Anyone know any pistons that are around 80 to 81.5mm that have a CH of lower than the stock miata 1.6 pistons and have wrist pin around 20mm?

Looking at a overbore of maybe 3.5mm

 

You must be planning to sleeve the block, yes?

 

No and I don't think you can sleeve the block

 

You can actually.

 

Well I don't see sleveing the block is gonna help me out anyways, but if someone does I am all ears.

 

I don't see why you wouldn't be able to sleeve the block.

 

What are you gonna gain with sleeving the block?

 

I'd like to know too, I'm just saying the block CAN be sleeved.

 

how? I didn't see anything that could be pressed out, maybe bore it out and put a sleeve into it.

 

I think that's what he meant.

 

thats all I could think of, but no looking at taking out .120 to .140 out of it. Don't see how sleeves will help with that much removed if you could even sleeve that afterwards.

 

This is what I read about boring and sleeving a 1.8 to bump up the displacement to 2 liters. Not sure if they do 1.6 motors too though.

http://www.mccullyracingmotors.com/i...s/Page1100.htm

 

That's how they did it at the factory when the engine was originally manufactured.


I don't believe I've ever seen an off-the-shelf piston larger than 79.5mm for the 1.6l engine, though either Wiseco or JE will custom-manufacture a piston to damn near any spec you could want.

I guess the big question would be why? Good 1.8l blocks are a dime a dozen, and there are plenty of lower-than-stock-CR pistons available for them.

 

yeah thats why I'm not looking at the off the self pistons for b6
Looking though various other oem pistons, hondas, audis, etc

 

http://www.sdsefi.com/features/july03miata.htm

http://www.atomicspeedware.com/4agez...pratio861.aspx

 

I am a 1.6 purist and will fight for them!


Wiseco makes off the shelf .060 over pistons, 79.5mm bore

If you need bigger than that, you might as well get a built 1.8 or 2.0

http://www.nolimitmotorsport.com/prod/K554M795

 

I mentioned sleeving because at 81.5mm you will very likely be in the water jacket. But if you have it sleeved you can typically go much larger than the standard overbores because sleeves are thicker and will have a consistent thickness unlike a 20 year old cast block of rusty iron. And yes, it can be done and is a common procedure.

 

There is no way you'll be able to get an overbore that big without warping your cylinder walls, they will be way to thin, or like said above you'll be in the water jackets. If you want to go that big you might as well get a 1.8.

Sleeving is expensive, and not common practice on our motors due to them being iron. I am not sure what you're going to get out of it anyways, any of your goals and dreams can be done with .60 over like I have.

 

FULLY agree with these guys... Overbore too much and you will either break into water jackets or it will be so freakin thin that even street driving youde risk overheating the metal near the jackets to the point it will either warp or burn through completly, let alone be able to hold boost/power... Thats why instead of just boring out the 1.6 Mazda created the BP 1.8 block. They HAD to stretch it out a bit to get enough meat between the cylinders that problems wouldnt come up. Sleeving the block, while possible, I wouldnt reccomend just because of how much $$$$ would be involved. Get a BP and call it a day.

 

Why not just get a 1.8? I got offered one for free the other day.