I recently discovered that I may be needing to rebuild my 350 due to the fact that may cam may have lost a lobe. I'll be checking that today. I am considering building a 383.

The heads I have on the engine currently are 2.02 041 64cc's. Am I going to need some sort of dish top piston to keep the CR and cylinder pressure pump gas friendly?

This is going to be a budget build for my DD.

Also, any cam ideas for a 5000lb Blazer 4x4? I have/had a Comp Xtreme 4x4 cam (210/218 .447/.462, 111*) that may have lost a lobe in less than 7000 miles. I loved the performance of that cam.

I would run a D dish piston, likely in the 18cc dish size, this with a close quench distance will give it excellant combustion characteristics. As for a cam I would look at comps line of 4X4 extreme cams, they`re made just for the purpose.

Exactly what he said! And you might want to read this thread on oil for cam break in. Could help you save your next camshaft. I would probably go with an Xtreme 4x4 262, the bigger engine will love it.

I have a buddy that has went through 2 Comp XTreme cams now I have (possibly, I need to get off this thing and start working on the truck) gone through one.

Also, I've been told on this board to stay away from the Comp XTreme's b/c the aggressive rams make them more prone to losing lobes.

So, I am skeptic about getting another Comp XTreme cam, even though I loved the way it performed.

I've used them successfuly in 5 engines now. I just did my research first and discovered beforehand the modern oil problem and flat tappet camshafts. I use the Comp Cams assembly lube, pour a whole bottle of GM EOS in the lifter valley, and add another bottle to the oil when I put oil in it. I use the Rotella Diesel oil courtesy of my father who owns a trucking company and still has a good supply of the older stuff and I break my cam in for a minimum of 30 minutes varying the rpms, not just cranking it to 3000rpm and leaving it there. And I keep a garden hose handy to spray the rad to keep it cool Immediately after cam break in I change the oil and filter with Rotella and add a 3rd can of EOS. Run it for 1000 miles and then use Mobile 1 Synthetic oil from then on. 1 383 in a S15 Jimmy has 32000KM on it with nary a problem. I have yet to loose a cam.

A Keith Black KB135 piston would work nice (18cc Dcup)
A comp cams DEH265H-10 #12-208-2 will run very very simular to the Comp extreme cam you had and has slightly more conservative opening/closing ramps. (more reliable)
A Crane cams #113931 Grind Number: H-266-2 (REPLACES HMV-266-2) is a good simular replacement also.
These cams were designed with more bias towards reliability than the extreme series, while still delivering the goods.
For a 383ci motor you may/or may not want to stepup 1 cam size to a
Crane Part Number: 113941 Grind Number: H-272-2 (REPLACES HMV-272-2)
Another proven great cam

Either case some moderate cylinder head porting will really wake up those good GM 041 heads. A 1.6:1 intake rocker arm is nice too.
Not all the 64cc heads are actually 64cc. Can range up to 68cc. The only way to tell is to cc yours.
I would get used to adding a bottle of GM EOS to every oil change for a long flat tappet cam life with todays reformulated oils. You could probabily split a big bottle over two oil changes after inital break in. 1/2 a $7 bottle should give the nessessary cam lobe protection while only adding minimuly to the cost of oil.