Ford Repair: 351W Cyl Heads on a 302, speed density, cyl heads

Question
Brand new late model 351W heads are around 70cc and I would like to put them on my 1987 302, ARP solved the bolt difference, what about compression? What should I use? My machine shop advises use the original heads because 351W flow too good?  Does that make sense?  Any advice would be appreciated!

Answer
Jeff-

  Unless your motor is mostly stock, the 351W heads would make a decent alternative to aftermarket heads.  If your engine is close to or entirely stock, it doesn't make much sense to be buying bigger heads because it simply won't do much good.  To take advantage of better heads, you'll need a better than stock intake manifold and camshaft at least.  You didn't mention what m odel vehicle this is going into, but if it's an '87 then there's a chance it could have a speed density type injection setup.  If that's the case you'll need to upgrade to a mass airflow system before doing any modifications at all.  Speed density cars don't take well to pretty much any modifications.  As for your compression, it's going to go down.  Not by a huge amount, and I think with a properly assembled combination you'll more than make up the power lost by lowering compression.  Hope this helps.

Steve