ahhh...I see said the blind man. You're using a 2.5 block?

 

 

 

You have a lot more piston options with the MIDs, I am running J and Es. The MIDs webbing also fill the block at the top of the block so there is no cylinder movement. And the big point is if you have a piston failure you bore and go with a larger piston. If the MIDs are done properly they are a heck of an asset. The pistons are from a previous build I have bored and gone with a larger piston since this photo. The photo is to show the webbing

 

You can dry sleeve the 2.5l block and bore it to 106mm. This was done years ago with good reliability. One Rennlister has about 100k miles on his now street/track. The company that did the sleeves is around LA or San Diego. As I recall it was not that expensive, back then in the $1200-1300 range. I cannot find their contacts I go, as I recall it was "Precision" "forgotten second part of name".

You can also contact LA sleeves and see who they recommend. Darton may also have a list of locals they recommend.
​​​​​​

 

Precision was the company that did the RAGE2 car 2.5 block in Calgary. That's the block that's sitting in my garage right now.....not the 100k mile block that is still running belonging to David Floyd .....see post 21 on my thread. Pics of the 106mm pistons on the link. I suppose I should post some pics of the block. I was impressed with how well the sleeves held up to the destruction of the connecting rod snapping.

https://rennlist.com/forums/944-turb...s-old-car.html

 

side note on alusil, OP is doing a 944/Mitsu hybrid stroker so no off the shelf 944 alusil (wossner) pistons work.
and having wossner make custom ones is a thousand-buck proposition...yikes.

 

 

 

be cool to see results of that.

i think you could get good results shaping the 944 combustion chamber like the 1996-up GM L31 vortec heads, "heart shaped fast burn" style.

search this forum for l31 vortec, i made a comparison thread years ago.