i was wondering, since i don't have money for machining due to buying a tranny, i want to get my 350 up and running, it has a .487/.490 lift cam in it, early 70's block and stock heads for it, can i just throw a set of .550 lift springs in it and not have issues until i have money for decent heads

 

All running issues aside, no it will not work... the springs will be fine, but the valve guides need to be shaved down to handle the extra valve lift.

A cam that big (XE274 correct?) will be an absolute dog with any stock '70s longblock... nowhere near enough compression to make it run properly, and the heads don't breathe well enough to take advantage of a cam that size anyway.

 

yes unfortunatly i know the heads suck for that kind of cam, a 9.5:1 comp. should be enough to the cam however, as far as i now, and thank you for the response on the heads, cause i wasn't sure if it had to be machined or not, now i will prob. just wait until i can afford to have them well machined or just buy a good set of heads

and i apoligize i should have given more specs, it is a 70's block, bored .060 over with stock internals except pistons which should run 9.5:1 comp. with 64. cc chambers, i will also be running a holley 750 vac. secindary carb. and i am still deciding on the stall thinking about 2500, also still flipping a coin on whether to try some juice in it

 

Manufacturers sell things like +.050" keepers and retainers if push comes to shove.