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Discussion Starter #1 (Edited)
So this idea/rant/project is the result of having too many parts and resources laying around:

Let me start off by saying that I run an automotive machine shop, have been for a few years now, and kiiind of know what I'm doing. I've installed dry cylinder sleeves many times, and have the resources and capabilities to make this happen.

The plan:

With a bore spacing of 86mm, I feel confident that I can get sleeves that are just small enough on the inside to be bored back out to 81mm (3/32" wall sleeves are an easy find). This, if you're any good at subtraction, leaves a cylinder wall thickness (on either side) of 2.5mm, or 0.098". Yeah, i know that's pretty darn thin.

Yeah, the sleeves will be (almost) touching each other...and there's a possibility of sleeves shifting...and/or not sealing against the head...but you know what? I can, so I'm gonna! The worst that happens is that i get it all installed and it doesn't work. ooohz noez. It was a trashed block anyways.

The whole reason for doing this...was not for the bump in displacement. Yeah, it'll be a ~1.73L block then...but have you looked at how close the valves are to the cylinder walls? Especially the exhaust valves? Moving the wall out (from 78mm to 81mm) will move the wall 1.5mm away from the valves and either a) give the valves the ability to use more of their full circumference to flow air, or b) allow me to put in bigger valves and seats (that will then be back to the cylinder walls, lol). Thus getting more air in and out of said engine.

Like I said, even it doesn't work, I'm out $100 in sleeves, and about 8 hours of my life. At least at that point it will have been documented (I will take a tonnnn of pictures with dimensions, etc) for the community. That, to me, is worth it.

I'll hopefully have the spare block torn down by this weekend, and I will, of course keep this thread updated as much as possible.

17 AUG 2013 UPDATE:

so....according to http://www.zealautowerks.com/bseries.html:
B16 piston: 81mm, 30mm CH, 6.01cc dome
B16 rod:134mm OL
Miata Crank: 83.5mm
Miata Head: 36cc
Miata HG: 0.040"
Miata Block: 206.5mm height

12.0:1 CR
1721cc
1.6:1 R/S
0.030" piston to deck

obviously theres no telling how the valves are going to go into/around the B16A pistons...

Assuming my numbers are right as far as Miata deck height and stroke are correct, then HOLY **** THIS MIGHT WORK.
 

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Should be sweet.
Are you going to be balancing the rotating assembly? Going with higher compression too, I assume?

I have a feeling that's your best bet as forcing a bunch of air into a very thin cylinder wall probably wouldn't be too good for longevity.
 

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Discussion Starter #8
Should be sweet.
Are you going to be balancing the rotating assembly? Going with higher compression too, I assume?

I have a feeling that's your best bet as forcing a bunch of air into a very thin cylinder wall probably wouldn't be too good for longevity.
i completely agree, and as a result (short answer, 'yes'), im definitely leaning more in the direction of high compression all motor.

and OF COURSE i'll have flow numbers before and after...but lets tackle the block work first, as that'll determine how i reshape the combustion chambers manually.
 

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Discussion Starter #11
And as far as "all motor", you sure as hell picked the wrong base motor/family. :woolery:
i know, right? lol.

and yes, this is simply a case of cheap motors laying around, cheap parts, and free labor. soooo.....why not?
 

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Discussion Starter #13
This should work fine. There's a shop that does this to BPs.


Though... they sleeve theirs.
do you have any info on this, or contact info for said shop?

i am, technically, going to be sleeving it. but just using straight sleeves, which a lot of people just call 'cylinder liners'.
 

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If you could fit a BP4W or BPVE head on it you'd be in business, otherwise you're still stuck with the 1.6 crappy head. Please do it so we have another thread to point people to to show them how terrible the 1.6 is and how pointless it is to work over.
 
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