what is the compression ratio of a un modified stock L98 350 TPI engine?
what is ideal compression ratio fro a 350 with a ported edelbrock high flow TPI with a LPE 211/219 cam.

I believe it's 9.3:1 according to the books. I'd say that or a tad higher like 9.5:1 is ideal for running all kinds of fuel. With a premium only gas or aluminum heads I'd run 10.1-10.5:1 for sure if boost is out of the picture...