Thread: biggest lift cam i should run for now.

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got a 355 small block with 305 heads on it, 58cc chambers, 1.84 intake 1.4 exhaust, runners are ported nicely and they actually flow pretty good. i have flat top pistons, .038 head gasket, and block has never been decked. how much of a cam can i go with before i start worrying about clearance issues with the pistons and valves? also, how far can i go with stock springs?

:edit: the flat tops have valve reliefs just incase that makes a difference.

set the engine at about 10*btdc and check for how much valve travel you have at that point and then plot it out till about 10*atdc---for a bit the clearance will be getting smaller and then it will get larger---then apply that info to the cam you now have and you will have an idea----of course cam timing to the crank, lobe overlap, rate of open/closing, etc, etc all will effect it---but with the right rates you could probably go to .650 with your springs/valves/retainers

well like i said, running stock springs and rocker arms for now. ive heard not to go about .475 lift on stock springs. thinking about going hydraulic rollers with my next cam. maybe even just getting new valve springs and refreshing the whole valve train. but idk. just a couple of thoughts running through my head and just needed to know what i could run.

you really need some bigger valves/ ports before you worry about the cam
For something like your deal, the vortec stuff works really well

With stock springs and rockers,I would not exceed .450" you could run into misalignment problems,you could run the Z-28 springs with long slot rockers and get up to .500" safely,if you shop around you can get both of these new for under $100.

well i found a set on summit, roller tip rockers and new valve springs from the z28 on there too, whole set 150 new. i was wanting to upgrade the whole valve train, but wanted to know for now what kinda cam i could run. i plan on getting the heads redone with the bigger valves. but the heads i have are the HO heads for the 305, they flow really good believe it or not, just too small of an intake valve. i got another set of heads that came on the engine when i got it, basic bland heads, but they are 76 CC which is none benificial to me. i like my 58cc chambers and my 11.5:1 cr lol.

also, as a side note, the came thats in there is stock for the 350. i have an Isky 256 Super Cam aswell, 425 lift on exhaust and intake, 256 adv duration with 212 at .050 lift. 112 LSA, is this a pretty ok cam for a mild application?

so after inspecting the cam that was on there, i thought my timing troubles were making the engine run rough, but the cam i had was actually an aftermarket cam. dont know what the specs are atm, but it is rather lopey and idles rough, but sounds mean as hell so im keeping it. from the looks of it and rough measurement, it isnt over .500 lift, used a tape measurer to deduct this bit of info, but its definitly more than the standard 350 cam. id say its close to 470-485 lift on both exhaust and intake, with small LSA. just guessing here though