STS Miata - Project: Stronger Faster Lighter

Ok, so I thought something looked funny in the picture of the oil pump. If you look closely, the oil seal isn't exactly... sealed. So I went ahead and ran downstairs for a second and grabbed the original one. Here's the fitment on that:
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Note the snug fit of the oil seal on the crank.

Here's a closeup of how the 'new' pump sits:
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That would be, to say the least, a bit messy. Mazda Motorsports sent me the oil pump for a 1992 "big nose" crank engine instead of a 1991.5 "long nose" crank like I requested when I called in the order. Grrrrrrr. Looks like I'm going to be sitting on hold for a while tomorrow... fortunately I should have the guy's direct extension so I can call him and get this sorted quickly (hopefully)

In conclusion, there's always a silver lining. Had I not broken that bolt, I would have had to take off the oil pan (if I even noticed it) after the RTV had set, and been a whole nother pain in the balls. *sigh* at least it's starting to LOOK like an engine...

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nice job, andrew! i want to build an engine!!!

Dooo eeeet!



I called Mazda Motorsports and got everything straightened out. They're sending a new oil pump and while I was there I ordered a water pump b/c they're pretty cheap and will mean I can get the entire engine together while the old one's still in the car, (and gave me a discount on everything) and are over-nighting me the parts for free. And to return the oil pump I get to use Mazdaspeed's fed-ex account. So... awesome! I'll be getting new bolts for the oil pan from Kevin on Thursday, and with any luck I can get this thing buttoned up this weekend or early next week. After that I'm going to have to wait for a couple other things to fall into place, but the engine should be going in here soon. Shweet! The only things I'll need to scavenge from the old drive-train will be the clutch assembly, the starter, the block end plate, the bolts for the trans and I think the shifter.
 
nice, sweet catch on the oil pump...good thing too.

The dude goes "yes, you have a 1992 and that oil pump is for a 1992". "Yeah, but the engine's from a 1991 with the long nose crank" "Well, if it's for a different car, you need to have that updated on the website." "No... it's for the same car, just a different engine, like I said when I ordered it!" (doughpoke

Anyway, once he wrapped his mind around an engine from one year model car going into the body from another, he got everything straightened out for me. I hope.
 
Dude sounds bright. Good luck with that.

BTW, is that technically legal? The '92 didn't come with the longnose, and the superceded part is the 92+ motor.
 
I don't think it's an issue. It's a 1.6L miata motor. Internally, they're completely identical. If I were going from a 1.8 to a 1.6, or vice versa, sure, there'd be issues. But for all intents and purposes a B6 is a B6.
 
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Yeah, I don't think it's a problem, but I think if you were protested you might lose. It'd be the mother of all weenie protests, but technically I'd think you've got an illegal engine.
 
Worst case I swap the crank over from my current engine to the new one. I've already got the oil pump and front main seal for it, and really that's the only difference. I'm not really worried about it, it'll just take a little more time before I can get this engine operational. I'm looking to get a rules clarification from those more knowledgeable than I, both here, and on M.net (there's a thread in the Performance Driving section I just put up).
 
Yeah, I don't think it's a problem, but I think if you were protested you might lose. It'd be the mother of all weenie protests, but technically I'd think you've got an illegal engine.
I think that just to be sure, he should give it to someone who has a long-nose engine. :D
 
Exactly what crankshaft do you have?

Short Nose - 1990-1991
Big Nose - 1991.5-1993
Long Nose - Service part for Short nose crankshaft not sure if it was installed from the factory in any engines.

The long nose and short nose use the same oil pump while the big nose uses a different one.
 
I have a long nose that I'm building, and the engine IN the car has a big nose.

My understanding is:
Short Nose - 1990-1991.5
Long Nose - 1991.5-1992 and service item for failed short nose
Big Nose - 1992-1993
 
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I have a long nose that I'm building, and the engine IN the car has a big nose.

My understanding is:
Short Nose - 1990-1991.5
Long Nose - 1991.5-1992 and service item for failed short nose
Big Nose - 1992-1993

I can not find anything to support your understanding. Every part I see for the crank changes at VIN 209447 in 1991 (seal, UD pulley).

See http://www.miata.net/garage/crankshaft.html for details on the cranks. I might have a big nose crank (need to check but IIRC my UD pulley did not fit) in my spare engine if you know anybody heading down your way soon and you want to trade.
 
Even if I'm wrong, the question remains: does it matter?

If you'd be willing to ship it to me, see if you can get a quote and I'll pay you over paypal.

FWIW, I just checked my parts guide and it looks like there are only 2 in there, so I'm not sure, you may be correct. Though I remember reading in more than one place that when mazda realized the fault they started implimenting the long nose in a short run of cars before the big nose came out...
 
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Maybe? Technically that would be an illegal configuration for your car since it could not have come with a LN crank. How much if any difference does a LN Vs BN make? Do they weigh the same?

Let me check and see what I have (and I need to pull it from the engine)

Not sure if they put the long nose in any cars or not. But since the long nose uses the same oil pump and front crank seal as the short nose it would have been before the 91.5 VIN 209447 switchover.
 
yeah. Ok, let me know. My parts guy locally sold all his 1.6 blocks here recently to another vendor. I think I can get one from the Parts Group, but they want $170 + shipping. If I have to go that route I will, but I'd imagine shipping one b/w DC and ATL would be cheaper.

Worst case is I pull my old motor apart after it comes out of the engine and pull the crank from it, but that's a ways off.
 
Muff, I should have a BNC in the basement if you're interested. Even swap.
 
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