Lemons probe / engine rebuild/ other hack job work

[rmlunsford]

Never started a decent thread here, and I doubt this will be one but it's an attempt. My dad and I got into 24 hours of lemons / chump racing about 6 years ago in a strange set of events involving a crazy alcoholic friend of mine and another buddy who worked a scrap yard and a 90s 7 series BMW automatic. We showed up thinking it was going to be people racing actual $500 cars, to the extent that instead of replacing tie rod ends we poured melted lead into them to tighten them up. We broke an engine mount in that first race and jacked the engine up and stuck a 2x4 across the frame to hold it in place. This threw off the angle of the drive shaft, ultimately catapulting it into the drivers leg (no real injury just a bruise). That car got scrapped and we bought a first generation MR2, which was fun but has a 10 gallon fuel tank. In 2012 we bought our probe, which has been a lot of fun.

https://scontent-dfw1-1.xx.fbcdn.net...1a&oe=56EA8FBF

We are probably the worst group of mechanics ever to attempt an automobile race, so the endeavor has been without any form of victory beyond the time we only brought one set of tires and we raced so long they burned up and we had to put the car on jack stands and drive into town with the rims to get a new set of tires put on. On a Sunday in Texas, which means someone had to leave church to come help us.

All that said, we're finally maybe getting closer to an actually decent car. We took the probe to Barber in February of 2015 and after about 2 hours of racing we had a huge billow of black smoke come out of the exhaust and found a ton of oil in the intake in the pit. We cried a little and decided to trailer it home with pretty poor compression. I finally got around to pulling the engine apart.

Gonna figure out how to imbed pictures and then i'll keep it goin.

Ok still can't figure out how to embed photos but i'll get that squared away. Have lots of pictures of an engine in pieces and a burnt up piston. You'll see them later.

So to list the failures we have had with the probe thus far: 1) We raced at Texas Motor Speedway, which is a NASCAR track. I can't believe they let us on there, but the layout was a full oval and the into the infield. Needless to say this annihilated our brakes. So bad that at one point while i was driving the pedal just hit the floor and I was lucky to only smash through cones instead of a wall. We upgraded the brakes and vented them pretty well and haven't had a problem since.
We had a wheel bearing give way and the entire front right spindle sheer off, the wheel was hanging on by brake lines. That was fun. I'll add more failures as I think of them, we've had plenty.

Plans going forward: We found a set of JIC Magic (maybe the right name) coilovers for a protege? here on probetalk. They aren't installed yet but they look sick and I'm sure the spring rate on the front is super wrong. The are massively cheating but they were a great deal and ultimately less than buying new shocks so whatever. We ordered a big 2 core Howe Racing radiator and a low temp thermostat and we're in the process of rebuilding our "ZE", who knows if its actually a ZE.

Alright so the engine is in pieces. http://i411.photobucket.com/albums/p...pskoaefjmu.jpg
Appears that the numero 1 piston burnt: http://i411.photobucket.com/albums/p...psdtzkpxjb.jpg which is why we had so much blow by / bad compression. The piston scored the cylinder wall decently: http://i411.photobucket.com/albums/p...psrk4jalnj.jpg



[To be continued]

[yellowrob]

Sounds like you guys got some work to do.

Stick with the probes so the knowledge stays one tracked.

[dillinr]

Oh I like this thread already.

[yellowrob]

Oh I like this thread already.

You were reading my mind.


Subscribed

---------- Post added at 01:57 AM ---------- Previous post was at 01:54 AM ----------

Never started a decent thread here, and I doubt this will be one but it's an attempt.

You're wrong..... keep us fed.

[RacerXR]

I race a '93 626 in LeMons, Chump, and WRL here in Texas. I'm running the 2.0L motor, so I can't give you much advice regarding motor setup. But, I can give you some pointers on brakes, suspension, and wheels/tires. The 626 has the same guts (motor, trans, suspension, brakes, etc) as the Probe.

One thing I do know about endurance racing the 2.5L motor is bring spare head gaskets to every race. If you are replacing the head gaskets, I highly suggest getting the heads straightened/shaved, the block decked, and installing ARP head studs.

BTW, if you need a fresh '94 Probe chassis, I got a very nice one you can have for free. You just need to come pick it up here in the Dallas area. I'm keeping the motor, trans, suspension, wheels, and brakes. So all you would get is a chassis and few other parts. Here's a link to a pic of the chassis on my team's facebook page. Let me know if you are interested.

https://www.facebook.com/JoBoRacing/.../?l=c6423d4a91

I was gonna cage it myself. But, I got laid off last year and don't have the funds to build another car.

[RacerXR]

Here's a brain dump of my suspension and brake lessons learned from racing a '93 626 the past 4 years. All of this should apply to the '93-'97 Probe. BTW, My 626 has the same wheelbase as my Probe and according to factory specs it weighed 18 lbs less then my Probe from the factory. Stripped and caged, they are basically the same chassis.

• The MazdaSpeed 6 front brakes are a bolt on upgrade. They provide excellent modulation, more than enough stopping power, and they work well with the factory master cylinder. You'll have to buy the Speed 6 calipers w/brackets and rotors. They'll bolt up to your existing hardware, including the flex lines. I believe this setup requires 17" wheel.
• Supposedly the Speed 6 rear brakes are a bolt on upgrade as well. I haven't tried them. Instead, I upgraded to '98+ rear rotors, calipers, and brackets. The rotors are slightly larger diameter than the '93 - '97 rotors. It makes a slight difference and matches relatively well to the Speed 6 monster rotors up front.
• The '05 - '06 (I forget exactly which years) Mazda 6 standard front rotors and calipers are also a very good upgrade. They are easier to find and much cheaper. The Speed 6 rotors are almost too big and provide a lot of initial bite. This makes them easy to lock up if you stab the brakes. The standard 6 rotors would be a little better in this instance. Check brake pad availability and price before you select the standard 6 or Speed 6 upgrade. A team up in Canada is running a V6 626 with this setup. They seem happy with it. But, they have limited track time on it so far. See the links I provide at the end.
• I've removed the brake dust shields and gutted the front inner fender so air can flow from the fog light holes in the bumper cover to the back of the rear brakes. Since doing this, brake pad life increased noticeably.
• I run Motul 600 brake fluid exclusively and replace it every couple of races (or twice a year). I have never had any problems boiling the brake fluid.
• I run 45mm offset 17x7 Konig Zero-In wheels. They are cheap, light, and ugly. I've bent a couple and replaced them.
• Talking tire selection is like talking religion. But, I'll share my opinion here. I run 215/45-17 Dunlop Direzza Z2's. They communicate very well, you can't overheat them, and they wear well. I've tried the older BF Goodrich Rivals, they were just as good. But the new model wears out way too fast. I've also tried the Falken Azenis RT615Ks. They wear well. But, you can get them hot and greasy pretty easily. Backing off for a lap or two will bring them back. But, why bother when the Direzza's perform just as well and never get greasy.
• Brake pad selection is another religious topic. In my opinion, Carbotech brakes suck. On my car and several other teams' cars, they developed a very bad shutter and completely failed in less then one race. I will never buy Carbotech again. I run Hawk pads exclusively. I've seen the pic of your car on the WRL page. So, I assume you have run with them. If so, they are sponsored by Hawk and as a WRL participant you can get a great discount on Hawk brakes. I run the DTC-60 pads on the front. They provide reasonable friction without too much initial bite. They modulate and wear very well. I get 3-4 races out of one set. Too negate the need for an adjustable brake bias valve, I run Hawk HP plus pads on the rear. They have amazing initial bite and friction. This improves the rear braking and balances the car better.
• The front factory sway bar is plenty stiff. No need to touch it. Replace the end links if worn. I haven't even bothered replacing the original factory bushings.
• I upgraded to King6 endlinks front and rear. They're just a handful of heim joints, threaded spacers, nuts, and bolts. You can source the parts directly from McMaster Carr or other industrial supply house. But, it won't save you much. Either way, it's cheap and you might as well if you are replacing worn out links. It's highly likely that the end links that came on the car are worn out.
• The rear sway bar from a '98+ 626 is 5mm thicker (17mm) than the '93 - '97 sway bar. It's a very good upgrade. The best $35 dollars I have ever spent on a car. I am currently running a AWR 17.5mm sway bar. I got it with the Probe. It's ok, but not worth spending money on it. If you are racing LeMons or Chump, a junkyard '98+ sway bar will draw no attention from the judges.

[RacerXR]

• I've run poly bushings and cheap OEM replacement bushings. If you are good about replacing the OEM bushings/lower control arms regularly, the difference on the track is minimal. The only advantage the poly bushings have is they last longer. If you change only one set of bushings to the poly, change the rear sway bar bushings.
• Moog lower ball joints with grease fittings are very durable and convenient. Or, just buy the cheapest RockAuto lower control arms and replace them every other race or so.
• Replace front wheel bearings every 4-6 races and torque the hell out of the spindle nuts and stake them. Replace the nuts when you replace the bearings. If you wait too long, you will ruin the hubs. It's hard to find good front hubs in the junkyard.
• My attempt to cut one coil out of the original springs was a failure. They were way too stiff for any oem style strut to properly dampen. The coils front and back are tapered as well. Getting them to stay seated was problematic.
• If you are going to run LeMons and/or Chump, you are probably gonna want to stay with OEM style springs and struts. I have run Megan Racing lower springs for all our races. They are just stiff enough. The Sachs Super Touring struts that I run can dampen them. This setup works great. However, the first set of front struts only lasted about 8-9 races before I needed to replace them.
• The Megan lowering springs and Sachs struts result in about -3 degrees of camber on the front of the 626 (don't worry about the back). This is just about perfect. I have experimented with 0 toe and some toe out front and back. I always come back to 0 toe on both ends. Seems to feel best and provide the best tire wear.
• My experiment with cam style camber adjustment lower strut mount bolts was a failure. I will never use them again. If I thought I needed more negative camber, I would slightly elongate the upper strut mount holes in the strut tower and use the strut bar to keep things where I want them. I haven't had to go there.
• Torque the front and rear lower strut mount bolts before each day of racing. They have loosened up on me several times, Once, one of the rear bolts fell out mid-race. I discovered this turning in at the end of the front straight at TWS. It was quite the pucker moment when the rear wheel tried to fold under the car and refused to follow the front wheels around the corner.
• When that happened, it bent the rear tailing arm on that side. I got a set of King6 trailing arms with the Probe. So I installed those and have been using them. The difference is very subtle. Not sure I would bother buying those. I did order a set of matching King6 lateral arms at the time. But, I hated the way the sway bar links mounted to the rear lateral links. So, I never used them. Instead I bought a new set of OEM style rear lateral links from RockAuto. I don't recall them manufacturer. These links are "boxed" and much stiffer than my original 626 rear links. Not sure if the boxed links are from the 98+ 626 or if they are on other 626s/Probes. The combination of the King6 front lateral links and the boxed rear OEM links is stiff, works well, and provides some extra adjustment to increase the negative camber in the rear. The rear camber isn't all that important though.
• I originally pulled the power steering pump and looped the lines on the cylinder of the rack, leaving just enough fluid in the rack to keep things lubricated. Steering was pretty heavy and a little clunky at times. But, feedback was great. I eventually installed a rebuilt rack and the power steering pump/lines from the Probe. The car is much easier to drive, feedback is good enough, and all my teammates thanked me.

Here's a couple links you might find interesting.

My build thread.
http://mazda626.net/topic/40901-93-626-lemon-racer/

My team page on Facebook.
https://www.facebook.com/JoBoRacing

Build thread for a team racing a 2.5L 626 in Canada Chump series.
http://mazda626.net/topic/45279-98-626-chump-racer/

[dillinr]

Good pile of awesome information.

Few things I thought of while reading through it:

Brakes

- Check out Raybestos ST-43, kinda spendy but I've found many a road racer to swear by them, good bite, fade resistance and amazing long life.
- While you can't go wrong upgrading, Speed6 brakes are BIG AND HEAVY, I'd personally go for the setup that is only as big as I need, preferring to save the weight, rotational mass and cost.
- In the event of a failure, availability of replacements is something to consider. Normal 6 brakes will be easier to source than Speed6 gear.
- Stainless brake lines. Good ones. I've seen rubber ones fail.
- Use ducting instead of removing heat shields, the shields keep heat of suspension components and extend service life.

Wheel bearings, WTF, 4-5 races?? I've been doing autocross and track/lapping days on the same four wheel bearings for 8 years now, over 40k miles, most of it on Hoosier A6 gumballs...do they really go that fast under the stress of endurance racing, or just precautionary?

Toe out, agree, any on the race track is wasted and probably hurts straight line speeds and wears tires unnecessarily. However for autocross it's magical...

Head gaskets really a problem on the KL? Again, years and tens of thousands of miles to/from track and no problems, even 105deg ambient temps...But again, not endurance racing for hours at a time.

[majo8]

I met you at the Barber race in the line waiting to get in Friday evening. I race a Probe in LeMons too, and we chatted a bit. I wondered what happened to you guys! I raced a purple 4-door Escort and a Kia covered in astroturf at the Barber race -- the Probe was at home in my garage.

Good info from racerxr and dillinr. Not much to add, except what we run and our experiences.

Suspension is Tein sport springs and Staggs struts. I really don't know how much better it handles with these springs. Camber is roughly -1.7" front ( maxxed out ), and slightly positive in the rear stock. We run just a touch of toe-out in front, about 1/16", and it handles better than when we had slight toe-in. Mazda 626 bar out back. Brakes are a regular Mazda 6 set-up with Raybestos ST-43 pads -- outbrakes over 80% of the competition. Steel brake lines. Our bearings are originals, and have lasted seven races -- it wouldn't hurt to change them eventually though.

Engine is stock with Fidanza flywheel and ebay header. Has 131k, and almost 100 hours of race abuse. I reckon we've been lucky compared to how these engines like to nuke themselves in LeMons. We do try to keep the revs under 6400. Runs hot -- usually around 210-220 with stock cooling set-up.

Please keep us informed of your progress! I'm planning on Barber again in February, racing a friend's Celica. Hope to see ya there.

Our Facebook link is below if you're interested.

[dillinr]

210 to 220 water temps is pretty safe. It's when you start getting over 230 the problems really start happening for most cars. Honestly not sure on the KL though, never had any problems

[RacerXR]

Good pile of awesome information.

Few things I thought of while reading through it:

Brakes

- Check out Raybestos ST-43, kinda spendy but I've found many a road racer to swear by them, good bite, fade resistance and amazing long life.

I've heard good things about ST-43's as well. They are just too darn expensive for me. Hawks work like a champ, last 3-4 races, always bed perfectly, never develop uneven deposits on the rotors, and are reasonably priced (especially with the WRL discount). I have no reason to try anything else.

- While you can't go wrong upgrading, Speed6 brakes are BIG AND HEAVY, I'd personally go for the setup that is only as big as I need, preferring to save the weight, rotational mass and cost.
- In the event of a failure, availability of replacements is something to consider. Normal 6 brakes will be easier to source than Speed6 gear.

I agree with this. To do it again, I would likely go with the Normal 6 rotors and calipers up front. The Speed 6 rotors weigh a ton. All that rotating mass hurts acceleration and likely added to the early demise of my front struts.

- Stainless brake lines. Good ones. I've seen rubber ones fail.

I've seen stainless lines rub and fail too. I think you could fail either way. That being said, I have been running stainless lines. However with the crazy initial bite the Speed 6 rotors have, I have considered switching back to rubber lines up front.

- Use ducting instead of removing heat shields, the shields keep heat of suspension components and extend service life.

I can't argue with this. All the heat is not great for your ball joints and outer tie-rod ends. In my case, the Speed 6 rotors run so cool and I have zerk fittings on my Moog ball joints. So it hasn't been a big problem for me. However, I suspect that the cheap lower control arms no name ball joints would have lasted longer if I kept the shields.

Wheel bearings, WTF, 4-5 races?? I've been doing autocross and track/lapping days on the same four wheel bearings for 8 years now, over 40k miles, most of it on Hoosier A6 gumballs...do they really go that fast under the stress of endurance racing, or just precautionary?

Yep, new front wheel bearings will fail after 6-8 races. So change them after 4-5 (or 6) races. I basically do it once a year. Of course, this will depend on how hard you are driving the car. We have 3 top ten LeMons finishes in our 2.0L 626. It's very much a momentum car and it is pushed hard in every turn for 16 hrs every race weekend. This is nothing like street driving. Failure points are very different here.

Lastly, counting just expendables (fuel, tires, brakes) and entry fees a LeMons/Chump/WRL race weekend will cost a team well over $2K. Don't let a set of wheel bearings send you home early. In fact, I have an extra set of spindle/hubs (usually my old set) on hand just in case.

Toe out, agree, any on the race track is wasted and probably hurts straight line speeds and wears tires unnecessarily. However for autocross it's magical...

I believe that.

Head gaskets really a problem on the KL? Again, years and tens of thousands of miles to/from track and no problems, even 105deg ambient temps...But again, not endurance racing for hours at a time.

As I pointed out, this is nothing like street driving. Failure points are different. To be honest, I have never seen a 2.5L Mazda motor run all weekend at a race I have attended. However, I know that they do finish.

The key to endurance racing a factory motor is keeping the revs down. This why the Mazda BP and FS-DE motors do well. They make lots of torquey mid range power and don't need to be run right up to the factory red-line. This is also why Honda motors blow head gaskets very regularly. They have a worse record than the 2.5L motor. The best way to keep a Japanese motor running all race weekend is to keep rpms at least 500 rpm below the factory red-line. On my FS-DE motor, I have the shift light set at 5200 rpm. On my fastest laps, I usually never even see the light.

[rmlunsford]

I met you at the Barber race in the line waiting to get in Friday evening. I race a Probe in LeMons too, and we chatted a bit. I wondered what happened to you guys! I raced a purple 4-door Escort and a Kia covered in astroturf at the Barber race -- the Probe was at home in my garage.

I remember that bad machine!

Engine is stock with Fidanza flywheel and ebay header. Has 131k, and almost 100 hours of race abuse. I reckon we've been lucky compared to how these engines like to nuke themselves in LeMons. We do try to keep the revs under 6400. Runs hot -- usually around 210-220 with stock cooling set-up.

We don't rev it too high and it runs in that 210 range but it hit 230 at barber and I think that is when that piston burned. Plan to put in a larger radiator for this next go around. I don't think we'll make Barber as it's during Mardi Gras, probably looking at Dallas in April.

[majo8]

To be honest, I have never seen a 2.5L Mazda motor run all weekend at a race I have attended.

Hmmmm. Please let me know if you're gonna attend the same races as me in the near future -- I'll bring the Imperial instead of the Probe!

[dillinr]

Rubber line failure wasn't from rubbing, the rubber hose simply popped out of the crimps at the ends. Poor guy I have in mind had it happen twice, once on an STI and again on a Cobalt SS...Rolled that one, total loss, thank heaven he wasn't badly injured, one of my favorite local racers. Lesson learned the easy way...stainless lines are cheap insurance.

Still surprised at the wheel bearings...I know Honda's have massive issues as well, but theirs are smaller than ours...I wonder if it's a lubrication issue, perhaps the grease is breaking down due to prolonged heat. Maybe worth taking one apart, cleaning it all up and installing some special high dollar synthetic wheel bearing grease. Redline makes some. I know some Honda guys have had success with extending their change intervals.

Have either of you guys raced at the former Miller Motorsports Park?

[RacerXR]

It's a pretty standard practice to change the front wheel bearings on any FWD road racer at least once a season. So, it's not a ding on the Ford/Mazda. The front wheel bearings are actually very beefy. But, I have killed one and nursed it to the finish line one weekend.

I haven't raced Miller.