which pushrods ?

[vj318]

my son is almost done with the 4.0 head conversion. he is ready to put in the pushrods but  not sure if should use the 4.2  amc rods or the 4.0 jeep rods. have explored several sites and it is split bout half and half. some have said  that you have to check the preload. I dont know how this is done, can anyone help me?

[carnuck]

Put them in and with the cam lobe at it's lowest point you should be able to spin the pushrods with your fingers (or they are too tight) Too sloppy allows them to pop out too.

[eaglefreek]

My understanding is the pushrods should match the block and that's what I did when I did my 4.0l head swap. However, you should still check your preload since there are variables like deck height, how much has been removed from the head, head gasket thickness, etc. Too much preload will wipe out cam lobes or lifters.

[mudkicker715]

I remember on my first stroker which used 94 parts and 84 parts that the lifters were a different size from each other.

On my 87 258 and renix era 4.0 stroker  i made they were the same size.