NB MX-5 Hey, it's Minnie!

I removed the stock steering wheel and tried mocking up the MS hub. It was going to take some modification to get it to clear the clockspring, and to have the Momo wheel mount up in the correct orientation. No free lunch in this case.

Warmer after a few days and I was feeling better so it was out to the garage. Had some work to do on other vehicles first, then it was on to Minnie. Pulled the charge pipes, drained coolant and pulled the radiator. With all the other work I did that was all my back could take for the day (pulled muscles from coughing for two weeks). Since I had my other chores done now I could hit it hard the next day.
 
I decided to take that next day off and give my back a chance to recuperate some more. I did receive my revlimiter horn button for the new steering wheel.

I went back at it. Got everything stripped down to the block in about three hours. It helped a lot having the flex joint in the header, I didn't have to remove it completely as I have had to do in the past with other pieces. I forgot what a PITA it was removing the head, having sore muscles certainly didn't help matters any. Here was how she sat:

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The mail delivered my horn ring (you need one of these if you plan on using a horn button, otherwise the button will rattle around in the center hole). Once I got the engine back together I could get the steering wheel installed.
 
Finally got back to working on the head swap. Went about swapping the exhaust cam over and installing the JDM intake cam. Moved the front coolant tap and the rear thermostat housing (this required clean-up and the use of sealant for the front O-ring and a new factory gasket on the rear). The Allen socket head cap screws I used for the thermostat housing showed signs of rust so I made a trip to Ace and bought some stainless replacements. Here is all that:

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Before I put the head in place I decided to remove the three exhaust manifold studs that I had to replace with longer studs for the supercharger manifold. Two came out with no problem but the last one was a PITA. Kroil was my friend in this. Once I had it out I could see the threads in the head looked stripped. I'll have to go to my local hardware store that carries metric taps and get one to chase the threads with. Couldn't get a picture of this one.

Next I tackled the crap on the pistons. I am not quite sure what this was, possibly oil that appeared to be leaking by the valve seals. I used some BrakeKleen, let that soak in and then hit it with a nylon cleaning wheel on my drill. Here are before and after pictures of that:

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Finally, I had looked at the MS steering wheel hub to see how I could move things around so the Momo wheel would line up properly and allow the turn signal canceling piece to be in the right orientation. It appeared that I could remove the black plastic piece from the hub and reorient it . After some gentle work I was able to do so. Blurry picture of what I am talking about, I will try getting better shots once I get to work on installing the wheel (you are looking at the small black piece in the center):

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Despite it still being chilly, got back out in the garage and moved forward. I neglected to talk about using lubricant when installing the parts on the head. If the cams/lifters aren't lubed, the first start with result in a lot of wear at a minimum. In the past I have used a moly paste, while I was out the other day I looked to see what was available in an parts store and found some Lucas semi-synthetic lube that was a liquid. With the ARP head studs I have you also have to use lubricant, they have their own special formula. When you buy the stud kit they send you a little packet of the stuff, but I went through that and went ahead and bought a can of it. Here is what I am talking about:

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Started off with cleaning things up. First thing done was chasing the threads in the hole for the exhaust manifold stud that fought me during removal with a tap from a set I picked up from Harbor Freight (this one takes a M10 X 1.25). I used BrakeKleen and sprayed down into the stud holes in the block to clean them out. You don't want to leave any liquid inside the holes, you can actually get hydraulic lock when installing the fasteners and they won't seat properly. I use a paper towel that I screw into a taper and insert that to absorb the fluid. Next I finished cleaning up the mating surface of the block using my sanding board. Cleaned all that residue off. Next up was cleaning all the assembly lube off the studs. Again I used BrakeKleen, wiping the studs down with a paper towel. In order to get any crud out of the threads I use a paper towel forced into the thread valley with my thumbnail and then turn the stud. Works great. Next step was to lube the threads and insert the studs into the block. You don't want to glob the lube on but you want to make sure there is an even coat on all the threads. Couldn't really get a good picture, the gray on the threads is what I'm talking about:

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Once the studs are in the block, you will see the forward-most one sticks up a little compared to the others. This is not an issue:

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Got all the studs installed, put the gasket in place double-checking that I had it aligned correctly, lubed the upper threads on the studs then put the head in place. Cleaned up the nuts and washers, then lubed them and put all on. At this point I want to touch on the importance of constantly researching. I came across something about the torque values that ARP gives for the head studs. General consensus is that they are too high. Originally their instructions said torque to 80 lb-ft, now they have dropped that to 65 lb-ft. Factory spec is 56-60 lb-ft. I decided to torqued the new head to 56 lb-ft in three steps. Got that all done without issue.

Whenever you do any work to your car, it's a good idea to take a look around where you are working, even at stuff you aren't touching. When I was disassembling things I found one of the heater hoses was being cut right where the end of the pipe it was attached to ended. Bought a replacement from Mazda and changed that out. You can see from the following pictures how it was being cut. Also, the new hose is slightly different in configuration from the old one (I had changed these hoses since buying the car, but I can't recall where I got them from).

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Put the exhaust manifold in place with a couple of nuts on it finger tight just to keep it from banging around. Finally, while looking things over to make sure I hadn't missed anything, I noticed a couple of big holes in the center of the head that I couldn't recall taking anything out of. Checked the old head and there are two Allen head plugs in those holes:

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I have no idea of the purpose of these, or why the shop that ported the head left them out. My big impact didn't budge either one, so I was plying the threads with Kroil to try and loosen them up.
 
Did a little research on Mazda Motorsports' site, those missing plugs were cheap. Went to the dealer in the morning, cost was less than $4 each. Unfortunately there was only one in the GA location, the remaining stock was in TX and I had to wait a minimum of 5 days for delivery. Oh well, I'd get everything else buttoned up while I waited.
 
Weather was back to being wacky here, too cold to work in the garage. Horn surround for the steering wheel showed up. I liked how it looked. Here are shots of the wheel without and with the surround (that is the horn button I got from revlimiter):

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I had to measure to see the length of the button head screws I would need to use to mount the surround.
 
It got warmer, so back into the garage. Started by checking the clearance on the intake valves, all were very tight. Pulled the cam and measured all the shims. Did the same for the exhaust side. Basically everything was overly tight so I was going to have to get some shims. I figured out what all I needed, went to hit the dealer to get them ordered.
 
Back at it again, got the shims on order first thing in the morning. In the afternoon I decided to start with the steering wheel to see if the hub was going to need any modification beyond moving the turn signal cancel mechanism bushing. Amazingly, I didn't have to do anything else to get it mounted.

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I hadn't rigged up the airbag resistor yet, I needed some smaller StaKons than what I had on hand.

Started putting things back on the engine with the intake side first. Got the manifold and injectors back on. Put the radiator hose on my reroute at the back of the engine. Installed the extended studs for the supercharger mounting bracket and tightened the remaining nuts on the exhaust manifold, only to find out one of the nuts was stripped. I guessed that happened when I was working on getting the stock studs out of those three locations on the new head. So that put a crimp in getting anything else done that day. I would hit Ace the following to see if they had a fine thread metric nut I can use. In the meantime, she was asleep for the night:

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Ace let me down so it was back to the dealer. Gave the guy the part number, he typed it into the computer and then disappeared in the back. When he came back he had the five nuts I asked for in his hand. Best part? He didn't charge me for them. That made my week. Got home and used two of the nuts, that got the exhaust manifold finished. Put the manifold blanket in place and installed the supercharger mounting bracket. That was pretty much it for under the hood, as I wanted to leave myself as much room as possible to get the timing belt back on once the valve lash was set.

Decided to look at what I needed to do in order to connect the horn and driver's airbag resistor. Cut the wire off the factory steering wheel, added some extra length with soldering/heat shrink and then put a disconnect on the end. That should take care of the horn.

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Unfortunately the resistor wouldn't fit into the airbag connector, so I was headed to pick & pull to see if I could find a blown airbag with the connector on it to use as my bypass.
 
Went to the junkyard in the morning. Found several donors but then also discovered I neglected to bring a 10mm socket with me (to remove the airbag). They didn't have any to lend so I shot back home, got the socket and then returned. Donor car was a 1999 Protégé, but there are several choices around that year for the same connectors (that I know of). Got home and commenced to put it all together:

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That gave me a plug and play airbag resistor. I also picked up a horn connector so I could put my stock wheel back to as it was for quick swapping (wish I had thought of this before cutting the horn connector off). Everything was now connected for the wheel, the test will come once I had everything back together and have power on the car. No word on my shims though.
 
Couldn't really do much else, so connected the battery (which was on the charger) to test my steering wheel controls. Horn worked, turn signal cancel worked in both directions and the airbag light went out as normal. I’d have to see once I could drive her if the airbag light will stay out or not, but right then I was happy.
 
Was very pissed off. Did not receive my valve shims in time to get her back together before heading back to work. I stopped by the dealer and they had all of them except for one. Why not call me and let me get what you had? Kind of a moot point anyway as my digital caliper decided to die. So, I put some parts back into the engine bay for protection and then sadly walked away. That was it for another couple of months.
 
Got home and made it in to the dealer on the next Saturday. Guy went right back and got the last shim. Went on vacation but would be posting more the next week so stay tuned...
 
Got home on a Tuesday, took the first day off to rest from our 12 hour drive. I did go to the dealer to order a new undertray, my old one slipped under the garage door while I was closing it a few months previously and got damaged. I started off slow by washing the wife's car. While I was doing that the dealer called to say the undertray was in so once the car wash was done I headed up there to pick it up.

Getting home it was time to dive back in. The exhaust camshaft had some surface rusting, probably as a result of some weird weather before I went back to work. I cleaned that up with a brass wire brush, some non-marring Scotchbrite pads, WD-40 and elbow grease. PSA, if you are going to have your camshafts sitting around for any period of time I would recommend coating them with some sort of preservative like grease.

I had made up a sheet with all the shim measurements when I tore things down, and I couldn't find the damn thing. After some frustrated searching I found I had left it inside the factory manual. With that in hand I started in getting the exhaust cam set up. Put the shims in that I had calculated needing, installed the cam and then checked the clearance. A couple were a little tight but the rest were fine. Next up was the intake cam. I used more of the new shims here, unfortunately they were all tighter than the exhaust cam shims. I was going to go ahead and try running it as is, I didn't really expect any issues.
Once that was done it was install the new cam seals, cam sprockets and then the timing belt. Put back all the little covers for the timing belt, installed the spark plugs then installed the valve cover with a new gasket. All torqued properly of course (it's really hard feeling the in-lb wrench click when it's on a lower setting). Put the accessory belts on and tensioned those. Routed the intake hose where it needed to go, then installed the supercharger. Radiator was next followed by the location cover up top. At that point I decided to call it a day, I needed to reclaim my battery charger from one of my sons so I could get her started the next day. I didn't take any pictures because it's all work I had done before.

Still to go was putting on the lower radiator hose and some fasteners on the bottom, including the new undertray. Front shock brace, cowling cover (I was going to wait on that until after a test drive) and filling the cooling system. Then, test drive!
 
Got back into it. Finished hooking up the radiator and other bits and pieces. Jacked up the front end and put my nifty filling funnel on the radiator. Had to go to the store for some more antifreeze. Once everything was full I went to start her up, only to find that the battery was low. I had it charging on a low amp setting overnight but when I checked it was only at 8.5 volts. Tried starting her anyway using the "Start" setting on my charger with no luck. I went ahead and set the charger for a higher amp setting to see where that would get me. Tried again a little while later, still without success but the battery was up to 11.5 volts without the charger connected. Given the battery is 5 years old and my schedule I figure it is done for, so another battery was ordered. The charger was still connected in case I could get it back up enough to get her started to burp the cooling system.

And for all of those who are visually driven, you have seen pictures of what she looked like stripped so here is one as she sat then:

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After I got the battery and installed it, tried starting her but she didn't want to fire. Gave her some gas and she fired, but sounded like she was running on fewer than 4 cylinders. Pulled the plugs and it looked like only firing on one cylinder. After some downtime while I cogitated, I yanked everything down again to see where I had made a mistake. Checked to make sure I hadn't screwed up on the timing belt or left an electrical connector disconnected but everything checked out. After it was all back together fired her up again with the same result. After some more downtime to beat myself up, I bought a set of feeler gauges that went down to 0.0015 (my other set only went to 0.005) and checked the valve lash. Apparently I am an idiot because all but one of the intake lash clearances were very tight, and the exhaust clearances weren't a whole lot better. I was not sure of the cause of this, my caliper did malfunction but I didn't think to the degree that would have resulted in this. Anyway, with my new digital caliper and feeler gauge I checked everything and figured out what I would need for new shims to fix it. Got those on order and was just waiting on them to show up so I could see if this would correct the problem.
 
Stopped by the dealer on my way to Cars & Coffee in the Camaro to see if the shims had arrived. They had (not sure why I did not receive the promised call) so picked them up. First thing next morning I got busy. Got the shims installed per my last clearance readings, put the cams on and checked them again. There were several off so pulled the cams again and moved things around. Ended up doing this a couple of times but ended up with all the exhaust clearances in spec, and only a couple of the intake clearances off by a little. Assembled everything, turned the key and she basically started right up. Let her run for a bit to warm up, then hoisted the front into the air and ran her some more to make sure all the air was out of the coolant system. At that point everything was back together, unfortunately it was raining so I wasn’t going to do any test drive until the next day.

Takeaway from this is to triple check your valve lash and make sure you have a set of feeler gauges that go nearly to zero.
 
Got up in the morning and despite the threat of rain, pulled her out to give her a bath (first one since September some time). She cleaned up well. Piddled around and checked the normal things (tire pressure, oil/coolant levels etc) once that was done. Just got finished up and sat down to post this, looked outside and the rain was pouring down. It looked like no test drive that day either. :cry2:
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Weather cleared a bit and the roads were dry, so I took her out for a short test. Drove fine, did notice some stuttering at higher engine speeds so I'm going to check and see if any water got into the spark plug wells when I washed her. The new steering wheel feels great, and no airbag light came on. It feels so different from the wife's Camaro which I expected, but I prefer this. Yes, it's hard to argue with a honking-big American V8, but the Miata is so tossable that there is no comparison handling-wise. I can feel the road and it is so much more responsive (some of that is due to the front negative camber I know). It is just a much better balanced package overall, and for my tastes more enjoyable.
 
Had to take two days off while doing a head gasket job on one of the kids' cars. In the morning I pulled the COPS, three of the plug recesses had water in them. Looks like I need to take even more care when I wash down the engine bay. Blew that out with compressed air, initial shot didn't get it all so I put a paper towel into the hole and then blew it again. Left everything open for a while to make sure it was all dry. Also noticed the 'charger belt had walked off one tooth so put that back in place, will monitor to see if I need to adjust the 'charger position.

Then, since it was a nice day, I went for a drive. Took my favorite local backroad. It's amazing the difference between this and my wife's Camaro. Weight does have an impact on handling, if you doubt that then take a modern car with the latest suspension and drive it back to back with an older well-sorted sports car. With the water cleared out of the plug holes she pulled hard to redline. Even small throttle openings provided a push of effortless acceleration. It's sneaky fast compared to the sledgehammer speed of the Camaro's V8. I love this car.
 
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