Mates 304 Compression Change

[vzv8man]

Mate wants to know whether by changing the compression in his stock 304 motor, will he need a tune done on it.

[poorstudent]

I've had a few of these golden oldies... I would shave the heads 30 thou bringing compression up to about 9.1:1 and they ran fine without a tune, anymore you might have to though. But shaving the heads is a nice cheap way of bumping the comp up... you notice the torque increase. My fav car of all time was a VL 5 Litre (which was actually 304) that did a 13.9 1/4 mile with mildly ported and shaved heads, cheap breathing mods like the die grinder to the intake manifold and obligatory extractors and twin 2.5 into 3... good engine them. So easy to work on.