vortec head, cam swap. some Q's

[cleansquare]

Guys, I have some vortec heads, centerbolt valve covers, ordered a cyclone intake manifold to work with the heads and the q jet.

Also ordered z28 valve springs which were recommended for rhe cam. The cam is duration 278/288 and lift .421/.444. Comes with lifters. Its an rv cam

Will this combo make a good difference in performance? Mainly lower speed towing. Going thru the gears it needs more power.

I need gaskets and thats it I think. Anything else? Will my stock head bolts work on the vortec heads? What about intake bolts?

My uncle suggested I get the timing chain gears that "will allow you to arvance or retard the cam. What is he talking about? Anything else I should be aware of? Thanks yall.

Ps engine is 350 rebuilt with headers and duals no cats and a 4l80e. 4.10s