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Posted

Hello,

 

I am new to the board and I have been searching the posts here for awhile now. I am looking to eventually compete in CMC with my 1983 Mustang (no applause, please) but I gotta learn to drive it first so I am gonna go the HPDE route first and go from there. I love the idea of close competition on a road course and CMC seems like the place for me. As you can see by my location, its kinda hard to make a race (unless someone wants to run a CMC race at Road America). Therefore, it is easier for me to ask questions in this venue instead.

 

To the point, I have a few questions about the current rules that I have read and re-read. So here goes... (please bear in mind that most of these questions pertain to Mustangs)

 

Aftermarket "stock type" forged or hypereutectic pistons (i.e. Diamond, JE, or Keith Black) allowed?

 

Can the compression be increased beyond stock (8.3:1 in my case)?

 

Can I use my original dual snorkle air cleaner?

 

Can I use manual steering? Flaming River rack and steering shaft?

 

Can the engine be neutral balanced (just wondering)?

 

Must the quad shocks and all associated brackets be retained?

 

Can the cam timing be advanced or retarded to make more power within the HP and RPM limits?

 

Can we use retrofit roller tappets to use rollercams in early non-roller blocks?

 

Can better valvesprings and retainers be used? Titanium springs and retainers?

 

Can we use the Holley Secondary Metering block conversion kit?

 

What is the factory RPM range for the Ford 5.0?

 

Why can't we add on a rev limiter such as MSD PN 8728? I would feel better with something like that. It adds no power but it does save an engine in the event of a worst case scenario?

 

I am sure there are obvious answers to these questions but as I am part of the uninitiated, please be kind

 

Thanks for your help,

 

Paul

Posted

Answers:

Aftermarket "stock type" forged or hypereutectic pistons (i.e. Diamond, JE, or Keith Black) allowed? YES

 

Can the compression be increased beyond stock (8.3:1 in my case)? YES,but to no more than stock later model 9:1

 

Can I use my original dual snorkle air cleaner? YES

 

Can I use manual steering? Flaming River rack and steering shaft? Yes on the steering, no on the flaming river.

 

Can the engine be neutral balanced (just wondering)? No, 50oz is factory,but you can balance it.

 

Must the quad shocks and all associated brackets be retained? NO

 

Can the cam timing be advanced or retarded to make more power within the HP and RPM limits? No

 

Can we use retrofit roller tappets to use rollercams in early non-roller blocks? Yes,roller is Ok

 

Can better valvesprings and retainers be used? Titanium springs and retainers? No reason to spend the money,so factory ones work great.

 

Can we use the Holley Secondary Metering block conversion kit? No

 

What is the factory RPM range for the Ford 5.0? See the rules.

 

Why can't we add on a rev limiter such as MSD PN 8728? I would feel better with something like that. It adds no power but it does save an engine in the event of a worst case scenario? Cost/electronics,again no reason for it.

 

Thanks for the questions,hope I helped you out a bit.

Tony Guaglione

Posted

Paul, as a newbie, let me chime in.

 

If you think of building a car from the ground up, you will run into a lot of obstacles. If, like me, you are used to building a car UP to the rules, if those rules mean the CCR and CMC 2K5 or run what your wallet allows. Both are a set of rules, if you think about it.

 

For CMC, think of it as taking a street legal car and dressing it down to meet safety requirements and a level playing field.

 

To help you understand what parts you can use or can't, think of it as a diet ... if it tastes good, spit it out. On the street, if it's a considered a hot part, chances are good CMC doesn't allow it.

 

I don't envy the director's job. It must be tough riegning in a bunch of hot rodders ...

Posted

Tony,

 

Thanks for such a fast reply. I appreciate it. Your answers helped but like many answers they lead to more questions. If I may pick your brain further...

 

The Flaming River rack is not legal but is the steering shaft?

 

The cam must be run straight up? Can we degree the cam then?

 

Are timing gear drives legal?

 

I read the rules pertaining to Factory RPM Limit but saw no specific number limit. My stock tach redlines at 6,000 rpms so is this the Factory RPM Limit?

 

OEM harmonic balancer is all that is legal?

 

The factory valvesprings are good up to 6250 with no valve float?

 

Is a T-56 allowed to be installed on a FOX-3?

 

What are the best Ford exhaust headers to look for? My car currrently has Hooker headers and I know that they aren't legal.

 

I currrentlty have Holley's Quick Change Secondary Spring Kit on my 600 Holley 4160, is that legal?

 

The rules say that no competitior shall be subject to any form of engine tear down. Does this mean that the valve covers won't be removed even though they are in sight of the inspector?

 

Can we use the Fuel Safe late model Mustang specific fule tank SA110A? With the use of that tank can an electric fuel pump be used?

 

Thanks again for the help,

 

Paul

Posted

mitchntx,

 

Thanks for your insight. I guess I am accustomed to looking for the edge so I can walk it but not fall off. I did alot of reserach into NMRA Factory Stock Drag Racing a couple of years ago, thinking I could go in at a friendly entry level. Then I started adding up costs and figured out what the rest already know, it ain't stock and it ain't cheap. $10,000 for a competitive professionally built motor. I am not in for racing in a "stock" class that makes the budget guy nothing more than field filling fodder. In my research I found out a few tips/tricks to get the motors to make more power within the rules. Lightweight resiprocating mass was one and lightweight valvetrain components the other. Just an example. Sorry if this does not make sense I keep getting interrupted during my typing.

 

Thanks again,

 

Paul

Posted

Over the last few months I've banged heads with several of these guys and against the wall.

 

It took me a while to figure out (like I really have) the intent of the INTENT.

 

Posted

mitchntx,

 

The "INTENT", as I see it, is to have fun. I am not trying to bang heads with anyone. I just don't want to cross the line with modifications and find out raceday that I can't run becasue of it. That's why I am asking so many questions.

 

I will be the first to admit I have gotten caught up with the magazine write-ups expressing why you must have this high dollar go-fast part. Eventually my mindset became clouded to the point that if I don't have any or all of these parts my car won't be fast at all. This is not the magazine's fault but my own lack of practical experience. I haven't been out there working with what I got and improving it from there. That's where I have to improve.

 

Paul

Posted

While smoe series operate on the premise of "If it ain't in the rules, it's legal" CMC goes by "it it ain't in the rules, it's illegal."

Posted

Take the money you would spend on the hot part you want and buy steaks and beer for the region at your first race weekend. It's the rule.

Posted

Right on Turbo Tuna (great handle) ...like you say every mag we pick up is page after page of GO FAST GOODIES or add ons that look cool..all of these items may or may not work, but WE dont need 'em. The real CMC challenge is to learn how to drive a all american stock car the best you can at different race tracks with a bunch of racers havin the time of their lives ! The best $ spent is on a new set of shaved TOYOS ( 2-3 sec lap) and after a couple podium finishes the TOYO dollars will help pay for that new set of tires...Thats my story and IM stickin to it .. CMC # 6

Posted

Tony,

 

If you have a 1979 Mustang with a 302, the factory balance is 28 oz-in, so under the rules allowing update/backdate of components, either balance factor should be legal in CMC.

Posted
mitchntx,

 

The "INTENT", as I see it, is to have fun. I am not trying to bang heads with anyone. I just don't want to cross the line with modifications and find out raceday that I can't run becasue of it. That's why I am asking so many questions.

 

I will be the first to admit I have gotten caught up with the magazine write-ups expressing why you must have this high dollar go-fast part. Eventually my mindset became clouded to the point that if I don't have any or all of these parts my car won't be fast at all. This is not the magazine's fault but my own lack of practical experience. I haven't been out there working with what I got and improving it from there. That's where I have to improve.

 

Paul

 

Don't misunderstand ... I was/am standing in your shoes a couple months ago/today.

 

You seem to have a good grasp on things. My comment was about my situation, not meaning to imply yours was gonna be the same.

  • Members
Posted

Paul

Welcome to the family man! Hey, no worries, like Mitch said, we've all been in your shoes. Almost everyone tries to figure out how to build their car to win. What all these guys are telling you is you don't need to bother! We've gone to great lengths to ensure CMC is about driving, and having fun...so many aftermarket parts (most engine parts) are not allowed. Most of these things would make a car faster...but then everyone would already have it, so we'd all be about the same speed anyway.

 

To answer your other questions specifically...

 

OEM manual steering is ok if you want it (not recommended!!), no aftermarket steering racks/shafts.

 

Cam timing must be within factory spec.

 

No gear drives unless Ford put them there.

 

I'm not the Ford guy...I'm sure Ford had a redline stated in the manual for every year 5.0. Find the highest (non Cobra) one, and thats yours.

 

Yep, OEM balancer is it.

 

Tony revs the crap out of his 5.0 and never has issues with it...just ask him! Seriously, the valve springs will be fine.

 

Yep, you can use a t56, but why would you? You'll never ever use 6th with our gear ratios and power levels, so you might as well not carry around the extra weight. I'd stick to a WCT-5 with the good 5th gear set.

 

No clue on differences between the years on exhaust...

 

No internal carb mods. OEM carburator, or spec engine option. (do yourself a favor and get a modern 5.0 efi )

 

Yep, technically you'll never go through an engine tear down, so you can probably get away with a lot of internal mods. You can probably also set things up to dyno under 230 once a year when needed. Then again, you might get caught. You might go to a track with a dyno on site. Or you might get hooked up to a computer that reads what your PCM is doing. Or you might get hooked up to a portable dyno. Or...??? There are ways of finding out.

 

You have to ask yourself why are you going CMC. Personally, I think the shame and lack of trust from my fellow racers should I ever get caught intentionally cheating far outweighs the benefits of a few extra ponies. I've made some great friendships at the track, and I know a the fact that we're not hiding things from each other is a big driver for those friendships. You simply can't build trust when you're always sneaking around. We're here to have fun after all...and bragging that I beat you when I know deep down it was my car that beat you...well, that's just not my definition of fun.

 

Yep, that fuel safe cell is legal. Its wicked pricy though!! Remember, if you go with a fuel cell you must replace the bladder every 5years per Nasa's CCR. Personally, I'd get a much less expensive cell ($5-600 for a regular old fuel safe sportsman) and fabricate your own mounting. External electric fuel pumps are ok with a cell.

Posted

Al,very good and correct comments!

 

Hi Matt...Ok, so the if the early Mustangs were 28 Oz,then no problem you can balance with 28 or 50 Oz.

 

Tony

Posted

Yep, technically you'll never go through an engine tear down, so you can probably get away with a lot of internal mods. You can probably also set things up to dyno under 230 once a year when needed. Then again, you might get caught. You might go to a track with a dyno on site. Or you might get hooked up to a computer that reads what your PCM is doing. Or you might get hooked up to a portable dyno. Or...??? There are ways of finding out.

 

You have to ask yourself why are you going CMC. Personally, I think the shame and lack of trust from my fellow racers should I ever get caught intentionally cheating far outweighs the benefits of a few extra ponies. I've made some great friendships at the track, and I know a the fact that we're not hiding things from each other is a big driver for those friendships. You simply can't build trust when you're always sneaking around. We're here to have fun after all...and bragging that I beat you when I know deep down it was my car that beat you...well, that's just not my definition of fun.

 

Wow ... Al, you really nailed it, for me at least ... I have really struggled with this.

 

I HAVE to trust my competitors and, at some point in time, my competitors HAVE to trust me.

 

It's the "heart-felt" trust that can only come after time passes.

 

I still have this nagging feeling that I am not trusted, however I hope that changes after my competitors get to know me.

 

At first, it really bugged me ... you know, guilty until proven innicent. But then I realized I'm the new guy and have to earn that trust and respect.

 

It's all about the fun factor. Now, if just had a car to have fun in ....

Posted

Already I get the feeling that I got off on the wrong foot here. From what I am reading from the various responses is that it seems I have stepped into the realm of a potential cheater. Mind you, this was not my intent. I merely ask about the limits so the gray area is cleared for my own knowlege. I want to race legal.

 

I also want to have a trouble free car that I can take and out and really race. As the old saw goes (somewhat), you can't be truly fast until you drive it like you hate it. I want to build a rules compliant combo that I can beat the crap out of and have it still come back smiling race after race. I have the understanding that lighter weight components will result in less wear and quicker acceleration of the motor throughout it's rpm range. Some of the areas to do this are the pistons and the valvetrain. That is why I ask if certain parts are legal or not. (Ouch! My head hurts again and why is there a dent in the wall?)

 

I agree with Al and mitchntx that the trust of your fellow competitors is paramount. I hope, someday, to earn this trust. I have trust them to race fair, clean and safe and they have to trust me to do the same.

 

Another reason I am asking all these engine questions becasue I have to rebuild my current motor before I even think of running it at a track. As low as the oil pressure gets now it would probably spill it guts on the track coming out of a turn at full throttle. Not a humiliation I want to face. In light of that and since I plan on going CMC I might as well rebuild the engine accordingly.

 

 

Tony G,

 

Exactly how high do you wind your engine? When I think of high I think 7K+. Right now I don't spin my tired stocker higher than 5K.

 

 

Another question for you all. Would it be worth it to save 25-30 pounds off the nose weight but have to live with manual steering?:-?

 

 

Thanks again for all your responses,

 

Paul

Posted

Paul - from my perspective, I don't see you as a potential cheater. If anything, you are doing your "do diligence" to avoid a potential mistake later on down the road. A wise choice, if you ask me.

 

I think Mitch said it best - take a street car, dress it down, install the required safety gear, and go have fun.

 

Regarding how much we spin our engines, here's some information after one full season of racing CMC in 2004:

 

It's a stock engine - stock heads, stock induction, stock exhaust. A stock 5.0L Ford will sign off at ~5100-5200 rpm. Spinning it much past that only produces more noise, and stresses parts.

 

FWIW, the shiftlight on my 85 GT is set to 5200 - I shift @ 5400 ( the light is basically a warning, if you will ). At TWS, I will shift at 5600, only because I'm trying to mitigate the less than wonderful gearing in my car ( stock T5 ratios with 3.73 gears on an old NASCAR track with a long straighaway ).

 

The stock Ford engine ( valvetrain, shortblock ) will survive very nicely, as we stay within the stock RPM ranges. If you want an example of troublefree, Todd's car is a perfect example. All he does is change plugs and wires once every four years, whether he needs it or not.

 

I know this whole concept is hard to grasp - I had the same difficulty at first as well. But, once you compete, it will become crystal clear.

Posted

Paul,

 

I agree with your comments about building as reliable a car as possible within the limits of the rules the first time around. I understand and agree with the spirit and intent of the CMC rules or I wouldn't be building a car for the class, but in some cases I think there is short-sightedness in the rules-making process that is not in the best interests of all competitors. Just one example would be your question about an OEM crank damper. I do not understand why SFI scattershields and fuel cells are allowed, but an SFI damper is not. To say "it's not needed because somebody else didn't have a problem" is not the type of answer I would expect from a sanctioning body. If your stock balancer disintegrates and ruins your engine, I guess you needed it! The stock Mustang factory damper is a poor design for racing because it carries the weighed portion on the inertia ring instead of the hub, and problems with it are well-documented, so it is a real issue.

 

I'm not sure why a rev limiter isn't allowed, and even though I would consider it to be a safety item rather than a performance enhancer, the reality is that it won't really save you in the worst-case scenario that you miss a downshift anyway. But that is one argument for having good valvesprings!

 

In my opinion, the critical and over-arching rule on engines should be the HP and Torque limits. If you are not exceeding them, I really don't see the harm of modifications made purely for reliability.

 

I also think the factory RPM range question should be settled once and for all by the directors mandating an rpm limit of some kind, because I'm very confused by the current wording. I just had my new engine dyno'd on a Dynojet, and it's only making 223hp at 4,400 rpm and 275 lb-ft at 3,900, so I'm sure those numbers are within the range, but what if an engine makes peak power (not exceeding 230hp) at 5,500 or 6,000? Would that be legal?

 

These are just my opinions, and while I could nit-pick the rules forever, I really like the spirit of competition that exists within CMC and I'm looking forward to my first season in the OH/IN chapter. I also realize that no matter what tweaks I make to my car, the greatest performance enhancement I can ever hope to make to it is in my own ability to drive!

Posted

Thanks Adam,

 

Your are right it is so hard to believe that anything stock can survive. I have the common mindset that states if it's STOCK it MUST be BAD. I see here, that's not the case. I guess I get my rpm misconceptions from my research into Factory Stock Drag Racing where they run the stock cam 7K+ and some really steep rear gears. So then you would think that the only way to make power from a stock motor is to wind it high. Again, not the case. I can't wait to warp the minds of my gear head buddies with this info!:D

 

In your opinion, are the stock 1983 cast pistons able to survive the rigors of CMC racing? If so, this would save me some money and weight. Do you knwo of anyone who has used them? According to my source, they only weigh 470 grams each as opposed to the 580+ grams of the later stock forged slugs.

 

Thanks for your reassurance,

 

Paul

Posted

Paul - without any hard tech to back me up, I can't say for sure how well your setup will survive.

 

But, if you fall back to what was said before - stock motor, stock rpm range, stock power levels. How long does a stock 5.0L engine last?? I've seen them go 200k or more. Granted, that's for street use, but I think you understand my point.

Posted

Hey Matt,

 

I agree with you 100%. Also, why not SFI steel flywheels (NOT aluminum)? A scattersheild "should" hold the pieces of the exploding parts but do you want to risk your feet and or legs on a "should"? Just increases safety in my eyes.

 

I also see that better valvesprings will wear out less and control the valve more. Also, the production rocker arms leave something to be desired too. Ratio tolerances were probably not very high on Ford's "TO DO" list on the assembly line. Stories of varying ratios makes me cringe at power from cylinder to cylinder.

 

Like you I just want to compete and challenge myself versus a live person instead against a stopwatch or computer (video games, gotta love 'em!). It will be a few years before I can start down the road but until then I am just gonna keep on asking and learning as much as I can. When CMC gets back to Road America I can attend a race.

 

 

Thanks,

 

Paul

Posted

Paul I really don't think you got off on the wrong foot. I think I might've misleaad you some. Blame it on my dry sense of humor ...

 

Just in an attempt to let you know your thought processes are legit and not without foundation, I too was concerned about motor life. I HATE pulling and rebuilding a motor ...

 

But if you read the rules, it allows for no internal modifications to the motor. That means a stock camshaft. So, the valve train is only subjected to what the little bump sticks allow. You are probably like me still thinking big cam which translates to a short lived valve train. I just don't think it will be an issue. Noone I've talked with has had a valve train related failure. Most of these motors are 100K motors!!!!

 

It also only permits stock RPM range. So exactly where does that stock cam profile begin to taper off? Why rev it beyond that?

 

Does that help? When I began to look at the real world part of this, the things that were no-brainers in the hot rod world, but not allowed in the CMC world began to make more sense.

 

Spend your money on lubrication and cooling ...

 

For the directors ...

 

You guys need to realize that this series is growing really, really fast. A little patience and diplomacy with the newbies will curb a lot of these "debates". There is good info contained in this and other threads. But it's delivery is a little rough.

 

Just some thoughts ...

Posted
From what I am reading from the various responses is that it seems I have stepped into the realm of a potential cheater.
Nope, just a potential $$ waster.

 

Mitch - I agree that there is some shortness to the replies, but there's a reason - for most of these, there ISN'T a debate. I know the guys try to stop things before they get out of hand. But yeah, it can come off a little short sounding. Remember though, a lot of people have come in with the idea of "Okay, what mods can I do?" when there is absolutely no real need for some of them?

 

Fellas, quit spending money (or trying to), put the safety stuff in and go racing. THEN put money into where you need it.

 

This is not a class to go pushing rule limits and grey areas, you can and will be bumped!

Posted

I certainly won't disagree, Brad.

 

For those of you who have a long-standing relationship, I'm sure it's seen in the proper light.

 

For a newbie, it's rather intimidating and the anxiety level increases to ask a 2nd question ... remember my "I'll shut up now" comment?

Posted

mitchntx- Thanks for clarifying yourself.

 

bsim- I hear ya cluckin' big chicken.

 

 

Paul

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