318 wont rev above 5,300

Prine said
What are your spark plugs Brand/Range...and what are they gapped to? Boost tends to BLOW the spark out under High Load situations.
I recommend nothing but NGK Copper Plugs.

If your plugs are gapped like stock specs....close them up to .028 and report back.

I agree with everyone else....you need less Final Drive Ratio to fully load that bad boy on the big end....mmm SG 3.23's

Good luck.
Click to expand...

Agreed!

Also, if your springs were done at 5300 without boost wouldn't it be worse with the added pressure on the seat of the intake valve with boost?

Maybe throw less gear, more boost, shift at 5,000 and keep the 318 alive forever. Just put 2.94's in our 318 and 2.76's in the Slant. Later