Hey All - I picked up a new stray with a body/top in fantastic shape, but the drivetrain in terrible shape. And yes, I know, those wheels! Though ironically they're "perfect" for the exocet 15x9 0-offset.
The chassis and presumably the engine have 245k on them. I plan on replacing pretty much everything. I have a big nose crank 1.6 that I have from my exocet before I threw a JDM 1.6 in it. I was seeing blue smoke and low oil pressure at higher RPMs before I pulled it, but it was still running pretty well. I was going to start stripping it down and try to gauage rebuild/replace.
What's the mental math for deciding exactly how much needs rebuilt? I know to look at bearings/cylinders to check for wear (though honestly not really sure what I'm looking for besides this doesn't look like the others?). Is there an easy way to decide if it needs new rings besides cylinder wall scoring? This isn't going to be a race car and I wanted to keep it relatively "cheap," but definitely don't want to be pulling the motor right after I get it in.
Anyone been down this path before? How'd you decide what should stay and what should go?
Can you do a compression or leakdown test? At 245k, if I was in the engine at all, I'd be assuming it wants rings. All you need to do is pop the head off.
In reply to Keith Tanner :
I'm not sure of the miles on the engine I have that came out of the exocet - the one going back into the Miata. The short nosed crank that came with this car is already out. I'll start a build thread with some pictures of the carnage, I'm fairly certain I'm going to avoid rebuilding it even if it means getting another engine (don't want to deal with a short nosed crank that old). So I don't think I can do a compression check with the engines out.
All you need for a compression test is a starter and a battery. Don't even need that for a leakdown.
But either way, I'd be doing rings.
In reply to Keith Tanner :
Huh - you mean out of engine bay you can still do it ? .... I assumed it would violently flop over?
Rodan
Dork
12/19/19 11:35 a.m.
For the cost and hassle of rebuilding/refreshing a 1.6, I would seriously consider swapping in a 1.8...
If you can't find one locally, there's an outfit out of the UK with some great deals on used engines, shipped to your door in the US...
1.8 Engines shipped to your door
No affiliation, but I bought a 6 speed Miata trans from these folks last month... great price, 8 days to my door in AZ. Installed it last week and works perfectly.
They also have a lot of other salvage Miata parts at really competitive prices, even with shipping.
In reply to Rodan :
How much was freight for you ?
*edit: Ah, those prices include freight....
I messaged them about the VVT engine - those are much cheaper than the other ones I'd been looking at. A possibility for sure. I have a 6 speed with short shifter. I need to get a new clutch and flywheel, soft parts, a radiator, driveshaft, ppf (long story), and the rest of the odds and ins.
Well that was easy - 1.8 VVT motor ordered. I'm going to see about getting it running in the chassis and then look at swapping the ECU/enabling a standalone VVT controller.
Rodan
Dork
12/19/19 1:53 p.m.
You'll want to bookmark this: MT.net VVT into NA chassis thread
BTW, you're going to LOVE the end result. 
measure everything.
There is a dial gauge to measure cylinder wear.
In reply to Rodan :
Thanks! Now I just have to let the wallet recover and put in a big Flyin Miata order...
I've always been told to check compression hot and with the throttle wide open. They did it cold and I didn't see them open the throttle- they may have off-camera.
On a very healthy engine, it probably doesn't matter that much, but on a worn engine it could mean the difference between install or rebuild.
I've done more than one cheap rebuild on Datsun motors over the years:
if there is nothing visible wrong in the bore I simply slap new rings in it and replace the rod bearings (you have to take the rods off the crank so might as well slap fresh rod bearings in it). I don't bother with the main bearings.
I try to get away with valve cover, oil pan and head gaskets. Doing this keeps the parts bill to around $100-$120 and can be done in 5-6 hours including yanking the motor.
It's far less than ideal but stops them from smoking.
Thanks for all the feedback guys! Look what arrived today.
