NA build
 

Weird, I made this thread last night, must of forgotten to hit post.

I'm building now my 2nd engine from Curly's Shade Tree Garage, it's a '96 1.8 with an exintake swap, m-tuned reroute, '99 head/intake/VICS, crank scraper, oil pan baffle, RB header, Shogun exhaust, and some pistons we haven't decided on yet. I have a couple questions for y'all.

First off, the owner (Scott) is planning on buying new pistons. What's the best year (aka highest compression ratio) to get? My knowledge is sadly all in 1.6s. There's some rumor of 10.5:1 pistons, but "JDM" model only?

Yes I know VVT > VICs, but he had a '99 head laying around, so we're using it. For the swap, its still going to be DEQ compliant, correct? Stupid OBDII. We're using his '96 EGR valve, looks like it should bolt right up.

Also, WTF is this shit? I'm used to black carbon, but I've never seen this white stuff. Scott says 100 freeway miles equaled about a quart of oil.

https://www.miataturbo.net/attachmen...ine=1364223712

Any guess on what this combo might make on a dyno? Unfortunately it'll be the stock ECU for now, we don't feel like diving into a parallel MS install right now.

That is crap that you need to thoroughly clean off lol

As for pistons, usdm highest is 10:1 on the 01+ bp's, or you can try to find some JDM 10.5:1 pistons. Those are the "best" for n/a while sticking with oem.

Everything else not that much different from what you're used to doing. After all, the overall block design is same, with just a much much better flowing head from your 1.6

I don't see why it wouldn't be smog compliant with what you described. Obviously depending on how strict your area is

Yeah, it's on the '96 head we're not using anyways.

It's the head swap and pistons stuff I'm not aware of, I've built one other stock '94 1.8.

Tail pipe sniffer test isn't too strict AFAIK, it's whether or not it'll throw any codes.

Why would it throw codes if you hook everything up properly?

I've done a couple weird combinations of 10:1 block + 99 head and 9.5:1 block + 01 head before both of which passed our strict Nazi-CA emissions fwiw

That sounds like my motor except I'm using a ported '96 head with oversize valves, using '02 pistons (10:1).

It will pass emissions fine as long as you keep all your emissions gear. The problem will be that the '96 computer runs lean stock and after all that work it will be even leaner, like 15:1+ at WOT.

I'm not too worried about it, we're changing the compression ratio by .5, the stock ecu should be able to compensate for most of it. I'm not worried about .3 AFR points in an NA engine anyways.

It's gotta be better than the smoke screen he was living with before.

https://www.miataturbo.net/attachmen...ine=1364312538

wowww hahahaha

Looks like my old neighbora car when he Seafoamed it. Lol

If you don't mind me asking; what was causing all of the James Bond smoke?

We're not 100% sure. The oil consumption was high, and so far I've found the typical missing AC bolt and a pretty gouged up seal surface on the crank.
https://www.miataturbo.net/attachmen...ine=1364689697
https://www.miataturbo.net/attachmen...ine=1364689697

Neither of these however, would cause the smoke screen. The head was done ~70,000 miles ago, and the smoking happened before and after. The cross hatch is still visible on the cylinder walls, and no rings were broken. So I'm guessing it was still the head, despite the rebuild. '99 head is now rebuilt and ready to go in.

https://www.miataturbo.net/attachmen...ine=1364689697

Wow. Because I had the valve stem seals replaced a few months ago and it still smokes a lot like that too. I checked it on Saturday and cylinder #4 was a kiddy pool of clean oil.

I actually thought it might be a belt sanded head, but it has a nice finish, I'm still at a bit of a loss. Oh well, I'm glad the heads being completely replaced.

I won't do much of a build thread here, as the owner's only on CR, but the crank is getting sleeved for the front seal, and all the parts are out to be cleaned. Blocks being checked for flatness, and ball honed.