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Member Since 04 Aug 2009
Offline Last Active Yesterday, 09:14 PM

#111691 Goals for 2019

Posted by Shuka on 09 January 2019 - 05:07 PM

1. Build a big steel building

2. Put Miata things in big steel building

3. Maybe find time to race

#111677 I designed a Blipshift t-shirt

Posted by Shuka on 08 January 2019 - 10:59 AM

Super awesome! Congrats. I ordered one! :)

#111619 Street tire class NASA

Posted by Shuka on 04 January 2019 - 06:42 PM

100 TW would be preferable for sure - Maxxis are my cheap go-to's. They last forever, have decent grip, and they're cheapish!

#111614 Street tire class NASA

Posted by Shuka on 04 January 2019 - 04:14 PM

To expand, I think specifically it will attract:


-Newcomers to TT, who don't want to pony up for R-comps but still want to compare lap times to similar cars

-People that drive their car to the track and don't bring a second set of wheels

-WRL cars that run 200TW, for testing or to just get seat time


And to be honest, back in my more economical TT days, I was running 200 TW tires - and ended up on the podium sometimes to boot! Plus you have the eternal excuse of "I'm on street tires LOL!"

#111612 Street tire class NASA

Posted by Shuka on 04 January 2019 - 04:04 PM

Heck, why not give it a chance? I think ultimately it will encourage more participation in TT, which means more contingency, and more people that end up in ST doing actual racing.


Worst case everyone hates it and we declare it a failed experiment, but I honestly think we'll have fun with it.

#111328 lobster car or how to choose seats?

Posted by Shuka on 23 December 2018 - 01:17 PM

I got my 14" joes racing mirror today and well...I hate it.    


Everything seems so far away and wrong it's going to take forever to get used to. 



I may return it and look for another mirror that isn't so convex?  



ETA: holy shit we posted at the same time.  


i debated making that same joke damnit. 



I need a mirror to know when I should let the miatas by.    Still won't... I would just like to know. 


The convex takes a while to get used to, and placement is key. I tried a wink mirror (the kind with a bunch of small mirrors at an angle mounted in it) and hated it.


My most useful mirrors are the convex spot mirrors added inside the car at the corners of the windows. That's where you *need* to see more than anything in any sort of W2W. Again, the distorted view takes some adjustment but I have grown to love them. They're particularly nice because they see around the window net, and show you all the way down the side of the car.

#111114 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 17 December 2018 - 10:06 AM

I didn't want my exhaust sticking past the rear bumper, in case of impact (been there done that, a rear impact will tear up downpipe, header...) so I made a piece to fit the rear bumper to extend the exhaust.


I like it, it looks cool, BUT I can see the cross beam through the hole, which means it's not ST5 legal.


So I patched it up ( the other patch was the previous owner's work - the bumper was all melted from exhaust tip contact.) I instead just turned the exhaust downward.)


I paid a visit to Metal Supermarkets for some aluminum sheets. A sponsorship would be nice considering how much money I spend there...


I replaced my 0.030 sheet over the tire well with a 0.090 sheet, and made it larger too.


With a new harness / ECU on order with 4-5 week lead time, I decided to just re-do every scrap of the wiring in the car. Again. I had built the last iteration around some terminal strips, which worked pretty well, but i didn't like the number of failure points and lack of accessibility:


Everything stripped out:


I also started on the radiator ducting and hood work.



I built a nice curvy piece to hump over the valve cover:


But I settled on a flatter piece that I'll graft a small hump onto for clearance:


You'll notice that I cut the hood all the way across. With the forward mounting of the radiator and larger duct, there wasn't enough hood left at the front to warrant keeping it. The headlight door section will be stationary, and the hood will lift with the curved portion attached allowing access to the motor.


It should look something like this when it's finished:


#110707 WRL @ COTA (Dec. 1-2)

Posted by Shuka on 28 November 2018 - 07:38 AM

You can also make a quick trip to Winding Road in Austin, which can get you completely decked out.

#110653 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 26 November 2018 - 08:52 AM

Awesome! I've ways had my eye on the ecotec swap. I'll be bugging you for a ride when you have her running [emoji3526]

Unfortunately, the passenger seat will be replaced by steel plates for ballast. I'll need upwards of 200 lbs (and maybe up to the class allowed maximum of 250) to hit ST5 225 tire weight (2400 lbs.) On that note I have had to reverse my mentality. With the last prep round I was shaving ounces and pounds anywhere I could. This time it's the opposite; looking for places to add brackets and bars and extra safety stuff.

A few days off work for Thanksgiving gave me some great opportunity to get stuff done on the build.

Painted throttle pedal assembly before installation. It will definitely need a pedal cover to make heel-toe practical. 


My previous exhaust had rubbed on the band holding the grease boot on the CV joint. I figured it was a good time to rebuild both.


I pulled the boots apart and disassembled the CV joints, then cleaned out all the old grease. After shooting the parts with brake cleaner, they looked nice and clean.


Both cages let the bearings pass right through. These are OEM junkyard pulls from what I know, and are definitely NOT fancy modified "fast" Spec Miata CV's.


CV repack kits from Mazda come with boots, clips, and grease. It was a messy, but pretty easy job.


On to exhaust finishing touches. I had to make a custom "hand forged indentation" so the clutch fork would have room to travel.


Exhaust mounted on the car. I'm working on a fancier solution for exit through the bumper, so if I'm tapped / hit it won't just kill the exhaust.


My solution to keeping the system from swaying back and forth:


On the fueling front, I had an issue with fuel cut under hard cornering. My best guess was that bubbles in the filter canister, which was mounted horizontally, and between regulator and fuel rail, were the issue. So I changed the location to the lowest point in the system, tilted it so the outlet faces upward, and put the filter between the pump and the regulator. There will be constant flow from the pump through the filter and back to the tank, but any bubbles should quickly work themselves out.


From the top. All of the fuel handling stuff is in this compartment, which will dump below the car if there is a leak (and not in to the passenger compartment.)


Back to some metal fab work. I made these little tombstones to mount the radiator to my new core support beam.


I also added some connecting tubes between the core support beam and the bumper bar.


Radiator mounted.


16AN hoses routed. I will be ducting the radiator out the hood again, so the hoses go around instead of through this area.


The Ecotec swap kit came with a silicone elbow and a tube, locating the filter in the engine bay. I already had the hole through to the wheel well, so I threw together an aluminum intake tube.


Intake tube mounted up.


Back at it, time to get this thing on the ground.


Refreshed control arms with new bushings and Zerk fittings.


Rear assembled. I re-installed the parking brake kit. The FM kit adds some levers to a standard Wilwood caliper, so that pulling on the cable pinches the levers and pushes the pads against the rotor. The hubs came from the Miataturbo group buy, beefier and with ARP studs.



Car on the ground! I'm sure it will be up on jack stands at some point soon, but all the work under the car is done for now.

All I need for a running motor is the shipment from Alphafab, which has the wiring harness, ECU, and a few key adapters and bits.


#110585 Is it ok to run this pad?

Posted by Shuka on 21 November 2018 - 11:29 PM

Yes. Many pads don't even come with that clip. 100% OK to run without it or if it's loose.

#110469 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 19 November 2018 - 08:27 AM

What considerations have you made for heat shielding that exhaust? It looks like there will be a good bit of heat transfer into the floor of the car. May get mighty toasty in there!!
Your TIG welding is looking awesome! Looks better than some people's I've seen who've been doing it professionally for a long time....

We were talking about heat shielding last night, as well as the definite issue of exhaust bumping the body and PPF. I had to make it hug pretty close, and there's just no wiggle room. We're thinking silicone (like an oven mitt) to protect from both heat and bumping. I'll also add some shielding inside.

Test fit of the hood. It would definitely fit under a stock hood if with a bit of skeleton trimming. This one will get the full ducting treatment though.

While you can opt to use a cable actuated throttle body, the OEM and easier configuration is to use drive by wire. The original Miata pedal needs to be replaced with a pedal from a Cadillac CTS.


The pedal comes with a hefty steel bracket, which I modified to graft on to the Miata's pedal frame.


I welded the two together, on top and bottom. I'll add an extra bolt or two from the new pedal's mounting tabs to the car.


All finished up. The pedal sits almost exactly where the Miata's pedal did. I'll need a pedal cover or extension to heel toe effectively.


And on to finishing up the exhaust! Building an exhaust without a lift becomes a lot of core exercise, since I'm shimmying under the car repeatedly to test fit things. Final welds on the exhaust run:


Using my press to bend the hanger rods. I had a face shield on while operating this janky thing. It worked great though!


A Flowmaster muffler for the rear.


Full exhaust complete with hangers!



STILL no word from Alpha Fab. It's been a full month since I ordered the ECU / harness. :( Probably should have chosen another shop.

#110352 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 14 November 2018 - 08:08 AM

The exhaust is all cut and fit now. It hangs down maybe an inch toward the back, but otherwise is above the frame rails.


I didn't want to open the garage to weld last night so I started assembling stuff. I picked up some new cam and crank bolts from the Chevy dealer down the street... stretch bolts are weird. With those installed I bolted up the valve cover, and then just went to town.

New seals for the plastic intake manifold. The blue blob of RTV in the middle is the PCV system. I drove a screw into the little orifice, then jammed a bunch of RTV in there to make sure it stays put. According to other Ecotec owners, with heavy track use the car draws too much vacuum through this system and the prescribed fix is to just seal it up.


Intake manifold, new GM drive-by-wire throttle body, freshly cleaned injectors and fuel rail.

Thermostat with spacer, water inlet manifold, header and O2 sensors installed. Spark plugs and coil packs too.

Dipstick installed. With this I'm pretty close to a first start. I just need the harness and ECU (and, well, a cooling system)!


#110321 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 13 November 2018 - 09:55 AM

Dude - That is awesome in my book! I need a v-band interface and a flex joint installed in my stainless exhaust, do you take freelance track junkie welding requests in exchange for beer haha!? Halfway kidding ;)


Totally stole your drift armor bar idea BTW, to weld brackets for cooling stack ducting and my splitter support frame to...


That would be a pretty straightforward job on the exhaust, and you're in the neighborhood, so sure!


I still need to build radiator supports and some sort of mount for the hood pins, but that's later. I'm currently laser focused on getting the exhaust done :)

#110276 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 12 November 2018 - 09:12 AM

@Shuka, are you planning any supports for the header/manifold/downpipe structure? It looks like a lot of mass being supported at the head. I would be worried about the exhaust cracking somewhere with constant engine vibration.


Supports are coming! It's a project in itself due to exhaust on the "wrong" side of the car.

#110273 The LE5pard - Nix's Ecotec Miata Build

Posted by Shuka on 12 November 2018 - 08:15 AM

Clearancing isn't allowed, but strengthening is.
I guess the theory is that a major weight reduction could be done in name of "Clearancing" if someone was feeling sneaky.


It's allowed, but only what you can get out of a 3/4" hole:


1a) Frame rails, sub-frames/suspension cross-members, and unibodies may have maximum diameter 0.75” (3/4 inch) holes drilled into them for purposes other than lightening, such as for the attachment of ancillary parts. Cutting and channeling is not permitted.


Waiting on the head, I built a quick bracket for the STEAM BOMB coolant reservoir.





I got the head back from the machine shop on Thursday, which meant a  weekend of big progress. I used ARP head studs this go around. You can see the guts of the Ecotec Miata swap kit in this picture. There's an aluminum adapter plate to match the Ecotec to the Miata's bell housing. I'd feel better if it were steel. I had to grind on one of the machined recesses for the mounting bolts, as it wasn't deep enough to allow the bolt head to sit flush. 


The stock flex plate is installed, then the Ecotec Miata adapter puck, then an OEM Miata flywheel.




The engine dropped right into place.




I replaced the timing chain set right after installing the engine. It's a pretty simple process. 





Priority one at this point was to figure out exhaust. I knew the fit would be tight through the OEM subframe, but until the transmission, slave cylinder, and PPF were in place I had no idea if 2.5" exhaust would work.


The header is for a Polaris Slingshot, which uses the GM LE5 as well. The only place for a pipe to go through is that little gap between subframe, slave cylinder, and tunnel:




The good news: A 2.5" pipe can get through. Bad news: at a weird angle and just barely.




With that, I got to work! I came up with a trick to fit pieces of pipe together for test fitting. I loosen the clamps just enough to allow adjustment, but not so much they slip out of place:



Carefully fitting, welding, testing, fitting, repeat:




Tackling the super thick flange:




Another test fit, making sure to install the gaskets and get everything tight:




And we have a downpipe!




I mulled over bringing the exhaust over to the driver's side (under the transmission) or through the PPF, or deleting the PPF entirely. I settled on routing the pipe along the PPF down the passenger side. Sunday's project was getting from the downpipe to the differential:




I'm getting halfway OK at TIG welding stainless!



Not a perfect, rainbow colored stack of dimes, but close enough for race car!