KMiata SCCA Solo XP swap

aMaff

High Speed Low Drag
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1992 Miata / 2003 Pathfinder
woohoo I've made my first AN line! ....god I hope they don't leak :lolsob:





2 more down. Gotta wait on the rest of the fittings to come in later this week.



Also waiting on some line separators to keep everything tidy and from rubbing anything it shouldn't.

I was trying to figure out how to mount the E85 sensor



But then the internet came to the rescue:

https://www.thingiverse.com/thing:2965407



Apparently I'm not the only one to have had this issue before. So, I've got a buddy with a really good 3D printer cooking one of these up for me.
 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
Fuel system progress.

I need to close the holes in the package tray up, and a couple spots need chafing protection. The reg and filter took up way more room than I was expecting, hence putting it all in the trunk.






This one'll also be getting a panel to keep rocks from the tires away from it (or I might try and find the stock one). I mean, the brake lines have been fine for years naked, but while brake failure isn't great, it's less likely to set you on fire...



I also made a standoff / hose stay out of a scrap bit of hose (and used another length to keep the zip tie from chafing it) to keep the fuel line from rubbing the brake hose.

 

aMaff

High Speed Low Drag
Moderator
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1992 Miata / 2003 Pathfinder
I'm normally not shy about getting out the cutting tools, but hacking into a nice, cast aluminum bell housing (even if it's to an empty case that I have for exactly this) gave me the heebs. That said, it's serving its purpose (mockup), and I'll know how to do the quaife box a good bit better.







 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
Eating the elephant 1 bite at a time.



I should have it mocked up in the engine bay tomorrow so I can bolt everything in and finish running fuel lines, start running coolant lines, and generally figuring out where everything wants to live.
 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
This happened today.



Of course after I finish up all the hose routing, it all comes back out again to fix a few issues and get nut-and-bolted (again), but it's a big step.
 

aMaff

High Speed Low Drag
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1992 Miata / 2003 Pathfinder
I wanted a way to run the upper radiator hose for the K24 from the driver's side rear of the head under the intake manifold and forward to the rad. I, at this time, will need 3 different hoses / tubes to make that happen (90 deg rubber to turn the corner to run under the intake manifold, a 90 right/ 90 left to get from the upper radiator around the front of the head, and an aluminum piece to connect the 2). But there's a whacking great big stock tensioner pulley mount over the water pump housing in my way:



So I broke out the cutting tools and did it in small bites to make sure I didn't cut into the PCV channel that runs underneath it.



Absolutely COVERED that side of the engine bay in aluminum & WD40 schmoo.
Yes, the bodywork is black.



But now the hoses can meet:



A little more time with the flap wheel (and more WD40...) and it actually looks presentable.

 
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aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
Had the day off. Ended up burning most of that ferrying a kid to the doctor (yay strep throat!) but managed to get in the shop for a couple hours to knock out a few things.

1st up was fixing the clearance issue (another V8Roadsters hit!) between the 'intermediate' header pipe flange and subframe. There's nothing like taking grinding tools to freshly ceramic coated parts. I know I know, I should have test fit them first.

The flange for the lower tube hits a gusset in the subframe:





Next I finished up the fuel system. The hose that runs near-ish the exhaust to the flex-fuel sensor behind the head got some of that pimpy heat protective insulated shrouding. That stuff is a PAIN to put on, but worth it. I'll likely want a heat-shield there as well for the full belt & suspenders, but it won't be worse off for having that stuff on.



And my bead-roller came in (I bought a real tool!) so I knocked out the connecting tube for the upper radiator hose.

 

aMaff

High Speed Low Drag
Moderator
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1992 Miata / 2003 Pathfinder
It's no secret that I don't like the way they tension the accessory belt in this swap. I absolutely believe them when they say it works and is reliable on their & their customer race cars, but I picture myself in a wet, gravel or sand paddock space at a track or on the side of a mountain, needing to replace an alternator or water pump, and losing half of those damn washers in the dirt.
Given that, I had grand plans of turning up a couple sets of custom length spacers (one to have as a spare) on the lathe, until a different option was presented.

The alternator on the 08+ Accords and 09+ TSXs (from a K24z3, vs the K24a2 that I have) has a single-bolt bottom mount that runs parallel to the engine. IE: It can swivel. IE: If I can figure out a way to make that work, I can use a simple turnbuckle style tensioner and never worry about losing a boatload of small parts just to change a belt.

The alternator mounts on the side of the "water housing". A weird aluminum casting that bolts to the driver's side (in this RWD configuration) of the engine that the water pump bolts to in the front, the thermostat housing bolts to in the rear, the alternator on the side, and the big stock tensioner bracket (that I cut off to route the coolant hose) on top. It *appears* that I can simply swap to a later water pump housing
Off to EBay to load the parts cannon!

I got the z3 water housing in and things looked ok to start with, but I found 2 problems.

1. the bolt bores are different sizes / lengths. The z3 housing uses 2 long studs (vs 1 long and 2 short), and then 1 long bolt and 1 short (vs 2 long). That's fairly minor, I just need to grab a stud and bolt. I could honestly get by with 3 bolts, but the studs help when sliding it on the first time when it's covered in RTV so I don't screw that up horribly.

2. This one's bigger, and will require a little help from my friends. The K24z3 housing is on the left, the K24a2 housing is on the right.
The z3 housing uses 3 of the 4 bolt holes the same as the a2, but the one at the upper right (sharpie pointer) is in a different location.
HOWEVER: The hole from the original a2 pattern is *nearly* drilled through in the z3 housing so I've got something to work off of.



I didn't want to have my machinist go through all the trouble of milling this thing down if the hole pattern wouldn't line up, so I used a slightly undersized drill-bit to knock the bottom of that bore out. This way, the original bore is still there to locate an endmill off of to bore it correctly.

That top bolt is actually tight but it's sitting on that step in the casting on the back side of the bolt. We (and by we I mean Dave) will mill in a flat for the bolt to sit flat against.



The alternator and a turnbuckle that looked to be about the right length are coming in on Thursday, then I can play around with where I want to actually mount the thing. I might use 1 of those bosses at the top, I might pick up on 1 of the water housing bolts. We'll see.
 

aMaff

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Moderator
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1992 Miata / 2003 Pathfinder
Got the cooling system pretty much wrapped up, I think. Probably going to put some more anti-abrasion sleeve and a bit of retention where it wraps around the front of the engine, because while it doesn't touch while not loaded, I imagine when it's full of water and moving with the car & engine, it'll definitely rub there. Worst case it's easy / cheap insurance that I'm not wetting down the course / track.



 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
More alternator progress. I hacked off part of the stock tensioner mount on the pump housing to clear the coolant hose, and mocked up a bracket that SHOULD work until my machinist friend has his way with my housing (#MiataThings)

If I DO go that route, it will be prettied up (and lightened up) a good bit. I just wanted to something that would do the job even if not the prettiest thing in the world. It does foul the upper coolant hose to a small degree, but could actually be used to mount a clamp to secure the hose with little extra work.



Option 2 is probably ideal, and what the next iteration will likely be. Probably a bracket that picks up off that mount bolt for the pump housing (and locates into that corner so it can't rotate)

 

aMaff

High Speed Low Drag
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1992 Miata / 2003 Pathfinder
I get that it's just a bracket with 3 holes, a turnbuckle and a couple bolts, (and at this early stage, damn ugly), but I'm genuinely proud of this silly thing. If you'd have told me I'd be building my own belt tensioners 15 years ago when I could barely change my own oil, I'd have laughed at you.





It also probably won't be the final iteration, but it's simple and works, which I'll take for V1.0
Or I guess 2.0, really
 

aMaff

High Speed Low Drag
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1992 Miata / 2003 Pathfinder
I've gotta tell you, even though it's still missing several VERY important parts, the fact that it's starting to look like an engine is highly motivating :D

 

aMaff

High Speed Low Drag
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1992 Miata / 2003 Pathfinder
Bah.
My rad bazooka tube intake created an interference with the upper radiator hose. Because sometimes I have a startling lack of foresight (or optimism...)




So, options.
I call this one "The Nessie"




This however is certainly the easy solution:



I plan on keeping The Nessie on hand for when this setup gets dynoed. If it makes a significant difference, I'll definitely find a way to make something like that fit.
 

aMaff

High Speed Low Drag
Moderator
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1992 Miata / 2003 Pathfinder
I put together another piece of the puzzle by building the most Miata bracket of all time. I haven't yet decided if that's a scrote or a mushroom tip (rlaugh)



The bracket I had bolted the catch-can to made it foul on the intake manifold (now on the wrong side). The engine being canted over towards the exhaust side made putting it over on that side inconvenient (plus much longer line runs, as both vents are on the intake side). Putting it 'higher' in the bay meant I'd need to grab a more compact rectangular catch can vs the cylindrical one I already have.

Here's where it was with the BP engine:



I figured I'd need to rig up some rivnuts to bolt it to the inside of the frame rail, but poking around under the car, I found a couple of handy threaded holes in *exactly* the right place to make my life easy.
There's a good deal of clearance to the lower radiator hose, despite what the depth of field in the photo would have you believe, but I have since rotated the lower fitting an extra 90 degrees so that it's even further from the hose.



 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
Got the engine out (for the last time, right? RIGHT!? Riiiiiiiiiiiiight) this weekend and got started on the punch list.

Bashed this lip back for clearance for the passenger side upper-rear corner of the block. It cleared, but there was barely room for a pair of photons between it and the lip.



Ground down these nubs on the steering rack that were actually contacting the oil pan. It's a crazy close fit.



Cut a good deal of the inside flange of the cowl out of the way to make clearance for the ECU and various other electrical sundries that we're planning on putting up there:



And of course some paint to prevent rust.

 
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aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
It hurt doing this on the empty case. It hurt a lot *more* doing it on the VERY expensive Quaife box.

 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
Got the alternator & belt tensioner setup more or less complete. I just need a correct-length bolt for the engine side rod-end.

I like it SO much more than the original stack-of-washers setup.

I got the water pump housing back from my machinist this afternoon. We ended up mounting the adjustment turnbuckle to an ear of the casting of the housing.
Mounted there, the turnbuckle was about an inch long, so I took about a half inch off of each side on the lathe, and about 1/4" off of each rod end (as they were too long and touching inside the shortened housing).



From there, when fully retracted, the engine-side spherical bearing was running out of angular travel and binding against the casting. I turned up a 3/8" spacer on the lathe, which seems to have cured the angle problem.
(in the photo, it's not bolted to the alternator, but it's got a slight upward angle when bolted up and adjusted)
(yes, I'm going to be replacing that long bolt)

 

aMaff

High Speed Low Drag
Moderator
V
1992 Miata / 2003 Pathfinder
After a week out, it's back in after some fettling, and with an actual clutch and transmission this time. This week it should be buttoned up the rest of the way, then exhaust, wiring and tuning.

 

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