Hey,
I am gonna get str8 to the point:

I have 67cc TFS alum heads decked to 62ccs.
I am trying to find out how much was taken off, .03 maybe?
--What length pushrods? (ie stock or custom, ie: +.03 from above)
--What thickness gasket should I use?

Thanks
--Dan

 

TFS might know right away (?). Worth checking with them in any event just to compare notes.

 

Volume removed by decking varies from one head design to another. Ask TFS, they'll be able to tell you.

Just use the regular Fel-Pro 1014 gaskets. A couple of tenths of a point aren't worth the hassle of fragile gaskets.

No one can predict for you what the right length push rod will be for any given combination. The farther your combo is from stock, the more variables there are; the cam you are using, how much the block and the heads have been decked, sometimes what rockers you have, the length of the valves, the head gaskets.... the list goes just on and on. Get an adjustable push rod and measure it yourself using your exact parts, that's the only way to get it right. Even someone with a similar combo could need different ones from what yours will need. You don't even tell us whether you're using a flat tappet or roller cam; that's .400" inch difference right there.

Push rods mostly come in even increments of .050" inch.

 

Heads decked 5ccs (gonna find out the measurement)
1.6 Roller Rockers.
Stock valve length
.510/.507 lift cam at .050
gaskets listed above
Flat tappet hydraulic.

 

http://www.competitioncams.com/catalog/278.html
http://www.competitioncams.com/catalog/279.html

http://www.competitioncams.com/catalog/277.html

 

I just wanted to know if i could do that without getting the length checkers.

BTW, I am a little new, how do I know when a pushrod is at optimal length? I am dumb at getting rocker arm geometry right. Is the idea to get the roller tip directly on the center of the valve?

--Dan

 

You want to get it where the rocker moves the least distance across the valve stem, and hopefully is as near centered as possible on the stem, although that is not as important as the other thing. Taking care of that first issue is what holds down the wear on valve guides, which comes from the valve being pushed sideways.

Trying to guess at push rod length is one of the major causes of valve train parts breakage, short parts life, and mystery oil burning from excessive guide wear (ever heard "I just got these heads last year and I've already got valve guide smoke, these heads are a POS") in DIY hot-rod motors. It's really not that hard or expensive, and can save you alot of grief and $$$ on down the road.

Use white lithium grease or gear marking compound on the valve stem to see the rocker's travel across it. Check at least one intake and one exhaust on each head; you may find you need more than one length of push rod to get it really right. If your heads are the Twisted Wedge ones, that's especially possible.

I use the "Hi-Tech" checker that includes the range from about 7.2" to 8.0", and a hardware store spring rather than a real valve spring if necessary. A flat tappet cam is probably going to need push rods in the neighborhood of 7.8".