RSRagtop

I've decided to get a set of centerbolt LG4 heads ( since they are the same as the TPI cars ) to swap onto my LO3. My question is what should I look for when buying heads from the junkyard. I don't want to have to do a lot a machine work. Any particular problems with these heads, like a tendency to crack? How durable are the valveguides? My 305 runs great at 160 thousand miles, do the older carb engines hold up as well? I would like to get a set of these, do a mild pocket port, add new valveseals and springs and run 'em. Thanks.

five7kid

iTrader: (14)

Rather than going through all that trouble on inferior parts, get yourself a set of World Products S/R Torquer 305 heads for '87-later and do your pocket porting on them instead. They'll run you about $600 including valves (which are 1.94/1.50 vs. the factory 1.84/1.50), springs, seals, rocker studs (which are screw-in vs. the factory press-in), and shipping from Competition Products. They'll run better without pocket porting than factory heads will with, and will run even better with the bowl work. Use 350-type head gaskets if you go with these heads.

By the time you buy used factory heads, have the guides done (one weakness of any factory SBC head), put in larger intake valves, and have the valve grinding done, you'll have more in them than the Worlds would cost you. That's even more true if you have the press-in studs removed and the heads machined & tapped for screw-in studs.

Caution on the center-bolt covers, though: The enclosed information sheet instructs you to remove the perimeter-bolt bosses so center-bolt covers will fit. I found my center-bolt '87 cover inner gasket rails were about 1/8" wider than the gasket rails on the head as-cast & machined. If I had discovered that when doing the porting, I would have widened the head rails, but as it is had to rig-up the perimeter bolts to mount & seal with the bosses ground away. Just do a fit check before the heads are assembled, widen the head gasket rails if required.

RSRagtop

I intend to buy World Products heads later on, when I rebuild the engine. Right now I don't have $800 ( I've never seen Torquers for six, the usually run like $350 each before shipping ) but I do have enough to freshen up a set of LG4 heads. I need to add new springs to my old heads anyway since I'm goin' to run an LT1 cam. I'd probably add some new valveseals while I was at it. I don't want the car to be down for a while since this is my driver, so I want all of my new parts ready as soon as the engine is apart. I don't my car out of commision while I pocket-port some heads. LG4 heads are better than LO3 heads ( and a dime a dozen around here ) so swapping them while I have the top end apart sounds like a good idea to me. I'd love a set of WP heads, just can't afford them, so LG4s will have to do.

Guest

It would be difficult at best to see a crack (or two or three) on the head, since it will be coated in carbon and those cracks are often too small to be seen with your eyes. It would be better to inspect the engine and the car, and figure out why its in the junkyard, and go from there. Just FYI the local machine shop I go to had stock heads with everything done (new valves, springs, guides, seats if needed, surfaced, etc etc.) for $550. In some ways, five7 is right, going with a new head is a better idea. It kinda depends on your experience to some extent, what the junk heads you have need, and what you can do yourself. Most people would be better off with something new, but some of us have to pinch the pennies and spend about 300 bucks on a used set without everything done to them.

I'd honestly say if you are going to get different heads later, wait. The car is running ok, right? Leave it alone.

RSRagtop

Yeah the car runs OK, but I'm gettin' spanked by everything on wheels. I already doing an intake and cam swap, so everything will be out of the way, might as well do a low buck head swap to for some more power. Like I said, my current heads need a little freshening up to work with my new combo, but rather than hang new parts on pieces that have no potential ( LO3 swirl heads areas bad as they get ) I'll swap in decent heads that have some potential ( as far as 305 heads go ). If I can't find decent heads that don't need machine work, believe me, I won't do this swap. But if I can pick up 20 hp by spending $50 to $75 more than I had planned before I got this idea, it seems like a good idea to me.