From what I've read hardened seats aren't really required to run on today's gas. Thats what I've gathered from reading about porting. Seems like hardened seats are just a pain for the machinist that has to install them and head rebuilders have seen no damage incurred by using non-hardened seats. At least thats what I've read.
Hardend seats prevent valve and seat erosion. They have been standard equipment on heads since the mid '70s. They are a major pain to install, but if you are going to put alot of miles on the engine, you need 'em or your valves will slowly get eaten away.
I bought a set of gt40p heads and had them re-worked by a good shop and just let them go yesterday... Too many stories about them being tight, burning wires etc. I never had the luxury to see or run them. I do know they are heavier than sh.. and would have added a lot of weight. I really am not ready to build this car, so the motor can wait. I think I will go afermarket. E7's were on the motor before I pulled them off. There is also a guy names thumper in Florida that does porting on E7's and he claims his ported heads are better than a lot of aftermarket ones.
Thumpers heads ARE nice pieces. I've seen his stuff. I don't recall though what he sells em for. Ford's heads since the early 70's have had induction hardened seats, the seats are the casting itself. The seat area is heated electrically then quenched to leave a hardened seat that's a few thousandths deep. Depending on the machinist, the first valve job can wipe out the hardened part. Mine were refaced with a Serdi Machinea and after a year's running time there was no valve recession, so I take it the hardened area was unaffected by the valve job. If you have to have new seats installed, then you may as well buy new aluminum heads, you have that in cost if you need seats, valves, guides, guide plates,etc on old heads.
Anyone who looked at the molds coming out of the 429CJ heads on Fordmuscle.com last month, vs. the molds that came out of the Performer RPM heads, realize that there is much more to making a good head than pocket porting and wiping out thermactor bumps. Factory 429 are supposed to be good heads, and Performer RPMs not that great, and the difference is huge. IF you are a do-it-yourselfer-IF you have the tools-IF you have the time-IF you have the knowledge, you can make E7 heads perform better. Of course, you can say that about just about any head. If taking a very marginal head and making it less marginal is your joy, knock yourself out. Rather than beat people while using E7s, I would rather destroy people using AFRs. Most people are impatient. If they would just wait a little while longer, and save a little more money, they could invest in decent quality heads that they will be happy with for years. I am amazed how many people waste $700 or whatever on marginal heads only to finally buy nice heads a year later. Just save the money and buy the decent heads the first time. If you want to go fast, it will be cheaper in the log run.
Thumper charges approx. $700 and his heads perform as good if not better than most aliminum heads. If I were to run the E7's I would send out to have him work on them. It's all about what you want as well. Some may want a stock looking appearance that's why they may want to run E7's. In combination with the heads though is proper cam selection. They both work together. One cannot be chosen without consideration of the other.
While aluminum heads may be the right choice for others they aren't for me...unless their cheap. I wont be drag racing, I wont be street racing, I wont be trying to make 450 hp. I'm trying to make a decent running car. Mild porting is all I'm after. Given the design of the 69w heads I'd say a mild port is a no brainer and worth a couple days of my time. I'd rather spend the money on a better paint job.
Good points. A lot of this has to do with what your purpose is also. I always take the approach like "slightly more than stock" when building a car. Now this can be slightly extreme, or just slightly... if this makes sense. But it all ties back to the intended use of the car.
Well, if you are looking for the best Ford casting to port, the early W heads are it. Any of them, no matter how good or crappy out of the box, will respond well to porting. It's just that the W heads are the max option after all the work is done since they start out with the 'most-est' goodies. I don't know if you planned on screw in studs, but you really should, even on the street. Press in studs are notorious for pulling up. If you don't want roller rockers, grab a set of SBC 1.6 long slots.
Yes, this is the man I was referring to. If I ever decide to pull my E7's off the shelf, this is where they are going.
