Reply to "Info needed on Yates C3 heads and manifolds..."

There seem to be a some missconceptions regarding Yates heads, and there are some big variations between what people call Yates heads.

There are very early C3 heads (I think early 90's) with canted valves which use Cleveland rockers, and a lot of people call them Yates heads because of the C3 casting.

Later Ford took out the canting and during the 90s made a series "Yates" heads with staggered rocker pads. Somewhere in the late 90s Yates heads were changed to use a continuous rocker pad, along with some other changes.

As George mentioned, these were all cast with very small ports and chambers and substantial work is required to use them. Mine have 57.7 cc chambers so I know they can go that large.

I think the big advantage of Yates heads are that you can buy a pair that have really nice port work for maybe $1,200 bare. Some of these have really high quality expensive work, but they are effectively obsolete for Nascar, so they can be found cheap. But there are "regular" and "restrictor plate" heads which have very different porting. I have about 2000 casting date restrictor plate heads with pretty small ports which still flow about 340 at .600 lift on the intake. I think that would be really hard to get with most of the aftermarket heads with ports even close (as in small) to Mine. I think this is ideal for a street motor and is because of all the development that has gone into Yates heads.

I think the turn in the ports to the valve head is really critical, and Joe head shop won't come close to what the Nascar guys achieved. The shop that cleaned up my heads was also doing an earlier pair with a lot larger ports, and mine flowed better. The used epoxy to make the ports in the other heads more like mine around the turn, and they flowed a lot better than before.

They do require shaft rocker systems. Jesel or T&D generally, which are pretty expensive new. I fell into a new set for about $200, lucky I guess, and they do turn up, because Nascar has moved on to D3 heads and teams periodically dump their spare parts cheap, which may be new parts.

You also are limited in manifolds as mentioned above, but you can always go sheet metal.