Do you guys know what will happen if I put a .512 lift cam on a 85 z28 engine with stock heads? Thanks.

 

The valve springs that come on stock heads can't handle that kind of lift. You will experince coil bind and eventualy failure. Buy some valve springs that are reccomended to your cam and install them, also check your piston to valve clearance.

 

not a good match for your heads without changing springs and screw in studs. you'll need aftermarket retainers and trash the factory set up.

------------------
ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

 

Explain to me what kind of studs and springs I need. And about how much that is going to cost me? Also, why would I need to check my P to V clearance? I'm just learning all about this kind of thing. I'm rebuilding my 305 and making it performance so I'll be posting on here a lot. THanks.

 

JM,

You'll almost certainly need longer push rods as well. You may need to machine the valve guides to allow for the extra lift, elongate the push rod guide holes to prevent push rod binding, and machine the spring seats to accomodate larger diameter valve springs. That would also be an excellent time to machine the rocker stud bosses and tap the holes for screwed studs.

As for the V/P clearance, you can calculate the valve lift and comapare it to the deck height at the moment of maximum valve lift. Once you get close to 0.050" or less, you should really use modelling clay between the valve and piston to check your calculations.

The "SEARCH" feature of the boards will undoubtedly be a very useful tool for you in your project. There is a lot of information in the archives.

------------------
Later,
Vader
------------------
If you want to beat the World, it might reach up and pull you down...
Adobe Acrobat Reader