Inexpensive Engine Upgrade?
 

I have a 2.4 CIS engine that I am building for my 914. I am ditching the CIS and going with carbs and going to get some "S" spec cams. I know I need at least new pistons to do this. Can anyone recommend some inexpensive pistons to use?

In a word, no.
The least expensive sets are about double the price of a good set of Cheebie slugs......them's new....however....

A diligent search will often find 2.4L 'S' pistons.....NOS or used. A NOS set of P/Cs passed thru my hands sometime back. I sold them for $1300, as I recall. I don't know if the fella ever used them.....he got to thinking 2.7L, just as I did.

Aftermarket pistons are made by JE. Shasta uses their forgings and machines them. These are not as tightly toleranced as Mahle, due to their greater expansion when hot. They tend to rattle around a bit when cold. They are also about 2/3s the weight of the Mahles (based on an 2.7L RS piston in one hand and a Shasta in the other). Bout $1K. Different compression ratios are available. I did 9.7:1 Shastas.

Mahle has recently introduced some 9.5:1 (or so) 90 mm pistons (where were they when I needed them?) .
Dunno if they make an 84mm slug of the same compression.

You're gonna want to do something with your heads to take advantage of the cams/carbs.