| MIATA BUILD |
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 | |  | April 17, 2007 - The engine is going to have to come apart again.
I'm still trying to sort out why, but the pistons are standing proud of the block. Not good. Usually I'd do a quick check of this after installing the first piston, but this was the third engine built with pistons from this batch so I was pretty confident everything was good.
Well, it was supposed to have been built with known pistons. A check of the paperwork indicates that an experimental set of pistons intended for use with a stock crank may have ended up in the motor. I need to do some more checking on this.
Whatever the reason, it appears I'll be tearing it all apart again. At least I know the clearances are good now. Sigh.
entry 131 - tags: engine | | | April 18, 2007 - Much rejoicing!
The engine still has to come apart, but the correct pistons have surfaced. After combing through old paperwork to ensure they did in fact exist, the pistons were found in a dusty box inside another dusty box in the back corner of the FM shop. How they got there is a bit of a mystery, but the end result is that I just need to pull the oil pan off (yuk, lots of silicone sealant involved), pop the rods and pistons out then swap the pistons over. The bore is the same and Wiseco is very accurate on boring. The rings are the same as well, so all the difficult and tedious work does not need to be repeated.
Phew! This is a relief. The pistons that are currently in the block are a unique set, intended to combine the long stroker rods with a stock crank in order to obtain a very good rod ratio. The pistons that I'm supposed to have use the same rods but with a different crank. There's only one set of those in existence as well - so it would have been a long wait if I'd had to have another set made.
entry 132 - tags: engine | | | April 18, 2007 - A request for the RSS readers.
I know there are a few people out there using the RSS feed to watch the site. I'm doing a bit of an experiment - please check out an updated feed at http://targamiata.com/rssplus.php and let me know what you think. I'm new at this RSS stuff.
entry 133 - tags: announcements | | |  | April 19, 2007 - Time to change out the pistons.
The new ones have a much shorter crown on them for some reason. They were supposed to be the same compression ratio, I'm not sure why there's such a difference.
entry 134 - tags: engine | | |  | April 19, 2007 - One good side effect of the piston swap (other than the fact that the new ones won't slam into the head) is that while the pan was off, Bill found a 2001 version ready to install.
Just in time, too - I already had the sealant on the windage tray. So the main bearing support plate went on. Woohoo!
entry 135 - tags: engine, interchange | | |  | April 19, 2007 - The oil pan is sealed with a big bead of black silicone.
It's a little unnerving, because if you don't get it all sealed then you get the pleasure of pulling the engine out again. Yuk.
This silicone is "The Right Stuff", the favorite at Flyin' Miata. The black color also looks more professional than orange or grey, as it unavoidably squeezes out of the seams.
entry 136 - tags: engine | | |  | April 19, 2007 - The head is here and ready to install.
The machine shop did the usual excellent work on the combustion chambers, unshrouding the oversize valves and polishing everything.
entry 137 - tags: engine | | |  | April 19, 2007 - Both the intake and exhaust ports have been massaged for extra flow.
This should be about as good as a Miata head gets.
entry 138 - tags: engine | | |  | April 19, 2007 - With the short block all done, it's time to put a head on.
We're using ARP studs to keep everything together.
entry 139 - tags: engine | | |  | April 19, 2007 - A little gotcha built into the Miata engine.
This is the oil feed for the head. If you put the head gasket on upside down, everything works just fine - other than the fact that you cover up the oil feed. Then you starve your head of oil and it's time to take it all apart again. I've talked to two people recently who have done this. It's an easy mistake to make with expensive consequences - a bad combination.
entry 140 - tags: engine, tips | | |  | April 19, 2007 - If you really want to make an engine look beautiful, you need a bead blasting cabinet.
These are well-experienced parts, but a minute in the blaster and they look as good as new. It's great for cleaning old gasket goo off as well.
entry 141 - tags: engine, tips | | |  | April 19, 2007 - I'm going to run adjustable cam gears so I can dial in the cams.
These particular cams were designed by a friend who works at Integral Powertrain after also working at Cosworth. I have high hopes for them.
Those who know the Flyin' Miata catalog will notice that these are not FM cam gears. Why not? Because these AEMs were kicking around the shop and needed a new home, and this way we don't need new parts. Besides, these particular cam gears have a long history of competition. They were part of the monstrous Track Dog race car I built a few years back, and also visited Car and Driver as part of the original Superfour Challenge. So it's time they had another outing.
The downside is that they're not marked correctly - the gears are actually in the stock positions now, even though the intake cam appears to be retarded by 5 degrees and the exhaust by 4.
entry 142 - tags: engine | | |  | April 19, 2007 - A cam angle sensor?
Yes indeed. This engine is going to have an interesting mix of components. For the engine management, I'm using a Hydra Nemesis. It's going to use a crank trigger wheel as the primary sensor for engine position. But in order to run sequential injection, it needs a second sensor on the camshaft in order to determine which cylinder is ready to fire. On a stock 1999-05 Miata, this sensor is on the front of the intake cam gear. But then I wouldn't be able to run my adjustable gears. So the venerable cam angle sensor from an early car (a 1990 in this case) will be attached to the back of the exhaust cam.
So the engine has a 2001-05 MBSP and oil pan, a 1999-00 block and head, 1990-93 cam angle sensor, hydraulic lifters from a 1990-97, valve keepers from a 1999-05, oil pressure senders from both a 1990 and a 1995, cams originally designed for a 1994-97, a 1994-97 valve cover, 1994 coils, a 1999-05 starter, 1994-97 alternator...thank you Mazda for leaving us this many options!
entry 143 - tags: interchange, engine | | |  | April 22, 2007 - This odd little doodad is an oil cooler.
It sits under the oil filter and coolant runs through it. I don't really see how effective it can be given the relative temperatures of oil and coolant - unless it's intended to get the oil up to temperature more quickly. Regardless, I'll install it if only to act as a spacer. If I install a real oil cooler running through a thermostat, I need this thing to make sure all the fittings clear various protrusions on the block.
My apologies for the picture quality. I forgot the real camera so this is from a camera phone.
entry 144 - tags: engine, interchange | | |  | April 22, 2007 - The 1995-05 Miatas had a "fake" oil pressure gauge that basically just showed that there was at least 7 psi of pressure - that's the little sender here.
The 1990-94 Miatas had a more traditional oil pressure gauge that showed actual oil pressure - that's the big grey sender. I want to run both. A real pressure gauge to tell me how things are going, and a big bright turn the engine off NOW! light.
Another camera phone picture, sorry.
entry 145 - tags: engine, interchange, wiring | | |  | April 22, 2007 - I may not have been busy taking pictures, but I have been busy assembling.
The engine is about 97% complete in this picture, and is even closer in real life. It's not as pretty as in earlier shots, partly because of the camera phone and also because I've been taking shortcuts. Shortcuts, you gasp! Ah, but there is method to my madness.
See, the final engine will have a special valve cover. It's off being powdercoated right now, so I stuck a fairly ugly valve cover in place to protect things. I'm also planning to use individual throttle bodies, so again a junkyard intake manifold was pressed into service. It'll look sexier when I'm done, honest.
Meanwhile, I'm getting close to being able to install the engine. I want to make sure I'm not blocking access to something important first, and I'll spend an evening ensuring the chassis is ready. But it's almost time!
entry 146 - tags: engine | | |  | April 24, 2007 - Time to take the engine from the Flyin' Miata shop to my garage, where the car is being built.
Putting this in the back of my old pickup increases the value of the truck by a factor of 5 at least.
The chassis is almost ready for the engine. I need to plug a few extraneous holes (such as the heater and AC pass-throughs) and then it's time to drop the engine in.
entry 147 - tags: engine, other cars | | |  | April 24, 2007 - A donation from Jason on the Grassroots Motorsports forum - a Sparco navigator footrest.
It reeks of obsession. Not only are the hinge screws countersunk, all of the lightening holes are chamfered and of course there's an engraved Sparco logo on top. Beautifully made for what is really just a metal plate. But it's going to be a good rest for Eric's pretty little feet and it saves me the effort of fabricating one. Thanks Jason!
entry 148 - tags: ergonomics, sponsors | | |  | April 25, 2007 - Time to bolt up the flywheel.
Lots of people have questions about how to keep the crank from turning when tightening the front crank bolt or the flywheel bolts. A well-placed prybar does the trick.
But really, the reason I took this picture was to show off the very cool purple flywheel from Flyin' Miata.
entry 149 - tags: engine | | |  | April 25, 2007 - Most people use a plastic clutch alignment tool to ensure the clutch and pilot bearing are properly aligned.
Bah, that's for sissies. At Flyin' Miata, they use the input shaft from a transmission!
So, the clutch is bolted up and the engine is ready to install. That will hopefully happen tonight and then I'll start the process of firing it up. I want it to make noise this weekend.
entry 150 - tags: engine | | |
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