Are you new to autocross? Since you don't know the class rules I'm guessing yes.

Do nothing to the car. Learn to drive and learn the car at the same time.

For your first half dozen events or so just waste the tires the car came with. No sense spending good money on tires that as a newbie driver you are going to feather to hell and back anyway.

Make sure you do lots of ride alongs and get lots of experienced drivers to ride with you.

Then, get some decent street tires on the same wheels.

After a season on decent tires think about some cheaters.

The following season maybe do some suspension tuning with sway bars (only!).

Then, maybe, do some HDPE/lapping on the same setup.

Following season think about Rs and serious suspension mods. Then you'll know what your driving style is and how to make the car drive that way without asking a lot of questions that you should already know the answer to.

It's not a very sexy way to mod your car and buy it presents but you'll know how to drive at the end of it.

2¢

 

Is that what you get out of my questions? I guess I need to work on my wording. Thank you for your 2¢.

I have read over the rules several times (however they are obviously not mustang specific.) The specifics I have googled. The answers I can/could not specifically find, I posted/will continue to post here.

Am I new to Autocross? no. But I am also not a seasoned pro. I came from an AWD Audi A4... Ran in SM, usually somewhere in the middle of the local pack of EVOs and STIs. (Local being PA, I'm new to the DFW area) With a different chassis comes different tricks for getting it to turn. This particular chassis was used for many years and equipped numerous different ways. The whole forward dating/back dating and trim level part swapping ability is throwing me for a loop right now. With the Audi, it was not really an option. If I asked you for the recipe for a competitive A4, you could probably give me a few general rules of thumb, but I doubt you could answer some of the finer questions to making it work. Does that mean you too are new to autox and don't know the rules? Hardly. (Though it could, so I understand your reasoning)

Am I new to Fox Bodies? No. I've owned at least one of them for the last 14yrs.

Am I new to autocrossing a Mustang? Yes. In the past, the only "line" I cared about was a straight one. This is a different take on an old friend.

Right now it is winter time, so about the only thing I can really do is ponder and plan. What I do know is going out there 100% stock is not even an option I'd be interested in. Stock the steering response is lazy, the is chassis relatively unpredictable and many other not good things... As Cobra4683 pointed out, the rear end in stock form is also a sad example for any kind of cornering. At the very least I'd want to replace all the front bushings with poly, rid it of the steering rag joint, do something about the rear CAs, and rebuild the T-Lok. That would at least get me a chassis that is somewhat predictable (though it still may not handle well) From there I could consider beginning to take your advise and moving forward. But that advise itself brings up several questions...
Do you waste money upgrading the stock 4-link with a PHB and/or new control arms only to remove it for something better in a year or 2 due to wanting something that performs better or because the class you want to run in requires it? Or do you pick your class first, then mod towards that goal? To me, the latter seems like the better idea. The purpose of this thread is to help me nail down the smaller details.

Cobra4683 (Thank you too for the reply BTW)...
Speaking of the wobble/shimmy, upgrading the RCAs does wonders for fixing that. My notch has a Detroit Locker in back that used to severely magnify that feeling with any turn (even a simple hwy lane change). I put a set of MM extreme lowers on there and it all but eliminated that problem. I'm sure you already have, but if you have not yet upgraded yours, it's something I'd highly recommend.

 

I would add a mm pan hardbar too. The ass end of the fox can feel like it's got the wobbles. My rearend deflected so much it rubbed.

 

I haven't gone to Nationals or raced in ESP in almost 20 years in my fox and there's a reason for that; the SCCA SP rules were a joke. My advice is find a club that doesn't use SCCA rules; a fox is never going to be competitive, imo, in Texas going up against Madarash, S197s, etc.

Now, CP, otoh, is another story but I don't know how cheap you could make a competitive CP car.

HOWEVER, I don't keep up with any SCCA results so all I know is what I hear via my friends in Texas who auto-x (Terry Fair at Vorshlag, Kent Kroll, etc.).

Anyhow, I did a ton of research on this issue back in the day. I even have, afaik, the only copy of Ford's 1993 near-final-draft mustang spec sheet (the thing they have to give the government). I sent a copy to Kent Kroll, a regular Texas auto-xer in ESP. Anyhow, I should still have that thing around somewhere. Maybe I'll get off my ass and scan that thing. It shows all the part #s and notations for odd things like the 93 Cobra R's rear seat delete, etc. I've never seen another copy nor heard of anyone else having one (although I'd be surprised if Jack at MM didn't have a copy of the final draft).

I don't think you need to spend 5 years getting to know a car/learning to drive. Year 1, auto-cross on ####ty tires (buy caster/camber plates and get an alignment, -2.5* camber, as much caster as you can give it, a pinch of toe out, imo). GO TO AS MANY EVENTS AS YOU CAN. Dallas, Austin, Houston, College Station. Texas has a ton of sites with active clubs. You will learn a lot.

Year 2, buy cheap, long-lasting R compounds and start doing basic suspension mods. If you can't go PM3L or front-coil overs, skip right to CP because a foxbody sucks until you do both the front coil-overs and fix the rear, somehow.

Year 3, throw money at the car if in CP. If still in ESP, sell car, buy a real car and go race in a stock class.

Again, I am not looking at the SCCA rulebook but to answer your questions:
Intake and up is free (so yes, everything above the heads that moves air can be changed). I wouldn't waste money on this stuff though until you have heads.
Heads: have to be GT40s, not GT40P, with stock valve bits (which blow).

IIRC, the 93 Cobra cam was a thunderbird cam that you can't get new anymore. I always forget this bit. Some people say there was a TSB that swapped it to an e-cam. I don't think there was. Anyhow, even if you put a cam in it no one is going to give a #### because you aren't going to be winning the class. Everyone switched to 3rd gen F-bodies in the mid-90s for a reason. Then to 4th gens. Everyone except Madarash because he has the golden combination of a car that never really existed (heh) and tons and tons of development and seat time in that car.

Re: rears, you mentioned a budget, I'd go PM3L.

You haven't even mentioned wheels, brakes, weight, etc. The brakes suck. Old members of the Texas A&M Sports Car Club have videos, somewhere, from the '90s of a 60-0mph braking test in which a foxbody loses to a 1/2 ton truck. They suck that bad.

Re: weight, take it all out, the 93R was stripped. I removed my sound deadening carpet (75 pounds) and tar (75 pounds) from my notchback. The stock seats weigh ~45 pounds each, look for 2 used aluminum racing seats on corner-carvers or save up.

Re: wheels, you can barely fit 9s up front, everyone else is probably running 11s or 12s by now. I remember when 255s seemed like a huge ass tire. Now I'm trying to figure out how to run 305s on the front of my car.

Pick up a copy of Mathis's Mustang Handbooks. Yes, some of the data is old (and apparently his editors ####ed up some of it and left some of it out), but it's your entry level bible into what needs to be fixed.

Go read every corner carvers foxbody/auto-x thread that you can find.

Seriously, save yourself the hassle, buy a BMW or used Corvette or a Miata. Hell, I'd take a 3rd gen, throw some big ass wheels on it (because they fit!) and go have some fun before I re-did my mustang.

 

Now, CP, otoh, is another story but I don't know how cheap you could make a competitive CP car.
.

CP = "Cost Prohibitive". LOL.

 

Old School, if you are going to stick with a Fox, ESP or Street Mod are the ways to go, and it can be fun on a budget, but I would not expect a championship caliber car.

And yes, in ESP both the intake and exhaust are completely open with the only restriction of a maximum sound level requirement.

Both of these classes allow any DOT tire on any size wheel. Both allow most subframe connectors.

The things that will matter in ESP are rear lower links, torque arm and a Watts or very well placed (adjustable length and pickup height) panhard bar. I prefer the Watts. A good adjustable front swaybar, fairly stiff front spring rates with moderately stiff rear rates and decent shocks that can support the spring rates you choose. You'll also want a good limited slip diff.

Street Mod allows a lot more. You can swap arms, spindles, engines, transmissions, entire rear axles and more. That class is a lot more tolerant of some of the small suspension and drivetrain mods that we think are standard procedure for a performance car.

 

This was written several years ago by someone on c-c.com and I'd updated it a couple of times since then but be warned, some of the info is out of date (ie suppliers don't exist anymore, prices are wrong and so on). It's still a decent primer on what can be done to an old fox.

PlasticSpoon

My own Fox has a mix of DIY and vendor parts and is woefully uncompetitive locally in CP. I don't really care (I've got enough cheap trophies collecting dust as it is), I just like going out with what I've got and enjoying myself.

 

Eh, it depends on how far the rabbit hole the OP wants to go. CC plates and some bars 'n springs will reduce the front tire pain to a dull ache. He still won't be competitive but will be less frustrated with the car.

 

Stuff like this is hopeful info. Maybe even with a pm3l or 5-Link thrown in the mix too.

The gear restrictions and iron heads are the hardest pills for me to swallow. The rest I think I could live with.

.....

Mainly street, but with track outings. HPDEs are something I'd like to eventually get into also. Another reason for a potential class change.

Thanks for the CAM info. Looks like it will be a fun class to watch.

1993 Cobra parts ... knock yourself out!

Excellent! Thanks.

Agree with the CP build. I started out looking at ESP but found the restrictions way too compromising for a sometime A/X most of the time DD. As a result, I went PM3L w/MM PHB for a couple of seasons - maybe three - can't recall. That one mod transformed the rear, but it has it's quirks. Got to get the rear spring rate correct for optimal performance.

Two seasons back I went T/A and adjustable height LCAs, and the MM K. Car is much more fun but has to play in CP.

Several of you bring up the pm3l... And if I was looking at an eventual class jump, I guess it makes more sense. Researching it, there seems to be some durability issues, cars killing torque boxes, bushings, etc. Is that something to be concerned with or do I just factor in a battle box and an annual bushing swap?

Are you willing to elaborate any on getting the spring rate correct and what worked for you?

Thanks guys.

 

1993 Cobra parts ... knock yourself out!



Accessory Drive Parts

F3ZZ-8509-A Cobra Water pump pulley
F3ZZ-6A312-A Crankshaft pulley
F3ZZ-8620-A Accessory drive belt



Cylinder Head Related Parts

F3ZE-6250-A Cam
E6AZ-6582-B Rocker cover, left
F1SZ-6582-A Rocker cover, right
F3ZZ-6049-A Cylinder heads, bare up to 4/13/93 (1)
F4ZZ-6049-A Cylinder heads, bare after 4/13/93
F3ZZ-6049-B Cylinder heads, w/valves up to 4/13/93(1)
F4ZZ-6049-B Cylinder heads, w/valves after 4/13/93
F3ZZ-6026-A Plug, core sand cleanout
F3ZZ-6507-A Valve, intake
F3ZZ-6505-B Valve, exhaust
F3ZZ-6513-A Spring, intake valve
F3ZZ-6513-B Spring, exhaust valve
F3ZZ-6A536-A Retainer, valve spring
F3ZZ-6079-D Gasket set, valve grinding
F3ZZ-6564-A Rocker arm
F3ZZ-6A585-A Fulcrum, rocker arm pedestal
F3ZZ-6A527-A Bolt, rocker arm attaching
1. includes date specified

EFI System Parts

F3ZZ-12A650- CA Computer
F1SZ-12B579-A Sensor, Mass Airflow
F3ZZ-9E926-B Throttle Body
F3ZZ-9E433-A Gasket, throttle body to EGR plate
F1TZ-9F593-C Fuel injector

 

I only have a few events with a PM3L in my notchback. Front springs were 425 coil overs, rears were 350-390 conventionals. At my last event, I was apparently picking up the front tires massively coming out of turns. The car felt mega grippy on old ass road racing tires but obviously I couldn't turn under power. After much debate, I've decided to step the fronts down to 375s and the rears up to 415-515 rears. This will narrow the wheel rate gap considerably front to rear and should, theoretically help the car turn while preventing it front picking up the front tires. I'm not too worried about the torque boxes or bushings since I went with a rod-ended spherical-bushed setup.

qttracer has much more experience with this setup.

 

To the OP, I currently run CP at the local events. The DC region is one of the largest in the country yet the CP class rarely sees more than 4 cars. ESP on the other hand, sees as many as 20. With the new CAM class, the Fox chassis may do pretty well since everything that is generally limited in ESP and CP is open. Some of the mustang guys have gone to the ST classes too. But if the point of this is to just have fun, mod the car as you choose and change classes as necessary. Not many challenges to "minor" violations.

 

So, revisiting this idea again...

Still looking at ESP for now. In the SCCA Rule Book, section 15.6 - Brakes for ESP.

It appears as though most standard upgrades are legal so long as they are larger than what was there before? Am I interpreting the rules correctly?

I'm wanting to convert to 5-lug for obvious reasons and wonder if it matters how I do it... I'm considering the usual suspects... sn95 Cobra, sn95 GT or Lincoln/Ranger.

Would any of those options NOT be legal in whole or part? if so, why?

 

For ESP in a Fox chassis, update/backdate rules apply to a car on the same line in the appendix for ESP (generally all Fox chassis cars). This means you can use the SVO, 93 Cobra or 93 Cobra R brakes. Pick one - can't mix and match. With any of these means that the rear track will be about .75" wider per side than the standard Fox chassis.

The SVO brakes are not recommended unless you need a stock class car. The 93 Cobra is 4-lug. If 5-lug is the goal, then the 93 R. The problem with the R brakes is the controversy surrounding the configuration. While the front brakes are typical sn95 Cobra, the rears are the issues. Some say the rears are identical to the sn95 Cobra (i.e., 38mm caliper; 11.65" rotor). Others say the rear is sort of a hybrid using the 93 Lincoln Marc rears which uses the same caliper as the Turbo Coupe (45mm), but a 10.5" vented rotor. I used the T/C rears (45mm caliper; 10.25" vented rotor) on Fox length axles spaced out .5" per side with the sn95 Cobra fronts. A few looked it over but a quick glance would not have given it away. In any event, no one really cared because the car was never in the hunt.

 

Thanks for the reply. I was afraid that was the case. I was hoping the information I read was just outdated. I saw a thread where Jack H. mentioned the SN95 GT rears (10.5" solids) might slide as a stand in for 93R rears as well.

I'm really just looking for a spot where the car could be half way competitive with out going hog wild on mods, I guess its just really not possible.

This is slowly crushing my spirit. LOL

 

Foxbodies haven't been competitive in FS since the early 90s. Really, back then, anyone with a clue in a 3rd gen camaro could kick the mustangs' asses. Same is true in ESP. The only place in SCCA Solo II where they are still somewhat competitive is CP because you can do crazy stuff in CP that levels the playing field with the other big iron cars.

 

You have told me that several times, and as much as i don't want to believe it, its slowly sinking in.

My beloved fox is just old. *sniffle*

LOL

 

You know where the fox is really best placed these days? NASA's CMC class. But that's a whole different level of $$. Still, if your long term goal is HPDE/road racing, I'd build towards that and then auto-x in ESP, or in some catchall class, in the meantime for fun.

 

I had a 90 5 spd that I autocrossed

I had a 90 autocross set up mustang with 4.10 gears and the stock long block. I had a tune and a solid brand new motor (rebuilt of course) I raced it with the bbk subframes a couple times with the bbk springs and bilsteins with a panhard bar and upper stru tower brace. Then I upgraded to the MM full length, then the toque arm, adjustanble rear swaybar on level 2 MM lower control arms and an alighnment with Porterfield brake pads. Seriously it felt like a different car (in agood way) I ran the same tires everysingle time 245.45.16 on the ponys. The grip and agileness was SO MASSIVELY better. I could floor it so much more from a slow speed and not worry about traction, while with the previous setup I did. I also ran on a full tank of gas with those gears. I had the battery in the back too. car weighed appr 3400 with me in it in this form. I would recommend TIRES, TIRES, and TIRES if you want to get maximum traction, assuming you have decent driving skills. In high horsepower cars I don't take t the strip without slicks/drag radials and expect it to perform. I learned the hardway it is kind of the same concept just a different race. ANy other things I can help you with you can pm me

 

Yeah since intentionally built my car for autocrossing and spent much time and research on this project as I am a blue collar worker, I wouldn't build a stang or a 5.0 for this typer of racing. I would rather purchase a Miata and rims/tires and I would be WAY faster. The stang is fun but expensive to make handle well in this event.

 

Yea, I think I am just going to take aurdraco's (and most everyone's) advise and mod it as I see fit, leaning towards HPDE events, and just dump it in whatever Auto-x class it currently falls under along the way... beginning at the bottom with a stock motor & stock suspension complete with original shocks and 26yr old stock bushings. The suspension really needs about a grand thrown at it just to make basic cruiser status. (maybe ill do that much and just stop there)

LOL - In the words of Po, "Lets just start at zero, level zero."

Kung Fu Panda(2008) - Level 0 - YouTube

 

That's where I started. I would recommend the bushings if you can or plan to keep the car for a while. I started out there also 225/55 tires etc and experienced the transformation. One grand I would buy subframes even the bbk least expensive ones (as I had thos and they work) I wouldn't do the MM ones if you aren't going to change to all the MM stuff. purchases springs and shocks/struts from MM. This will be huge and get an alignment. These subframes work!! Then get tires. Lower the car about an inch or so will help

 

You may desire to speak to others about the MM subframes. However in (imho) without the torue arm etc from MM they might be too much weight. I remember them waying much more than my bbk's granted the MM were full length while the bbk aren't. If you live near a supplier that sales both of them ask them to see them before you buy them. Bring a scale...I took off the bbk then put on the MM full lengths drove around and even autocrossed it befor eadding the other MM stuff. I didn't notice a difference with just the subframe change. however, once I added the othe MM stuff, wow, I mean wow, we are talking traction and agileness. a different car. My brother has a stock motor 87 fox with springs, lower control arms and shocks. My car BLEW his out of the water. The stiffness of my chassis compared to the stock car, WOW, I can't even drive his it flexes so much. he doesn't even have subframes, subframes make a big difference

 

I'm glad this information is out there. I want to get started in autocrossing and roadracing on a budget. I'm turning 40 in 2016 and I'm going through a bit of a mid life crisis...lol.

 

chump car

 

I'm probably going to start with a SN95.

 

These have advantages and disadvantages when comparing to the Fox chassis. The biggest negative is weight. And IMHO, the chassis isn't as nimble. But if you are doing a purpose built car, in A/X consider CAM.

 

I will agree that the S197 chassis is a better starting point compared to modifying a Fox or SN95 nowadays. Terry's built up started off not too ridiculous but he eventually completely lost my interest by the time of the rear wing and front splitter.

His wife's grocery-getter indeed...