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Prepping as dedicated track car

297K views 735 replies 78 participants last post by  CanyonRider 
#1 · (Edited)
This seems to have become a popular thread and it has gotten pretty long. So for quicker access to key modifications, I figured a list of links would be nice. So here ya go:

Adding Lightness (gutting the car) starts here

Relocating battery to the trunk

Rollbar, race seats, harnesses

First track day & blown engine

Adding lightness to the hood

Solid front subframe bushings

09 Fusion motor swap

Adding mechanical gauges

Adding front tow ring

Poly bushings in front control arms; eccentric upper control arm bushings

ARP wheel studs, new wheel bearings, SPC adjustable ball joints

Side exit exhaust

Bilsteins, Eibachs, SS brake lines, adjustable rear swaybar v1.0

Brake cooling ducts

285/30 on 18x8.5 +50

Weigh-in

DIY Alignment

Adding more rear camber

Adjustable rear swaybar v2.0

Dyno Pull

2nd track report

Pedal covers

3rd track report

Speed6 brake upgrade

275/35 on 18x10 +40

Limited slip differential install

Adjustable rear swaybar v3.0

Fender Flares

Adjustable rear spring perches

Solid rear subframe bushings

Converting Bilsteins to coilovers and modified upper shock mount

Rear Subframe Swap

Setting Corner Weights and Ride Height

Track Report 4/5/14 @ VIR

SPEC Stage 2+ Hybrid Clutch

RamAir Induction

New Axles and JointShaft Bearing

New Motor Mounts

Fender Flares v2



It has been over three years since I started a thread, so I figure I’m due.

I’m not sure how other people buy cars, but when I buy a car it is with the full knowledge that one day down the road it will be a dedicated track car. So it was, when I bought the ’03 Mazda6 as a daily driver – relegating the SHO to track duty. I still remember walking into the Mazda Dealer in February of 2003 with my race helmet and asking to test drive a 6s with no sunroof so I could check the headroom.



With the exception of the occasional autocross, the 6 has been a daily driver. Well the 6’s day in the sun has finally arrived. The SHO track car is gone and the Mazda6 has been replaced as a daily driver by yet another future track car. We will now prepare the 6 for full-time flogging. Having done this before, I will share a couple lessons learned:

1. You can’t turn a pig into a race car, but you can spend a lot of money building a really fast pig. This was true with the SHO and I expect it to be true with the 6. I don’t expect to run with the Shelbys, M3s and 911s, just to be one of the fastest FWD-4Doors on the road course.

2. Before we spend money on two-piece carbon fiber rotors, double adjustable shocks, UDPs, and coilovers, we need to shed as much weight as possible – making the car less pig-like.

So here is the starting point:
2003 Mazda 6s, 5-speed, 190k Miles
Mods:
2006 engine – 70k miles
Long tube headers
CAI
Lightweight Flywheel
Kevlar clutch
Battery in trunk
Not a bad start.

Current Weight analysis – 1/4 tank of gas, no driver:
Total weight: 3160lbs
Front weight: 58.6%
Left weight: 50.5%
Cross weight: 48.9%

The total weight looks to be about a hundred pounds below the published curb weight - I attribute that to the elimination of the cast iron manifolds, pre-cats and the light flywheel. I’m surprised the left and cross weights are so close to 50% - I’m sure moving the battery from the left front to the right rear had a significant impact.

Goal – including driver:
Total weight: As little as possible - hopefully under 2500lbs
Front weight: 50%
Left weight: 50%
Cross weight: 50%

I say “Goal” as an ideal target – we will not likely achieve. FWD cars are always weight biased to the front and most of the weight we shed will be behind the front wheels. We might be able to hit the 50% L/R goal by moving some weight around. Cross weights will change as we shed lbs, but afterwards they can only be adjusted with coilovers.

Let the stripping begin! If you are in need of any interior parts (or anything else you see come off the car), shoot me a PM and I’ll get you a price. I plan to sell or Ebay as much as I can to fund my habit.




Here’s what is coming out:
Trunk liners
Seats
Console
Carpet & pad
Headliner
Trim
Radio
Speakers
Dash
Airbags
Door panels
Window motors
Glass (except windshield)
Trunk lid reinforcing (keep the skin)
Trunk hinges
Rear doors and hinges (except skins)
Exhaust (behind headers)
Sound deadening
Heat shields
A/C compressor, evaporator, accumulator
Bumper bars (keep bumper covers)
Hood reinforcing
Front fender reinforcing

After it is striped, we’ll weigh again before adding the roll cage, fire suppression, transponder, race seats, harnesses, etc.

I’ll post pics along the way for your viewing pleasure.

 
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#598 ·
Speed6 reference, since it's an AWD platform, and it might be easier to go that route, along with the benefits of AWD as well to go along with the extra power.
 
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#599 · (Edited)
Got it, thanks. That would be much easier, and I guess that would be very robust at the 235 hp target from CR, with big torque numbes. But if he's looking at a V8, I'm not sure the MS6 with transfer case heat-up and possible rearend issues would be a strong as his RWD concept. I know that there are versions of the coupling and control module that are more highly developed, and migh be possible if he wanted more rwd effect.

EDIT: The MS6 is also limited in body roll control by the RSB with a verical ~8" offset in the normally straight length between bushings. This limits the rear WL upgrade to about 2mm above the 24mm oem dia, which in turn does not allow a front bar upgrade, to avoid excess understeer.

And, CR has had a taste of RWD on the track in the 580SE, and he likes it.

.
 
#602 ·
.

And, CR has had a taste of RWD on the track in the 580SX, and he likes it.

.
True dat!!!

Besides, we all learned from an early age:





:grin2:


CR
 
#601 · (Edited)
Not to threadjack but I broke down and bought the pump lock ring tool a couple of years back after the plastic ribs on the lock ring started sheering off on my '93 Altima. Same style lock ring and the tool uses a 3/8 ratchet and is adjustable. About $20 through Amazon or Advance Auto Parts.
Lock Technology Gas Tank Fuel Pump Removal Tool LTI940: Advance Auto Parts

Awesome project with the 3.0 CR!
 
#604 ·
Back to our fuel tank problem

When last in the garage we had the fuel tank out. Here's the filthy tank - we cover the opening with blue tape and clean the outside.





Although the outside is clean, the inside still has dirt and fuel in it.



We quickly realize that due to the shape of the tank and the location of the openings, there is no way to rinse and dump the tank out. No matter how you turn it, you can't completely empty it. So . . . . we drill a hole in it. :surprise:



Now we can rinse and drain completely. Clean tank - inside and out!



We use a drain plug kit intended for transmissions:



and plug the hole. Now we can drain the tank anytime we want.



Drop the new fuel pump in - man is that thing white!



Recall what started this mess was the tire rubbing on the filler tube:



I'm waiting on parts to finish putting it all back together. Stay tuned! :wink2:
 
#605 ·
Wow! Where has the summer gone? We've done 4 races in the team car - including a 24hr last weekend. Rode the motorcycle for 2 weeks in NM, but haven't driven the Mazda since April at VIR. Also been cleaning up the garage - hung some cabinets that I scored from someone else's renovation project:





Time to get the Mazda back on track - literally! Here's the schedule for the rest of the year:


9/12-13 Virginia International Raceway in the Mazda
9/19-20 Carolina Motorsports Park in the team car
10/3-4 North Carolina Autocross Championship in the Mazda
10/17-18 Carolina Motorsports Park in the Mazda
12/5-6 Virginia International Raceway in team car


I have a few things to do to get the Mazda ready for VIR - I'll be posting some prep work as we go. Get out there and race those Mazda6's!
CR
 
#606 ·
Last night, I finally got my Canbus Speed Limiter hack working. I have a little cleanup of the wiring to do then I'll post details. No more cutting off at 120mph!!


Here's the list I'm working on in prep for VIR on 9/12:
Back off the camber from -2.5 to -1.5 - With my stiffer springs and swaybars, I found there is so little body roll that I don't need that much static camber. In fact, I'm not getting full use of the tire.
Speed Limiter Hack - Almost done!
Trim rear inner fenders a bit more for tire clearance - Getting just a very small amount of rub.
Revise camera mount - Done
Weld new tiedown hooks on rear frame rails - I moved the tiedowns in the trailer to allow the car to sit further back.
Change oil
Flush brakes


CR
 
#611 ·
Back off the camber from -2.5 to -1.5 - With my stiffer springs and swaybars, I found there is so little body roll that I don't need that much static camber. In fact, I'm not getting full use of the tire.

I think your car is currently more stiffly sprung than mine, but I've found the same. Two years ago with stockish suspension I was around -2.3°, then found I could be around -2° with the new spring setup (roughly triple spring stiffness front and rear). Went to poly LCA bushings (the last ones I changed) and had to pull out even more. I need to get it on a rack to see where it actually ended up, but probably somewhere around -1.7° to -1.8°. Makes for some great braking.

I've been working with accelerometer data in my MS6 to improve my driving and to assess setup changes. Even on street tires, this chassis has some good potential!
 
#607 ·
Oh yeah, I forgot to mention I have to replace the right CV axle. I know you're thinking (because you are an astute reader of this thread) Wait a minute CR. Didn't you just change BOTH axles less than a year ago - about 5 pages back on this thread? Shouldn't axles last longer than brakes and tires?? Why yes. You are correct, sir! Recall my track report back in April, I mentioned the serp belt broke - well I didn't notice it at the track, but the belt cut the CV boot.

Notice in the pic how the belt is right in line with the cut boot.


Got the old one out and ordered a new one:


Now I got a mess of grease to clean up. GRRRR!

CR
 
#608 ·
I'd go with aftermarket axles with LLT warranty= free replacement, but not sure how they would hold up on the track...Lol
 
#609 ·
Speed Limiter Hack

So harken back to last spring when we were talking about defeating the speed limiter:

Speed Limiter Discussion

I have finally gotten around to actually doing it.

DISCLAIMER: This is shared for entertainment purposes only. I do not advise you to modify these systems. I am not responsible for you burning up control modules, making your car unusable or you crashing your car and dying.

Here's what I did - keeping in mind that my intuition nearly makes up for my poor judgement. :grin2:

I unplugged the 28-pin connector to the ABS controller.


I stripped back the harness covering so I could get to the wiring:


After much testing and analysis, I determined there is one wire that when interrupted, the car will continue to accelerate past 120mph. Here is the pin and the wire with blue tape:



I cut the wire and extend the two ends into the drivers compartment:



I ran the wires thru a normally closed pushbutton mounted on the dead pedal:



Re-install the dead pedal in the car:


How it works:
As I approach 100mph, I step on the pushbutton (breaking the circuit to the ABS).
The speedometer drops to zero, the ABS and TCS lights come on.
The car continues to accelerate past 120mph.
As I lift from the throttle, I also release the pushbutton.
The speedo snaps back to life and the ABS/TCS lights go out.

Issues/Risks/Problems/Reasons not to do this:
The wire I found may not be the same for other years and generations.
While the pushbutton is depressed, you have no ABS, EBD or TCS. The big issue is EBD - Electronic Brakeforce Distribution. If you apply the brakes with the PB depressed, you will get equal brake pressure sent to each wheel - locking up the rear wheels sending the car into a spin (ask me how I know).
If something cuts the wires you ran to the PB you will have no ABS, EBD or TCS.
When you release the PB, the TCS is enabled. This is not helpful on the track if you prefer to run with TCS off as I do. You have to reach down (at race speed) and shut it off again. I'm gonna have to figure out how to fix this.

Thats it! Wadaya think??

CR
 
#612 ·
Yeah I'm anxious to see if I get increased grip - we'll find out on the 12th!


Just for reference here are spring rates I have run over the years:


OEM M6s - 220f/150r
Eibach Pros - 250f/200r
Race springs - 700f/500r


Huge difference when I jumped to linear race springs. Its a stiff ride, but you can really lower the car and the grip is awesome.


CR
 
#614 ·
Holy crap! Next event is on VIR Grand West course:

http://virnow.com/files/2014/03/GrandCourseMap2014.jpg

OMG it looks like awesome sauce! I've never driven this course. I better get the Mazda out of the trailer and into the garage - need to be ready for late February! Stay tuned!!

CR
 
#616 ·
Wow that looks like a fun four miles!
 
#618 ·
I've heard people talk about T13 - 110mph entry, hard right, down hill, off camber . . . its called "The Bitch"

Can't wait!
CR
 
#620 ·
Yeah, I have to work up my speed on the uphill esses every time. Takes courage to run them as fast as the car is capable. Back in september, a Cayman R went into the tires there. I spun at the top several years ago. Fun, but unforgiving. :)
 
#622 ·
Back to work on the Beast!

The 2016 season is coming and there is work to do.

Back in Sept we broke the right axle at VIR.
We have a worsening engine oil leak.
We need a windshield defroster if we're gonna run VIR in February.
Need to decide what to do about our ABS speed limiter hack.

Here's our broken axle - pretty sure there are supposed to be some balls in there.


Here you can see the alternator and everything above it is wet with oil.



It looks like a combination of several leaks - the valve cover gasket, the OCV seal and the OCV housing itself is leaking. I've ordered all the parts.




Waitin on parts.

CR
 
#625 ·
Napa #NOS-10930

Not OEM, but the dimensions a VERY close. I'll let you know how it goes.

CR
 
#627 ·
OK got some parts! Got the valve cover off. Here's the right valve cover. You can see the OCV seal is in pretty rough shape - in fact part of it is still on the OCV.



Here's the old seal on the right, the new seal on the left and the Napa part number on the box.



The rubber seal fits very nicely on the OCV. The shell of the seal is not quite as tight in the valve cover as the OEM seal. You still have to tap it in but it doesn't require much force. I added a VERY SMALL amount of RTV in the valve cover where the seal sits. This will provide a little more sealing peace of mind.



Then tap the seal in with a socket that matches the shell.



Flip it over and notice a bit of the RTV squeezed out. Clean it up and don't get any on the rubber seal.





Ready to put it back together.

CR
 
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