does anyone know what are the differences between 351c stock heads vs. steel 351c quench heads?
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Would they be steel or cast?
What I think you are really asking is the difference between 'open chamber' and 'closed chamber' heads. There is plenty of information out there if you search this forum or the internet for '351C closed chamber heads'
Basically both are a cast iron head, the 'cc' has smaller combustion chamber and will increase your compresion ratio and wake up a stock engine somewhat, but it depends what your goals are.
Julian
Basically both are a cast iron head, the 'cc' has smaller combustion chamber and will increase your compresion ratio and wake up a stock engine somewhat, but it depends what your goals are.
Julian
I was wondering if it is worth it to trade out the heads i have for the oprn ones and if if will give me more horsepower?
And how much more horse would I get between the two?
And how much more horse would I get between the two?
quote:I was wondering if it is worth it to trade out the heads I have for the open ones
I think you've got it wrong.
If you trade to open heads (meaning you now have closed chamber heads), you will get a lower compression #, and a lower HP figure.
Have you removed your current heads? Can you post a photo of the combustion chambers?
Whatever you do, toss the OEM valves and get one-piece stainless steel valves. OEM pieces (welded two-piece units) are known to shed the valve tips and ruin your engine when they do.
And do look into the offerings of aluminum heads. If you are buying new iron heads, doing full machining on them with new components, you'll be spending very close to what you would on new, fully assembled aluminum heads.
Larry
I have the open chamber on my car right now and the closed chamber sitting in my garage. the closed chamber ones have already been rebuilt.
...I have done the 'Change' and MY OPINION is: Get Them (closed chambers)on There!!! If You do nothing else but change the heads You will get a Minimum of a 40 Horsepower increase. If You still have the 'Dished' pistons, You'll be at 9.5:1 Comp. Ratio. Flat Tops will have You at 10.5:1 and even more Horsepower. That is 'Static' Compression. If You change the Cam the Duration 'Overlap' will play into it. Other Mods to Consider, but Not limited to, are: Intake Manifold and carb, Headers, Roller rockers, Electronic ignition, and That doesn't even start on the Oiling System! Stay with the Huge Canted Valves!, and You'll be way over 400 HP at the Flywheel. Now Here's the 'Kicker'; When You have done all this (and a little more, there are other 'Tricks' that must be done), If You go with a ROLLER Cam (it can be a Hydraulic); You'll be 'Kissing' 600 HP at the Flywheel! Believe it or Don't!! When loosing aprox. 100 HP through the Transaxle, You'll still be laying down 500 onto the Tarmack! Most will argue against this, but I have had a Great Pleasure proving them wrong! The downside is, You will Forever be searching for the Best Premium gasoline. Although I have never had to use a Octane Booster. And of course the factor of increased smog emissions! In Califonia we register our Cats as 'Historical Vehicles' which makes them Exempt from Smog inspections, as well as much less expensive to Register! For Now anyway!! Shssss....be careful who You tell this to...
Just make sure you don't use the stock Ford valves. They have been known to break. Get some good after market SS valves.
quote:Get some good after market SS valves.
And they must be - ONE piece valves.
I imagine someone has come up with cheapo two-piece units from offshore.
Larry
Indeed, two-piece stainless steel valves have been offered for sale for a few years, 'cause "stainless" is the latest go-fast buzz-word. Of course, the definition of 'stainless' is a steel with a minimum of chrome or nickel in it; ss-302 has so little, it rusts! Some far-east metal- concoctions have even less. If the valve offered is less than about $12 each, it's very likely made in India or China of questionable materials, and if it does not specifically say "billet". it's a welded two-piece valve of no more worth than a stocker. There are no bargain speed parts! Finally, a good ss valve will require single-groove split-locks- hopefully of forged steel not the stock multi-groove stamped steel ones, and the valve itself will have only a single groove with a hardened tip.