you go by circumference with a measuring tape.

SlickTrackGod

Also remember that choosing a smaller matched pair in size will pick up a little gear (rpm) if needed for advantage.
eaxmple-

Instead of a 255-70-15 right and 235 left, might want to consider a 245 right and a 225 left to pick up gear.

Think of dynamic footprint, not static. The less pressure in the left will increase static footprint as well as increase psi will decrease static right footprint. But in dynamic form in mid corner they will be closer to matching when the chassis is set in lateral force to the right. Cross weight balances stagger. Not a lot of cross? then not a lot of staggar- is a good rule of thumb. 2" is a lot.

I recently ran an enduro car for fun. The owner who is my NASCAR team mechanic told me his son says the car is normally loose in corners. I had no practice in the car at all, just geared up and raced it. I ran over and grabbed the largest of the largest 2 of the 4 tires he had on the car (they were al mismatched scrapyard tires anyways- cheap form of racing) and threw them on the LR and RF. Berk (Engongam- Ramjet502 1991 TA)) on these boards co drove with me (visiting me here in SO Calif from Istanbul Turkey) He drove the first leg 15 laps, I drove the second 15 laps. Out of 37 cars we took 2nd. Just a quick example on how chassis dynaimc knowledge will help anything.

ps- This is what happens when you try and bump Doc Sake wide trying to help your friend stay in first place (@ 11:55). I should be teaching the LAPD how to properly do the PIC maneuver.

Watch the orange car get waxed @ 12:00

3rdgenmaro

iTrader: (9)

Thanks for that explanation. Makes more sense. Im hoping that I can find some different sizes at a u-pull yard so that I can get an idea of things.

Gcrities: The rules state "
'TIRES: Any 70, 75 or 78 series street legal DOT res. No high performance, truck, trick or direconal res. No DOT racing res.
(Asphalt track cars may use their track res) Tires do not have to be the same size."

I looked some, but wasnt able to find one that I thought fit the rules. But I may have overlooked something. All i know is that a lot of guys in this class run either the Cooper Cobra or Mastercraft Avenger. That was why I mentioned the sizes I did earlier, seems to be the only sizes made. But I can see now where it would be good to have a 245 to be able to put on as well. Thanks!

Also, the rules allow either racing wheels or stock wheels. But they also require the 1" lug nuts. Which doesnt make any sense to me since the 1" lugs I have seen are all 45 degree seat and all the stock wheels are 60. Guys have told me they run the 45 lugs with stock wheels without issue, but that to me just seems crazy. So its almost like you have to run racing wheels, which will be about $50 each versus $20 (if I can find them for the stock).

Am I right on it being crazy to run the 45 seat lug on the 60 seat stock wheel? Or is it really ok?

GCrites80s

Ah jeez that tire rule is written in an ancient manner. So basically you have to run skinny tires. And who's making a DOT bias ply that skinny in 2015? At least those Kmart Mastercrafts should be cheap. It says no "trick tires", does that mean you can't cut them? Are other guys cutting their tires?

3rdgenmaro

iTrader: (9)

Not that I know of. But I dont know for certain. The general rules section mentions no sipping, grooving, or soaking allowed.

What is your take on the lug seat? It seems like nobody sells used wheels and I hate to spend $200 on 4 new wheels.

SlickTrackGod

You've got fire/safety close by. Id say screw it, just torque 'em on there and go for it. If you would have seen the 3 lugs I had spaced out on that RR of the enduro car so the tire would not hit the strut- you would 've about sh*t LOL. I figured if it came off it just make a crowd pleaser.

SlickTrackGod

Here, is this nuts or what (pun intended)

I pulled a lugnut off the LR (so only 4 of 5 there), and then used 3 of the 6 first on the studs in a triangle pattern to space the RR out 3/4", then used the last three on top of them to hold the wheel on. The RR was so bashed in the wheel was rubbing the strut when torqued in place.

Sometimes in life you just gotta say "what the heck"

3rdgenmaro

iTrader: (9)

Now thats funny right there. It does seem to be one of those things that everybody is doing with a pretty good sucess rate. I guess you are more likely to cut a tire or get knocked into the wall then to have a wheel come off because of the lug seat.

3rdgenmaro

iTrader: (9)

Getting closer and closer. Quick question though. What would be a good alignment setup to start out at? I was thinking as much negative camber as I could get on the passenger side, and maybe as much positive on the drivers????? Maybe 1/8" toed in??? Caster???

Thanks!

SlickTrackGod

Camber-do as you assumed. max neg rf/ max pos lf.

Toe- between 1/8 OUT up to 1/4 OUT. More track grip equals less oversteer= higher side on toe out range.

CASTER-RF MAX OUT. Hopefully this will be 5*, maybe 5.5.
LF caster depends on track conditions and track shape/length. the more you go straight AND the higher the corners bank= less steering angle= less caster split..However, the more oversteer= less caster split also.

A tight grippy no bank 1/3 mile oval use 2 or even 2.5* lower LF setting then RF= This helps the car turn WHILE ALSO helps the LF spindle not to lift the inside chassis in tight corners.

long course or oversteer use 1* split.


Just understand that even these setting can tighten or loosen the overall chassis etup so other values like shocks and springs and rc's as well as fine tuning with swaybar preload need to change as seen fit. I am giving my best guess at starting baseline values.

SlickTrackGod

ps- Ive been building an asphalt enduro car for myself the last 3 weeks. im almost finisher. a 98 Dodge "joe dirt" Neon. ... and yes it will be mopar hugger ""neon brite" orange.

3rdgenmaro

iTrader: (9)

Good thing I asked! Thanks Dean for the baselines. That really helps.

3rdgenmaro

iTrader: (9)

I thought that shortening the left link would take weight off the left wheel??? What am I missing?

SlickTrackGod

Yes, sorry, I deal with a lot of different cars. The 3rd gen bar comes in on top so yes shorten the link to pull the weight off the LF.

3rdgenmaro

iTrader: (9)

Well we have an initial setup on the car. Practice is this saturday. With time constraints we are pretty close to Dean's recommendations. We will see how it goes. We have some plans for minor changes depending on where we start.

How is the "joe dirt" neon going Dean?

SlickTrackGod

How'd everything go? Hope you are having FUN- people tend to forget that about racing.

Joe Dirt Neon had a few electrical gremlins we just finally sorted out. One of them being a PCM problem which turned out to be a PCM ground wire to the ignition key circuit which kept shutting everything down on left turns. THe weight of the key ring was tugging the cylinder to the right of all things.

She's been track tested and handles unbelievably great for a rule restriction stock suspension. Ready to go win some money in a few weeks with it's first pro race. Sponsors are all on board - Racetrans, AutoAdsToday.com, and Vertical Doors.

TIme to go smash this sucker up...lol

3rdgenmaro

iTrader: (9)

It went great. And a ton of fun. I was a nervous wreck before hand, but once I was on the track it felt great.

I took the car out in the first session. Track was good and tacky. I knew every turn that I could have went a lot faster, but then by the time I got through the straights, I was afraid I was going to fast so I would let out and end up slowing down too much. It was just a different feeling than I thought it would be. My cousin ran the second and third session and had the same feelings on his first time out. Just intimidating when you are running wide open towards a huge turn on dirt. You want to let out of it thinking there wont be any grip, but there was.

By the end of the day we watched a lot more cars go and figured out that the only thing going to make us faster at this point was seat time. His second run he picked up 2.5 seconds just because he knew it could do it. We just both have to get more seat time.

We had a ball. Stock gearing should be about right. Car was straight in the turns, but that could be where we just arent pushing it enough yet. This weekend went great though. We wrote down some stuff, kept everything the same, and worked just towards getting the feel for it. I love it. I cant wait for saturday to get back on the track.

I did notice one thing, last session the track was hard, dry, and starting to take rubber. He was pushing it pretty good and you could hear the tires starting to squal at times in the turns. Not knowing anything, I just took my hand and felt the tires when he came back in. Just to get an idea. Right front was doing what I expected with a camaro. Outside edge was hot and going colder towards the inside. I figure the lack of camber adjustment on the stock mounts. Car didnt act like or look like it was rolling over.

But either way, my plan this weekend is to start off the same as we was and just get more of a feel for the car. Since this will be a race with hotlap qualifying, Im just going to keep slowly pushing it faster and faster, then see what the car starts doing as we get fast enough to really tell.

Or is that a wrong way of thinking?

SlickTrackGod

Good deal. I would always "baseline" the car and make changes from there according to track conditions. That way you have a good starting format. If you see the track always going tight like that with lots of rubber being laid down then change the baseline setup- maybe a slightly larger rear sway bar. For the car going tight, try airing up the LF and RR 4 lbs each to take out some cross and lessen the RR grip contact patch size. IF the tire is getting too hot the air up 2psi RR and LF, and 2 psi down RF and LR. etc. You get the point. Little air pressure adjustments can show pretty significant results.

If the car really goes tight then a spring rate change is in order. Try going a spring rubber in the LF or RR. Pepboys sells 5" 100lb spring rubbers for about $10 each you can put into the LF and give it a try.