vortec 062 heads....?

[superninja427]

Ok I've got a set of 062 vortec heads and since I'm putting a carb on my truck, I'm wondering what the cam size limit is on these vortec heads. They're factory by the way. I'm taking them to a machine shop to get them cleaned up a little basically but they have stock springs and everything. So what I'm wanting to know is what is the most lift that these heads can handle?

 

[MIHELA]

Sames as all the other factory Vortecs. It's .450 IIRC.

 

[beast94]

A safe limit is between .450 and .470. Ultimately you need to measure you clearances to ensure you have .050 (minimum) between the bottom of the retainers and the top of the valve seal. You can purchase a valve guide cutter and arbor for about $60 which will allow you to increase your retainer to seal clearance. Another thing you need to be worried about is your valve spring clearance. You want a minimum of .050 also on your springs to ensure that your coils are not binding. Now you can do some math with this # to help select springs if you need some new ones. You take 1.7 inches (valve spring installed height) and subtract your total valve lift (if your running a higher than rocker ratio than 1.5:1, then you will have to find your new total valve lift). Once you have this # you can then subtract your coil bind height of your springs to find out your theoretical coil clearance. You will still have to measure though, but this will help you select springs initially. Don't forget to match your springs to your cam (the cam manufacturer will have a suggested spring. If the suggested spring's spring height and/or spring diameter do not match the stock 1.7" (installed height) and/or 1.25" (spring diameter) sizes then you can either find 1.7" tall and 1.25" diameter springs that are a close match on the open/closed spring pressures (about 5-10 pound difference) or you can machine your stock heads to accept the larger springs. The important #'s to match are the spring's open/closed poundage's.

 

[slowburb]

Your best bet, instead of all this grinding and clearancing, and machining, and buying parts, and measuring....

Look at .450" lift limit oval track cams. Choose your duration and LSA based on where you want the peak.

 

[superninja427]

If you don't mind me asking, why oval track cams? What's different?

 

[woody80z28]

The stock LT1 grind is about perfect for Vortecs, but you'd have to convert to roller.

 

[slowburb]

Certain classes of roundy round racing have limitations on parts that keep them at certain "stock" specs...or certain maximum specs, like say a maximum .450" lift rule class. Those are the cams I'd be looking at. Easy on the valvetrain, good for longevity, and with the duration of your choosing, and LSA of your choosing.

 

[superninja427]

If you don't mind me asking, why oval track cams? Like what's different from a regular street/strip cam?

 

[superninja427]

Sorry phones messing up. But alright. Really appreciate the help!

 

[FastOrange]

im running .490 lift with just a springs change.