My son has a 83 4X4 powered by a 350 and he's thinking of swaping over to Vortec heads. (He's low on compression in one cylinder) His cam has the following specs: 204I-214E duration @.050, .420I-.443E valve lift. Do you think this cam will be way too mild for the vortec heads and matching intake (w/625 CFM Demon)? He has headers, dual 2 1/2" w/Flowmasters, 4:11 gears and 35" tires. Yes, it's a big HEAVY truck. We need maximum torque which is why I went with the cam in the first place. He plays in the mud and pulls a bass boat with it and uses it through the winter. Thanks for any advice.

I don't mean to be a downer, but do you know the reason for the low compression in the one cylinder? It could be rings too.... hate to see you spend money on new heads if you have other problems too.

I'd do a leakdown test to try to isolate why you have low comp on the bad cylinder'

That cam is a good truck cam, and IMO, the hassle of changing it to something else will not be worth the trouble. I have experience with that cam (a General Kinetics version that was 262 adv duration), and I can say that 1.6 rockers work VERY well. They seem to pick up power through the entire rev range. Switching from a stock Q-jet intake to a Performer RPM, and adding 1.6 rockers gave me 4-5 mph and .4-.5 seconds in my '70 Nova with no other changes.

That cam looks like a good selection for a torquey truck. Vortec heads are definately torque builders... and they're a perfect match for a 350 IMO. If he keeps his RPMs low then a edelbrock performer intake manifold would help out a lot too. He can use the edelbrock performer RPM is he likes to wind it some. Long tube headers will also boost torque. I would check out that cylinder too. There is definately some lost power from that.

Thanks for the quick reply. We are going to do more testing such as checking for a bad cam or mis-adjusted rockers but the poping through the carb sure sounds like a intake valve to me. And I was also thinking of the 1.6 rockers to get a little more lift. (.448I-.472E) The cam only has 30,000 miles on it.

The old Performer Cam, a dandy in his application!! But do figure there is more power there like everybody else...

pdq67

Now he's thinking about running the World S/R Torquers for $380 each but then he can use the same intake, rockers, wire looms, and valve covers. If he does go with new rockers he can step up to the 1.6 ratio and not worry about hitting valve seals. Smart kid. Hey, we have a smart mail man...

Good heads... get rid of the rough surfaces and the casting bumps on those heads and it will improve them quite a bit.