Re: push rods
347, it depends on how much bigger.
You will definetely need to revise the geometry of your valve train
to get it to work right.
I wanted to change cams in my clevo, go from the second largest solid to the largest solid cam in the crow range.
If I had chosen to go ahead, I had to have the posts of the roller rockers machined to get the geometry right, because the spring pressure was not right on the nose.
So I needed new springs, pushrods, machine the posts, and put in the cam and lifters, was going to cost around the $1500 figure to do.
There are alot of changes needed sometimes, you need a professional to have a look at it.