Looks like a cleanup job. The intake ports could be opend up and squared more, floor looks like it needs work. exhaust has not had the hump in the roof blended, or the bluges on the sides blended. The whole exhaust prt could have been blended better and squared up. Need to take the intake valve out to get a better idea of it. Looks mainly like a intake port and exhaust sand rolled. Though the port entrance to the intake looks decent He put some work into it.

Long story short, you cant go by looks period. I have seen hogged out ports flow worse than stock ports.
Get them on a flow bench, anything else will only be speculation and guessing.

The guy probably paid what he felt was a lot of money for porting on his heads a long time ago(evidenced by all the carbon build up). The heads probably had someones stage 1 porting on them and the guy just remembered all the $$ he spent on valves, resurface, stage 1 porting and years down the road thought he would get some eddys and sell the old max ported heads

Sorry, I am an optimist

That's equivalent to an economy port. If you look down the intake runner you can see the guide is narrowed a bit. The rough edges have been smoothed and a half a-ed attempt at port matching was done.
Depending on what the numbers were specifically, if they said 270 plus, did they give a pressure drop? Cause it would have to be higher than 28 inches of water. I've done 516's before and they don't flow easily. The exhaust numbers are believable, but looking at the pictures, I'm saying not likely, again, not at 28in.
150 for testing them is not bad. Basically 2 hrs of work. Tear down, clean up and flow. Possibly reassemble depending on condition.
Good lower performance truck, quench heads.

I think I could do more with my dental handpieces than that.. Sorry to say..


Chris..

Somebody's trimmed down the guide boss and probably the bowls are done...but 270 cfm with the throat that narrow...not likely...you need at least 1.100 in the throat and it looks like it's pretty much stock in the cross section dept.

Alot can be gained by porting the bowls without touching the intake ports. I still have my doubts about the heads you have, but you still don't know until you look in the bowl area and by the pics it's too hard to tell.
Fwiw though if they would of spent that much time in the bowl areas, they would of spent the extra effort to do a halfway decent port match.

thanks guys, gonna try to get them apart and some better pics soon.

From the pics they definately have some work done on them, But not much IMO.

The biggest negative factor that I see is that the Short turn doesnt appear to be touched at all. If it hasnt and it doesnt appear to be that will limit the heads flow to a max of 250 CFM IMO

Dwayne from PHR schooled me on that. The Short turn is the key to getting the stock heads to flow over 240/250CFM. mike