Hi guys,
As you may notice i am chewing over the various options regarding the eventual rebuild on My 351W 2v .
One option i was going to explore was installing 1.6 + 1.9 valves,
but then i was perusing ebay and noted GT40 heads were around a similar price of purchasing, installing and porting my spare DooE heads !
Are there any pitfalls in these heads,
is it a viable option ?
Remember, this engine is going to be a cruiser not a street fighter …lol 
A good set of ported D00E heads are definitely on-par with GT40’s. How much better or worse would depend on the person doing the porting! Both are a good choice for a car that’s going to be a cruiser. If you do choose to port the '70 heads, keep port sizes small and velocity up - like you said, you want a cruiser! Hogging them out will hurt more than it helps. The bigger valves will also potentially slow things down, and run contrary to what you want, but again, that depends on the person doing the work. Focus on bowls and valve seats.
Between the two, for what you want, if you have someone who you trust to do an excellent job and knows the difference between ‘street’ and ‘drag race’, I’d prefer the D00E’s. But in stock form, obviously the GT40’s are a good choice. It would come down to two factors for me: Cost, and whether your head porter knows their stuff.
If you are planning to use cast iron manifolds, honestly, I’d pick GT40P’s. They work fine with the odd plug angles, and the much faster burn of the P’s, combined with the slightly superior flow really makes a difference. They’re also much less expensive than a GT40 typically, although you would need to do something about the weak stock springs. If you’re running a flat tappet cam, even the springs might be fine.
If your total cost is going to be over $1000, I’d personally skip all of these and go with an inexpensive set of aluminum heads. The weight savings up high in the nose would help your handling as well as performance, and you’d pick up a lot of power - mild mannered street machine or not, they’re much more efficient.
How do they all compare with the Chinese Pro-Comp heads ?
http://www.mustangandfords.com/how-to/engine/mmfp-0902-pro-comp-head-test
However, I have also heard numerous complaints about Pro Comp quality, including issues with core shift and having studs pull out all the way down to the water jacket.
IMHO, Skip White NKB heads would be better than Pro Comps or Speedway, if you’re going ‘cheap’. Edelbrock heads are a very small step up pricewise, and although they are not as advanced as the aforementioned heads in terms of tech, they are still superior to any of Ford’s castings in performance, and they are of good quality.
I think iv settled on doing the replacement 1.6-1.9 valves in my Dooe heads and a tidy up in the ports as suggested.
Plus the fact of finding a well priced set of stainless valves.
Any problems anticipated in putting these chev valves in Ford heads…?
Can i get away with not machining the heads for screw in studs …
I want to try the roller tipped rockers with built in rails .
Im sooo tempted to use a pair of new Performer heads i have squirrelled away for a different job, but i need to keep focused on the objective and not go over bored on this job…lol
Im still a long way off the build.
It’s RPMs and the attendant valvespring pressures that are required to keep things under control that will pull your studs out. If this is truly a mild street build, the screw-in studs would not be so important. Going along with that same train of thought, a low-rpm “fun” motor gets very little benefit from roller rocker valvetrain, because the frictional losses come into play a lot more at high RPMs, and with stout valvesprings. I’d be surprised if the roller rockers gained even 5 hp on the big end for this engine.
The larger valves will hurt your bottom end a little, but will start to show up around 5500 RPMs or so.
Because you want a cruiser, NOT a bruiser, honestly, I’d skip the bigger valves too! The ‘bigger is better’ mentality doesn’t really hold true here.
All that said, if it’s going to the shop to be done anyway and there’s ever a chance they’ll be used on a meaner nostalgia type car, screw in studs would be the first ‘yes’ box I’d tick, because NO ONE likes it when a stud pulls out. I’d skip the valve “upgrade” no matter what, because it’s just going to hurt torque on the bottom end, and I’m guessing this is going in front of a C4 with highway gears that needs all the grunt it can get. And the roller rockers, while not super expensive, are such a mild upgrade for this particular engine, I feel they’re just unnecessary if your old sleds are in decent shape.
Good work on the porting will get you everything you’re looking for, and more, depending on who does it. Just remember: high velocity is the key to keeping the fuel and air in suspension, and it ensures good turbulence going into the chamber. Don’t hog it all out like you’re trying to make these into Pro Stock heads, keep it modest, and your car will be a mean, responsive, gas-sipping machine with plenty of roar when you pounce on the gas pedal.
Thanks for the input smilodon,
the rollers i’m using are just inexpensive roller “tipped” cast rockers.
the trans is a FMX with 3:1 diff gears so its no traffic light dragster…lol
The springs will be stock-near stock.
The only port work would be tiding up the bowel area, and a little cleaning out the exhaust ports.
I hear what you are saying about velocity, hence not going all out with “big” heads.
The machining will be done by a local engine builder whom i have known for years and builds many big dollar engines.
My concerns with the valve installation are about geometry and not binding on the bottoms?
Unfortunately, we don’t have the luxury of being able to go to a local speed shop or over night from a big box store if i discover i need something non stock.
Hence i ask lots of silly questions to be able to think ahead of what i may need when i begin the job.
Thanks again.