PUSHROD LENGTH after head gasket change?
 

I recently rebuilt a 440, no milling was required on heads or deck, the only real change was the use of an extreme energy comp cam .477 I./ .480 E. / new lifters and a new head gasket that is 19 thousands thicker than the stock one. Do I need longer pushrods than the stock ones or will the lifters make up that small difference? Any advice would be greatly appreciated by this Newbie.
Thanks in advance!

Only way to know for sure is to install the valve train and see if there is any preload on the lifter at TDC on the compression stroke.

I think that thicker head gasket may require a slightly longer pushrod.

Do you have stock rockers? I have a set of slightly used 440source adj roller rockers complete with shims, shaft and holddowns. I also have chromoly pushrods to match the rockers.

The cool thing about these adj. rockers is that the adj. screw is on top of the pushrod. If you did need for example a longer rod by .010 the adj. nut will be able to screw in and simulate a longer pushrod.

If you are interested in my set I can post up some photos.

since you are using adjustable lifters, the lifter should make up the difference

but if you want to be safe, find an adjustable push rod to be safe, and measure it until you have the correct preload on the lifter, then order the correct size

You need to determine how much different the cam is from the one you pulled out as that will also make a difference and as mentioned above check the preload, and if it is loose you know you need to replace.

pushrod checkers are pretty cheap.

I appreciate the quick responses, I just have factory rocker arms, I don't quite understand how to check the preload. I understand having the valves closed but then what am I looking for ? Is it a " feel" type of thing, if the pushrods need to be longer would I feel the looseness on them at TDC ??
Again your responses are appreciated.
thanks

What you have to do is turn the engine so that you can find the opening and closing of the valves on the cam, this will allow you to determine the points at which to measure. I used an adjustable tool when I did mine, only issue was finding the part number associated with the length, little time consuming but all worked out in the end.

from what i remember is you assemble the engine
heads on with their gaskets
you put lifters in with and pushrods along with rocker shaft
then bolt everything down correctly
to check the preload, a 20 thousands of an inch (paper clip) should fit snuggly under the clip on the lifter

this is what I remember from almost two years ago
dont go only on what i said
i would double check with a machinest first

In order to have a good Head Gasket Set for your vehicle, you must check if the parts that you will buy is compatible with the vehicle and other parts that you have placed into. Sometimes, it would act up badly because of the parts and some circumstances that would arise. But surely, your pushrod would change if ever, if im not mistaken, for it will compensate with the new parts.