max lift

[Duntz00]

Ive got a 305 in my truck and im wanting to change the intake and put a cam in it. So my question is what is the max lift for the stock valve springs on the 305, the cam I am wanting to put in has a gross valve lift of .458, and yes I know its just a 305 and I know the old sang " You can't polish a turd" but I figure if I got the intake off might as well put a cam in it.

 

[Stomis]

What heads? .468 isnt that much lift.

 

[Duntz00]

don't have a clue what heads it has on it, its just a junky stock 305 that has to get me through the woods

 

[Stomis]

.468 is not that hot of a cam, it should be fine. If your worried just dont rev it past 4800. No reason to anyway.

 

[trailblazr81]

Whats the duration? With stock head 305 I wouldnt go over 210-212 degrees duration. And I think the lift should be fine.

 

[Duntz00]

218 is the duration @ .50
.305 lobe lift
110 lobe seperation
268 seat duration
.458 gross valve lift

 

[trailblazr81]

I dunno if I'd go 218 duration on stock non ported heads. Also I looked at Comp Cams and every cam, even smog legal with .450 and up lift state cannot use stock springs. So to be safe might want to get new springs or go with a little smaller.

 

[Duntz00]

ive all ready got the cam, its a custom ground cam I bought for my 88 chevy I had but never used. Well, if I have to change the springs im not going to swap cams cause I don't have the money and if im going that far I might as well pull the heads too and have them reworked, and im not going to put that kinda money in a junky ol' 305 so im just going to switch intakes.

 

[trailblazr81]

Well I just did some more looking and found another place where it was recommended to use a cam with .465" lift or less. So your call. Go for it and tell us what happens.