CP Pistons
 

Anyone have an opinion on these vs. Supertech or Wiseco for a 300-350whp 1.8 build?

CP is a very reputable manufacturer. No personal experience but they are being used in some of the most powerful 4cyl engines around.

Any reason why they aren't so prevalent in the miata community, relative to the others I mentioned above?

Supertech are cheap, dont have piston slap, and are more than strong enough for any reasonable miata build, thats why they're the most popular.

Yeah for low power street application go with the supertechs.

"Low power" I like how your definition of low power is like huge and massive to every other miata owner. Like shit how many 500hp miatas are out there with the BP engine in them? And you call it low power.

600whp

"low power" bro'z

I hold CP pistons in the highest regards. I would not hesitate to run them in a Miata. The only downside I see is limited CR available.

So anything under 500whp, then? Do you know what the strength difference is between a 2618 and a 4032 piston?

The guy who built my engine LOVES the CPs.

When I mentioned that I was thinking about Wiseco pistons he suggested CPs instead since there's less work required to balance them (ie. they come pretty damn good straight out of the box).

Unfortunately the compression ratios are limited compared to Supertech's range.

I know enough to pick 4032 each time :)

I have CP pistons in my build. No issues.

https://www.miataturbo.net/attachmen...d-dscf0195-jpg

On my next motor build I would like to run some custom CP pistons. They are reasonable to work with for custom piston work. Since they have a 9:1 piston I would just modify the dome to fit my CR needs and verify the ring lands are set for the ring package I would want to run.

That being said it makes more $$$ sense to buy some Supertechs. They are more than strong enough for my needs and have great CR options. They are holding strong at my current 297whp.

I put CP's in my mini when i melted a stocker 3 years ago. Absolutely no issues at all. Im only right around 300hp give or take, but everything has gone smooth from install, to break in, to daily driving. And the company is very easy to work with, i was sent the wrong pistons at first, but they fixed that issue with the quickness. lol
oh.... and they gave me lots of stickers.... stickers are good.... a company isnt shit without stickers... :P jk

How do these new pistons on the block compare wrt the supposed weak point of Supertechs?:
https://www.miataturbo.net/engine-pe...32/#post443437

https://www.miataturbo.net/attachmen...s-piston-1-jpg

My engine builder ground down those narrow parts on my Supertechs between the valve reliefs and the edge of the pistons because they were an obvious hot spot otherwise.

So does Mazda on the factory pistons.

I'm rocking CP pistons here, do track events, no issues except it can be a bit noisy on cold startup as mentioned above. Because racecar.

The answer is Supertech, but my JEs are dead quiet.