How much should a basic 340 rebuild cost?

Here are some numbers from a local shop (I'm in CA)

Block Prep Special:
Hot tank, magnuflux, bore, hone, deck and jet wash - $400
(includes labor to install cam bearings and freeze plugs )

Total Static Balance all parts, document all specs - $200
Valve Jobs from $140
Head Surfacing from $40 (Each)


As far as the heads go, if you're looking for 350-400 hp, you don't need to go to aluminum heads. The stock X heads will let you do that no problem, especially with a better valve job. You'll save money over the aluminum heads, plus on things like the upgraded head gaskets and head bolts that go with them . Also note, that for an early 340 (high compression) your pistons are over the deck, and you'll need to get the 340 specific edelbrock heads (601719). These are open, not closed chamber heads like the regular RPM's, so you lose some of the benefits of the head vs. stockers.

I have a little over $5k into my 340 rebuild. It's .060 over, so pistons were pricey. I bought a set of 308's and had them ported, they flow 264 cfm, I have $1,500 into the heads by themselves. That was before the RHS X heads came out, although, those are also closed chamber heads. The pistons on my 340 are .018" over the deck, which is the spec on the early 340's, and it makes closed chamber heads a little interesting for valve to piston clearance. That limits the aftermarket head market quite a bit. I also have some upgrades, high flow oil pump, high flow water pump, high flow fuel pump, Kevko oil pan, Harland Sharp roller rockers, ARP bolts, Edelbrock air gap intake, Street Avenger 770, etc in that price (not all are brand new). I'm hoping for close to 450 hp though, and the price tag goes up fast once you get beyond a "stock" rebuild.

Good luck with the build, I love the 340's!