Kraze's "The Reasonable Thing" kind of build

Nice swas switch. I was considering doing a switch back in 2016...but it was far simpler to just unplug it in whatever parking lot I found myself in at the time haha.

goodluck on your event! I’m still dying to get on track this season.

 

I have successfully torture tested, I mean, autocrossed, the speed. I made a new thread in the autocross section (that section seemed dead so I figured I'd try to breathe some new life into it lol) with the in-car footage, found here: https://mazdaspeeds.org/index.php?threads/krazes-kill-all-cones-thread.12731/

I'll leave this thread for discussing the build related things I discovered.

1. Holy temps BATman! Obviously a TMIC is not the best way to go about an autocross car, and the reasonable thing to do would be to go FMIC, but a top mount is what I have/am tuned for right now, so that's what we're working with. Anyway, I believe the point where Will starts nerfing the power is somewhere around 190 BATs and 6k+ RPM (maybe other factors going into it as well, but that's what I see so far). Check out the APP vs TB position and WG duty cycle on the end of this run lol:



I'll be doing some experiments on how to better cool the intercooler off between runs before this next event. Spritzing it down with water doesn't seem to be doing the trick enough to keep me out of trouble lol.

2. I'm experiencing a major front end pop/clunk when the front end is really loaded, especially heavy braking zones. Coupled with the fact that I'm also experiencing the dreaded 2nd gear pop out, and I still have OEM TMM and PMM, I'm hoping that it might just be an issue with those. So new Damond side mounts in their new street stiffness have been ordered, along with the Cobb lighter shift weight. Hopefully that will solve both the loud pop and the pop out issue. I'm also going to do a full bolt check on the front suspension components just to make sure it's not something loose causing the sounds.

3. I need to bleed the brakes better. Braking power is good, but the pedal feel isn't the greatest.

Overall though, it was a good shake down run! I just need to make the above changes and get a ton more experience as a driver and maybe I'll be locally competitive at some point haha.

 

Those bats are ridiculous!!!!! I know ko4 is just a hairdryer but that is insane!!! When I had my big ass oil cooler(it’s the size of the oem top mount) DIRECTLY in front of my front mount....20 minute lapping sessions and I’d still only hit maybe a max of 70-80c(160-175f) bats and that was giving me massive stress. Your bats? I have too much mechanical sympathy to operate the car at wot at those temps. Is the thing even making power at that point? Maybe 190whp lol. Your ducting either sucks bad(I know you’re missing the oem shit) or something else going on there. I’d address that before even doing anymore events. The power drop off alone has got to be enough of a disadvantage to you in itself.

I mean if you aren’t knocking it’s probably ok? But still DAMN lol.

To give you some idea, the CX racing kit, with its crappy eBay garbage core, is able to keep my buddys ms6 bats below 190 for a couple of hot laps at the track. Just to give you some reference. People scream to throw the CX core directly in the trash but here it is sucking less then the CS top mount in your setup.

 

Haha I did say that it was a torture test Surprisingly, before the tune/ECU starts yanking the power, even with the crazy high BATs, there's still more power available than I can use at my current skill level. And also surprisingly, I never had any serious knock either. I maxed at 0.7 KR for both days I think, and that's over a rough airfield so who knows if it was real knock or not. But yeah, once I hit whatever the parameters are where the car kills the party, it feels like I'm back on the K04 when it hits 5.5k RPM lol.

I do suspect autocross is just about worst case scenario for an intercooler though, especially a top mount. With road course stuff, even with the shitty ducting of the 1st gen, there's just so much more air available to cool it down with the speeds you see. With autocross, we get up to 60+ mph very briefly a couple times in the run, then park it in grid for 15-20 minutes while the motor heat soaks it some more, then go out and do it again, and it just never gets a chance to cool off. We'll see how the testing goes with icing it down instead of just spraying water at it. I might end up with a FMIC sooner than expected if I can't figure something out lol.

 

Definitely worst case scenario for any intercooler, never mind a top mount lol. Definitely HOT. 0.7kr is nothing so I would say you’re ok. A fmic would at least help as it wouldn’t just be baking from the engine heat. Maybe a future mod to really consider if this will remain an autox build?

 

Oh yeah, as soon as I saw how high the BATs still were going into the 2nd run on the first day, I knew I probably messed up going top mount haha, so a FMIC is definitely on the table, and will most likely happen at some point no matter what now. But knowing that the throttle will start closing, and the wastegate will start opening, when things get too hot to keep me from doing something really stupid is at least a bit of relief while I'm still TMIC.

 

I had similar safeties in place on my stock block setup. Only difference was the max bat limit was much, much lower lol. Just out of habit I have/continue to build the car for maximum efficiency and COOLING.

 

Couple more things done on the speed. The AC hasn't been working since I bought the car. Come to find out, the radiator support damaged the AC condenser and it had a leak, so I had to replace both. Now it still doesn't want to work unless the system is overcharged, and the compressor is making some noise, so I'm going to replace that and hope then I'll finally have working AC!

Also, I installed the Cobb shift weight and the Damond PMM and TMM with the new soft bushings. I've never personally experienced the Damond mounts with the "race" bushings, but man, these soft bushings are exactly what I was looking for! I was seriously considering throwing new OEM mounts on for the sides just to keep vibrations down, but these new soft bushings have added no noticeable vibrations or NVH, so I'm extremely pleased. Now I'm just crossing my fingers that between the new mounts and the Cobb shifter weight I won't have the 2nd gear pop out issue when autocrossing the car.

 

Dear diary: It happened again today. For the fourth time in as many months, I found myself standing there in the darkened garage, blood dripping from my knuckles, fuel door open, watching the match slowly burn towards my fingertips. I wanted to drop it in there. I really did. I imagined the wave of relief that would slowly come over me as the flames licked the red paint, the toxic fumes filling the garage, all of my frustrations slowly going up in smoke.

It wasn’t a singular event that brought me to this point. It never is. No, it’s the accumulation of “fuck-you’s” thrown my way by this spiteful creature known only as the demon speed 3. It starts out with minor affronts: the AC line disconnect tools popping off into the abyss known as the engine bay, never to be found again. The lacerations to my knuckles from attempting to find said AC line tools. But these minor affronts slowly build into a raging crescendo, peaking this particular time with the stripping of the expansion valve bolt.

Ah, the glorious expansion valve. Brilliant Mazda engineers decided to tuck this little piece of mechanical wizardry way back up under the dash. They didn’t want mere mortals to be able to easily access such a fine piece of engineering. No, putting it somewhere that doesn’t require you to stick your head in a hole where a glove box used to be while contorting your hands and arms to snake around wiring harnesses and AC lines would be far too reasonable!

But I digress. And the match burns out. I go to strike a new one, but that was the last one in the box. One last “fuck you” thrown my way, I suppose. I guess the Mazda is saved from a viking funeral for one more day.


Edit: Oh shit. Well, this is embarrassing. I thought I had clicked in to my diary, but I guess I accidentally had clicked into my build thread.

But in all seriousness, if you have a genius idea on how to remove this stripped allen bolt from the expansion valve (that hopefully doesn’t require removing the dash), throw it my way ASAP. I’m thinking about drilling it, if I can even fit a drill in there. Then maybe a screw extractor, or some form of extractor. I’ve already tried hammering a torx bit in there to see to see if it will bite enough to remove it, but we can all guess how that turned out.

And what good would a novel of a post be without pictures. The bolt I was able to remove is corroded as all hell. I guess that explains why they’re being such a pain in the ass to remove.

 

Can you jam a flathead screwdriver in there?

 

I hadn't considered trying to jam a flathead in there as is. It's worth a shot though! I had to walk away from it last night. I went into town and picked up a couple straight extractors, a spiral extractor, and a couple cobalt drill bits. I'm hoping I can remove it by jamming one of these things in there and not have to drill it. Just really not confident that I can drill it straight given its location lol.

 

Finally got it out. I ended up having to drill it and use an extractor on it. What a stupid, stupid place to strip out a bolt head lol. Of course, I took this opportunity to buy a new tool. Never pass up an opportunity to justify a tool purchase, that's my motto.

So far in my pursuit of functioning AC I have replaced: the radiator support, the condenser, the compressor, and now the expansion valve. Fingers crossed that does the trick.

 

Looks like fun, good luck, AC leaks can be maddening.

 

Well boys, we have AC now, and it's blowing real cold! Considering the northwest has been in a perpetual heatwave all summer, this will be a welcome addition.

The next autocross event is this weekend, but I'm in a dilemma. The highs will be 100 one day, 95 the next (38 C and 35 C for our Canadian friends). I think the highs were around 80-85 the last time I was out when I had the problems with stupid high BATs. I know I need to do something other than spray water on the TMIC to try and cool it off in between runs, I'm just not sure what the most effective method will be.

Unfortunately, it looks like we're in a dry ice shortage up here at the moment, so that's out. I might try to do some testing today/tomorrow with traditional ice to see how effective that can be given the average time I will have to get things cooled off a bit. Anyone have any unconventional wisdom to offer for icing down the intercooler, besides just pile as much ice as I can on it and hope it cools down enough?

 

A lot of ice water

 

Bags of ice, ice water. Yea. That’s about it

 

Do you have all of the stock ducting intact?

 

That's kind of what I figured, I just wanted to make sure there wasn't some super secret way to more effectively ice it down lol.

Yep, it's all there, the underhood ducting and the intercooler cover. And I cut the mesh part off of the cover so I can set the ice directly onto the intercooler.

 

You could always get a 12 volt computer fan and wire it into a switch so it blows air onto the TMIC. My friend did something like that for his Subaru. He took a flexible duct and ran it through the fender towards his air filter then added a computer fan pushing air into the filter. It worked and decreased his IAT slightly. He set it up for key on operation plus since the fan is small it doesn't draw a ton of amperage.

 

Now there's an idea I hadn't considered! I'd thought about buying a portable, battery powered fan just to throw on top of the TMIC while parked in grid, but a small computer fan or two might make even more sense! Plus as you said, they don't draw much power and could run all the time.

Very interesting, I'm going to have to give that one some thought!