Not only the lift, but make sure your duration is good for at least 7200 rpm. I also agree with the Victor Jr., even a Super Victor...
Jim

Laying down
 

I use a Bullet 255-263 @.050 with .640 lift in my 360 and in my 388 and it does very good. Jet ext won't hurt a thing but my thoughts are it would show up right after the hit if it was going dry .also I would want the cam on 106 max and degree to 102 0r100 . Later J.Smith 4621 racing

Make sure your valve springs can handlle it.

Alot of proline heads ressemble stock gm heads.

Are you sure there 220 intake runner? I know the 170cc have 220 stamped in the head, it was part of the casting number at the factory and not the intake cc's

and they were 2.02 1.6 and 72cc

I WOULD CHECK THE VALVE TO PISTON CLEARANCE WHEN YOU GET THEN NEW BIGGER CAM IN... GOOD LUCK...

I wouldn't worry about changing the intake, I've gone 10.60's with a box stock Hurricane on a 383.

You need a bigger cam. That cam is done way before 7000 rpm. Check out the Comp 12-908-9. It hauls a$$ in a engine such as yours. Specs are:

300 in/308 ex adv. duration
264 in/270 ex duration @ .050"
.630 in/.630 ex gross lift
106 lobe centers (I'd advance it 4 degrees)

to much gear or to short of a tire.

I would agree. The cam is not big enough. Also, what fuel pump and system details do you have goin on? That was never metioned. The hurricane will make more power than the Victor Jr. The cam Poyboy recomends, is perfect. That cam would work very well. To mention it again, check piston to valve, installed height, and spring pressures, and coil bind for the springs. That could be part of the issue also, not enough valve spring.

Frank