LOL, I'm not saying anything.

I just referred you to the posts in the thread that already answered the questions you were asking.

You said "nice build", indicating that you had read the thread....?

T

 

Are those custom JE pistons 4032 or 2618 alloy,and do you always prefer iron liners over alusil cylinders ?

 

A reasonable question, really, since without before and after flow tests, there's no obvious confidence/proof of improvement. We specialize in cylinder heads and over the years I've done a ton of 944 2V and 4V. Early on I wore out our SuperFlow 600 flow bench. It helped develop an excellent shape for the ports, and also helped select the ideal cutters for seat and valve angles (very important, BTW). In time, the results became quite predictable, so I can now prepare a Porsche head with confidence without spending time on the flow bench. Sometimes folks ask for flow numbers, but rarely anymore. BTW, the (almost) foolproof way to increase flow is to install a larger valve. A 2.7 intake port will flow better due primarily to the 2mm larger valves, not necessarily because it has a larger port. Best case is to take the benefit of the larger valve along with proper re-shaping of the port, which is the case on the engine in this thread.

Here's a bit more: Due to casting variations in the ports, no two 944 heads (for example) flow the same. Occasionally a head will have a good port shape bone stock, but the majority can be significantly improved.

They are 2618, which is typical for a custom JE piston. Oh no.... if there's discussion on merits of piston alloys, how 'bout a separate thread (please).

Yes, I always prefer iron sleeves since I can make the cylinder round (+/-.0002") and with proper prep they will provide a superior ring seal and more power. Further, a proper hone at rebuild time will make them good as new, and they are replaceable if needed.

 

Thanks again. I can source Mahle PowerPak 2618 3.0 turbo pistons easily here, just a little concerned about cold piston slap, hence my interest.