Higher compression, better? Why?

[Zrush]

Do you wanna hear the scary part I'm gonna be running ~11:1 compression on the new motor I'm building. However this shouldn't be a problem on the 98 octane we can get here in Australia

Hey Gavin that's what my husband's 77 280Z is currently running. Not very tame for the streets IMO but it's not my car. Compression test on the cylinders were 215+ on each. Less than 10 miles per gallon. Loud and unruly. Scares the gas right out of my poor little stock 72 240Z

Vicky

[Ed]

I'll definately have to check the cc's on my head.

Felpro offers a .020 shim that you can use with their head gasket.

I'm also planning on running a mild cam. Not stock. Would this mean that I could run higher compression with a bigger cam?

[e_racer1999]

yes... slightly. just as long as you have good duration (overlap)

[ecp48]

Ed

According to the L6 engine builder, you would have 9.82:1 without the .040 shaved off the head. You are probably looking at somewhere in the area of 10.5:1 (quick estimation based on the increase in shaving a P90 .080 on a flat top piston block. (Increase from 8.52:1 to appx. 9.82/10:1)

[Gav240z]

Vicky I'm not that fussed over it being tame for the streets the way I see it the Z was never a great car for traffic even when it was brand new. I'm sure your Nissan restored Z still has it's quirks in traffic . Therefore I may as well make it a race car that can be driven on the street ehehe