KMiata SCCA Solo XP swap

aMaff

High Speed Low Drag
:
1992 Miata / 2003 Pathfinder
It's finally getting close enough that I want to get started on prep work for this project since I've got most of the parts needed now.

The first bit of prep was the steering rack, and so as to not lose the NB rack bolts I figured I'd put the bolts into the threaded holes in the V8R-sourced subframe.
3 out of 4 had powder coat completely boogering the bolt holes. On the upside, the thread pitch of those holes is M12x1.25mm, which is the M12 tap I don't actually have in stock.
A quick Amazon shopping trip and a couple days later, the tap comes in.
After chasing the threads in the good bolt hole and 2 of the 3 bad ones, I realize 1 of the engine mount brackets completely blocks access to the 4th. Improvise and overcome right?

Turns out, a 5/16" 12-point socket makes a good-enough narrow access tap wrench for an M12 tap.



Nickolaus G recommended I check the rest of the holes on the subframe, and sure enough, the news is equally "good".

Nope.


Nope.


Nope.


Nope.


Nope.


Next move is to run to home depot to get some 3/8 rod (since I'm apparently out) to make a bore-polishing sanpaper flap tool to clean these out before I try bolting this whole thing to the car. Probably need to clean up the surfaces where the eccentric washers bear on the subframe as the powdercoat is probably way too thick there and might limit adjustment range. I'll re-paint everything to prevent rust, but it'll be a lot thinner than whatever 1/8" of powdercoat they slapped on this thing with no protection on bolt holes....
 
SITREP:
Good news: I got the bores cleared out.
Bad news: they're banana shaped and the bolts won't go in.



The bolts bind up solid as soon as they get to the 2nd weld, so it's super warped :(
I could bash it in with a hammer, but that's going to lead to some serious suspension bind. And I don't have a 15mm reamer sitting around (and a mill big enough to fixture this damn thing in) to fix it myself.




I appear to have been the very unlucky person that got a bum part. David with KMiata has been awesome to work with and has been super apologetic. He says he's only seen one of these in the last 2 years once the production kits started going out, and they're going to get another one sent out ASAP. Super frustrating, but I'm glad to be finding it now rather than in a couple months when I'm starting in earnest.
 
Good news: KMiata is having another subframe sent out today.



While I wait for that to come in, I figure I might as well do some of the small things. I have a depowered NB rack as specced out for the subframe mounts, but didn't realize (until reading through the full documentation) that the 2 small hydraulic fittings on the main tube of the rack housing need to be cut off. So, I did that, then picked up a couple small 3/16" rivets to JBWeld in





Once it sets up I'll clean that up & throw some paint on it.
 
(rlaugh)
Still no. Timetable's always been to tear it down to start this properly *AFTER* the hill climb in August. I'm just starting to work on some of the finnicky out-of-the-car stuff while I'm here. Probably going to tackle the oil pump / chain tensioner / sump / oil pickup next, but that's a big enough job I keep kicking it down the road. It's not really THAT big, I just haven't been able to string a day together to do it.
 
(rlaugh)
Still no. Timetable's always been to tear it down to start this properly *AFTER* the hill climb in August. I'm just starting to work on some of the finnicky out-of-the-car stuff while I'm here. Probably going to tackle the oil pump / chain tensioner / sump / oil pickup next, but that's a big enough job I keep kicking it down the road. It's not really THAT big, I just haven't been able to string a day together to do it.

Ok, got it! Which one are you doing again?
 
Which hill climb? Chasing the Dragon in Robbinsville, NC
 
The Duryea Hill Climb (or maybe Pagoda?) in PA is, I think, either the same weekend or 1 weekend either side of Chasing the Dragon. I'd love to make it out to some PHA events sometime, they seem to put on a great show.
 
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Finally broke the seal on the motor.

And despite having drained it, completely I thought, after first getting it...



Maybe there was a bunch stored inside that massive oil pump, that after flipping it over a couple times for various reasons, broke free? I dunno, but I didn't think I needed to drain the sump a second time. I'm REALLY glad I had that pan there or I'd have been boned.
Thankfully I managed to get most of it into a drain pan without issue. Only a minor spill, all things considered.



The bolts for the oil pan are SUPER crusty, so I may need to pick up a package of those if they don't clean up in the parts washer, and are actually corroded too badly
 
Got the engine torn down as far as I need to:



Including the mahoosive oil-pump & counter-balance shaft assembly. That thing is...not light.




Now to spend a lot of quality time cleaning HondaBond and oil off of parts and reassembling things.

 
I also realized that the engine I got from the scrapper didn't come with the water pump housing. Or rather, I realized, looking at the shape of the new water pump, and the shape of the whacking great big hole on the side of the engine, that there was at least 1 piece missing (rlaugh)
Did a little looking around and realized that, yeah, there's an intermediate housing there that the pump and thermostat bolt to.

I'm learning new things every day!
 
The new subframe came in on Friday as I was leaving to spend the weekend at the lake w/ the family, so no checking got done, but:

No hammer or clearanceing needed!



A couple of the threaded holes needed the threads chased, and some of the lower control arm bolts are a hair tight (that'll just be a matter of cleaning a bit of powder coat). But that the upper arm bolts just fit is huge (and confirmation, if more was needed, that there was an issue).
 
I've got the oil pump swapped. RSX TypeS pump (compare it to the stock TSX monstrosity in my previous post):



KMiata's billet oil pump housing to work with their oil pickup (to go over the steering rack). The stock TypeS pump pickup sticks straight back, which would go through the steering rack:



Once I get the seal & gasket set in, I'll crack into the honda bond (needed for the 'oil squirter plug" bolt) and get the oil pan, water pump housing and timing covers back on. I'll need to grab a buddy this weekend to hold a wrench so I can torque the 50 degree intake pulley (vs the stock TSX 25 degree VVT pulley) onto the cam.
 
Steering rack's ready to go (minus a couple zip ties to secure the boots).
New inner tie rods, new R Package outer tie rods, and my home-brew steering limiters.

 
I thought I was done with the rack, until I had one of those "oh s***, you dumbass" realizations while drifting off to sleep last night.

There is a shoulder on the new style Inner Tie Rod locking washers that goes on the OD of the rack, vs the old style washers that sat on the OD of the tie rod's threads.
I realized the rack limiters I made are a really snug fit on the rack, and might not clear the washer. I pulled the boots off and turned the rack through its full range of motion and sure enough, I'd managed to reduce the total travel by another 1/4 turn or so (1/8" per side, give or take).



I threw it in the lathe and put a counter-bore in it to clear the washer on 1 side, but still ride nice and snug on the rack:



Much mo' better.




Of course, taking those staked on washers off broke the areas that were staked, so I clocked them 90 degrees and had 2 fresh areas on the shoulder to put new stakes in. Those plus red loctite (again... removing the inner tie rods wasn't fun) should be good to go now.
 
Not KMiata content as much as XP content, but these are currently being CNC'd :D

 
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