Looking for some guidance before i get to involved. I have rebuilt CJ engine short block and a complete CU engine, can I use the pistons, barrels and heads from the complete CU engine and with the hydraulic tappets can this system be transferred to to CJ block?
I wouldn’t use hydraulic followers but if the CJ is a late case with single oil pressure relief then it’s the same (more or less) as a CU and all the parts will interchange. If it’s an early duel relief CJ I’d definitely use solid followers.
The way I understand it is you have a CJ short block that you want to fit CU barrels, pistons and heads; they’ll all fit but CU heads will be square port as Bigherb mentioned, so you’ll need the appropriate heat exchangers (or J tubes). The CJ will probably have solid followers and cam but you can’t fit hydraulic followers to a solid cam and you shouldn’t fit used followers on another cam regardless of whether it’s solid or hydraulic. Whatever followers the CJ has leave them, and don’t mix them from one cam lobe to another. You must also use the correct pushrods – alloy for solid cam and steel for hydraulic. You can use the CU hydraulic cam rockers with a solid cam but not the other way round – hydraulic cam rockers have solid spacers, solid cam rockers have springs. I hope that makes sense.
I have the later type heat exchangers so that's ok, as for the hydraulic tappets I wont know until I strip down the old CU engine, but all In all sounds like its doable. Thanks for the advice
