Gavins 1st gen MX6 DSP autocross build

[gavin]

“The stock brakes on our cars suck”, “big brakes are the best way to get better performance from our cars”, etc, etc. How many times have you heard this repeated ad nauseum? Guess what?… This is absolute crap.

Its my opinion and observation that about 99.99% of the brake complaints about our cars is the direct result of crap pads, crap brake fluid, crap hardware , junk rotors and just plain substandard maintainance.

I bought the RED car with frozen rear brakes, raybestos something pads on the front and brake fluid from the paleolithic era. Didn’t stop worth a damn (Im serious about this). Id be better off opening the doors and dragging my feet. You really had to anticipate when you had to stop because it would take a long while for the car to come to a halt from speed.

“our rear brakes don’t do anything”

More crap. Replacement of the rear frozen calipers yielded a car that would now stop in an acceptable fashion. Yeah..they actually DO do something after all.

"Brake fade"…this has to be one of the better internet rumor/urban legend myths of the last decade and its taken permanent residence here on MX6.com.

I intentionally took the RED car to a track event to check this for myself. Brake fade is the result of more heat than the braking system (rotors,pads, fluid) can take. Heat has to be absorbed and released into the air before the system gets oversaturated. The heat from the rotor bleeds to the pads and then to the fluid which then boils(which is why you dont want water in the fluid) and you end up trying to slow the car by compressing water vapor instead of incompressable brake fluid.

Cooling the brake system is an easy way of reducing this possibility, venting, removal of splash shields, ducting..…. I went in the other direction on my track event, keeping the stock splash guards(or heat shields if you want to call them by another name) and using the stock monobloc wheels (which have very little ventilation). I basically made a mini brake oven that would trap as much heat as possible. I used Porterfield R4 race compound pads, ATE fluid and stock blank cheapie rotors.

I had six 20min sessions with an extra added. My instructor,s car lost a turbo manifold gasket so I offered my car to be used for his session. That had the car doing three 20min sessions back to back.

This was the result.


These were brand new pads at the beginning of that day. Oh yes, I intentionally did my worst to get them to fail. There was no fade, there was no loss of performance, there were no issues. My instructor commented on the excellent feel of the brakes and how firm they felt in his session (his normal car is a turbocharged miata, lots of suspension, race-compound tires, willwood brake kit, etc, etc)

Ive repeated this test two more times with the same result. I had a friend who had a track event but his car was in a state of disrepair and couldn’t make it. I loaned him my car so he wouldn’t miss his date. His comment about he brakes was that they were strong enough for him to outbrake a fair amount of vehicles out on track with him.

Now either my $500 car is some miracle of engineering that defies the brake fade that people say it should be having…or you’ve been fed a load of crap.

Crap pads- carbon what? Pass on the gimmicks. If it doesn’t have the same compound front AND rear, pass on it. EBCs suck, KVRs are like glazed donuts (there I said it and Ill say it again). Street pads are not autocross pads. Autocross pads are not racing pads. Street pads on a racecourse is dangerous and borderline retarded.
Crap fluid- the minimum id use for a “performance” fluid is valvoline syn-power. Its pretty decent and on every parts shelf in the northern hemisphere. Its not even expensive. Whats the excuse for less? Anything above that is a bonus.
Crap hardware- torn piston boots? Leaky calipers? Stock brake lines? Sticking slider pins?…Are you kidding me??? Replace that stuff.
Crap maintainance- fluid brown? 1mm of pad left? 19mm of rotor thickness left(minimum allowance is 20mm for those checking)? You changed the fluid in the resevoir but didn’t flush the lines? Yeah….good job.

And that’s pretty much all I have to say about that.

Next…the future of the car?

Gavin

[gavin]

THE FUTURE

While the car is in running condition, at this point I consider it to be about 80% built. There are still quite a few things to be done and even on things that have been done, there is still some “massaging” needed.

They say that you are truly never “finished” when you have a racecar. There will always be a neverending path of repair or replacement(with better/efficient components). Just as an example the newest addition to the car is a revised catch can system.




The old system worked well, very well actually. The reason for the change was that, because of the higher cornering forces of the car more oil gets forced to the cylinder head and then evacuated out to the catch cans(esp the one on the intake side). The existing catch cans were too small a volume and quickly filled. When that happened the oil was then pulled into the intake tract, intercooler and then the combustion chambers. Made a big mess. The new catch can is larger and vented to the atmosphere (so the system isn’t under constant vacuum any more). For now this is fine as the bigger question is how to keep the oil slosh under control.

Itll always be a cycle of review, renew, improve.

But before all of that, theres the rest of the 20% of the build that’s still undone. Some of it is simple, some multi-layered and complex.

The new catch can was placed in the spot where the charcoal filter was.

15.10.F. Emission control devices may be modified or removed. This permits the oil filler cap to be modified or substituted, but does not allow valve covers or cam covers to be altered to install a breather or for any other purpose.

Removing the charcoal filter was pretty simple, but removing the rest of the emissions control systems without the stock ECU going berserk will take some doing…like complete removal of the stock ECU.

15.9.A. Any ignition setting, adjustment, or system may be used, subject to the requirements of 15.10.D. This does not prohibit the use of ‘two-step’ rev limiters used when the car is stationary

Aftermarket engine control.



I will be using the Electromotive TEC3-R system. It’s a powerful and incredibly capable device which should give me that ability to really see what the F2T is capable of.

I know that some looking at this will ask the question “why not megasquirt?”. Couple reasons actually, but the main one is that Its been a long build and Im a bit tired. I have no interest in picking up another long term project that has the potential of major downtime for the car. I searched for local tuners and found a couple. Most were more focused on drag racing (which isn’t necessarily a bad thing). 034 motorsport are VW/Audi tuners primarily (they do the work on the World Challenge StaSSis Audis). They at least have a notion for turbo engines that need to have a solid flexable powerband and excellent controls at the ragged edges.

I settled with Vic Sias of Siastuning. Vic is a local autocrosser (multi nationals championship winner) who has tuned many other national championship winning autocross cars (and also does tuning on some World challenge cars as well). His specialty is Electromotive systems...this is the unit I purchased.

At this point in the build for me, (since I plan not to do this myself...today at least) I feel that its worth it to get a “box” that a local tuner is completely familiar with, hand them the keys to the car, hand over cash and then return a week later and have a perfectly running car. I want minimal downtime and an excellent tune. The system is only as good as the tuner I have been told. I believe this is true and this is the path that I took. Your mileage may vary.

On to Part2

Gavin

[gavin]

INTAKE:

15.10.C.1. Carburetors, fuel injection, and intake manifolds are unrestricted, subject to 15.10.D. Alternate throttle linkage and connections to facilitate installation of allowed induction systems are permitted, but may serve no other purpose. If an induction system item is allowed to be removed and its original mounting bracket can be removed by simply unbolting it, the bracket may be re-moved as well.

Basically any intake manifold is allowed. And with the ability to use an aftermarket ECU, I plan to create a new system for the car.






It’s a “kit” for a dual plenum sheet metal intake manifold. Along with a very short section of the stock runners and a 4.6l mustang throttle body the plan is to get a bit better flow but really reduce the weight if the very complex stock throttle body and intake design.

The dual plenum intake is a bit much for the setup I have, but it was what was being offered (the VW/Audi folks like this setup a lot) so I wasn’t too fussy about it.

EXHAUST:

Currently the car has the stock (186,000mile) exhaust system.

15.10.I Exhaust manifolds and muffler systems are free, except that they must be quiet and terminate behind the driver. Exhaust heat shields may be removed. Rear- and mid-engine cars without exhaust headers/manifold systems may use any exhaust system that meets the requirements of 3.5. This permits the removal of “heater boxes” in order to install headers on such cars.

As you can see I have a few toys that I can use (probably wont use that collector though) to fabricate a new turbo header system. It will be a semi-tubular log setup not unlike the stock manifold. Why go through all this trouble for just another log manifold? Weight, plain and simple. Oh I may get a bit better flow if I profile things right, but mainly this is a weight saving exercise.

As another nod to weight, I could make a nice equal length tubular manifold like a “ramhorn” design but, (a) I don’t really plan to be making that much horsepower (@200hp or so) so a full tubular manifold wont be of much use at those modest levels VS. a log manifold and (b) a tubular manifold means more material to get things nice and neat. More material is more weight.

Post turbo will be a simple, efficient and quiet exhaust system.

I will see about purchasing an O2 housing from Jake, from that a 3” downpipe will be fashioned, a small length of flex tubing going to a burns stainless muffler and then a simple turndown terminating behind the drivers seat.

Burns Stainless

Probably this item.

Why not a straight through exhaust? Noise. We live in a time and age (for motorsports) where noise is a very big concern. Once upon a time noise wasn’t a concern, but as development has spread, the encroachment of homes to what once was far away spaces, noise had become a big deal. For autocross, an event that rents space, the issue is huge. When/if noise complaints from homeowners happen the loss of a site is pretty imminent. Coast to coast, regions have lost sites because of noise complaints. Some regions never even knew they had run afoul with noise until told by the site owner that they were done forever.

SFR has a standing policy of 95db @100ft. It’s a known OSHA standard so its something that lawyers can understand and for competitors, its really easy to meet (95db @100ft) is pretty loud actually). We are doing our best to be good neighbors and so will I. Even though turbocharged cars are naturally quiet(er) since the turbo provides muffling, I will be using a lightweight burns muffler to reduce the noise even more. It also will allow me to meet the noise restriction at San Diegos Qualcomm Stadium which is a very tight 93db @ 50ft.


STRUTS:

Ive already alluded to this in a previous post.







The Penskes have returned from the welders and have been modified to fit the MX6)new ears and extensions to make the rears longer). I then sent them to the metal platers to get a zinc coating on them for rust protection(and added BliNg!!).





Painting and powedercoating wouldn’t work in this application because of the threaded body. Ill have to do some research on where to place the external canisters. Not sure how I can legally mount them inside the body and out of harms way. Ive seen other cars with this done, but….more research is needed.


After that things will be about 95% done. The rest will be tuning and fine tuning getting those last few %s out of the parts that I have. Nibbling away at weight (new lighter seat?, fasteners are free?). There are some folks who have gone so far as to using aluminum screws in non-critical areas of the car , or have cut down the lengths of bolts/used hollow bolts(I found out that one of my local competitors removed all washers from his car…pretty slick).

Well, that’s all I have for the time being. Its taken a bit to get here and a lot of perspiration, inspiration, money and motivation were expended to see things this far. Hope people were entertained a little by what I am doing and I hope the “whats” and “whys” have been answered adequately, if not Ill be happy to fill in the blanks.

The process never ends, but at least the car runs

To the future. Cheers.

Gavin

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