Just remember... bigger is not better in 90% of all engines. The big 4V heads were short lived for a reason, just as the BOSS 302 was short lived. The 351C-4V heads had ports and vales big enough to just about put tennis balls into, yet we make more power with better low-end torque with 351W's with 180-200cc runners that barely a D cell battery will fit into. Why? VELOCITY! It's also why the 351C4V heads were redesigned to have dual quench chambers and with slighty smaller valvesd. Even Ford knew the heads had valves that were too big! The earlier open chamber heads had no quench area which made them less effecient. The quench area causes the swirl in the cylinders which makes for a faster, more even burn. This is why Hemi heads work great at wide open throttle but aren't so great on the street or at lower RPM's.... no quench area.
Big valves and big heads mean NOTHING to a real engine builder. I've built thousands of engines in my day, mostly some sort of performance or race engine, being that that's all I build.
I don't care WHAT "Engine Masters" magazine says. I was asked to do a build with them before and turned it down. It's like reading any magazine article on an engine build, they almost always screw with the dynos to make them read the numbers they want. I don't do that. That's why engines that I build that I say make 500 HP eat-up and spit out engines other builders build that they "claim" make 600 HP. I always say its because I measure my horsepower with Clydesdales and they measure theirs with Shetland Ponies.
Just an FYI, you most certainly can (and many do) mess with the data acquisition on dynos to make them read high. Pretty much any dyno is capable of reading anything if you make a few adjustments to the D pack. Most magazine articles fake or fudge numbers, and they usually have some pretty down right humorous numbers, like doing a 500+ HP 350 Chevy with cast iron heads that gets 19 MPG. If it was that simple and easy to do, everyone would have a 500HP / 19MPG engine in theor car, and that simply isn't the case... for a reason.
Guy's like me see this stuff all of the time, and the real engine builders all talk and laugh about it. It's one of our more comical conversations as to what magazine just printed the most horse crap article.
So, my point is, 2V heads will get you better low-end, off the line power, which is where 95% of your driving and RPM range will be. Yu aren't building a race engine or looking for high RPM power numbers so why use a head that was designed for that?
302 cubic inches wasn't enough to make the BOSS 302 heads work much below 6,000 RPM. ANYONE that owned or ran one of those cars (or who currently runs in the Vintage race circuit) will tell you that. Vic Edelbrock ownes a couple of them, In fact, he owns George Follmer's old Boss 302 Trans Am car that we race in the vintage car circuit and it is low on torque pulling out of the corners even in full race trim. This is one of the reasons the BOSS 302got dropped and the 351-C4V came along. More cubes makes for more air flow and velocity through the runners. Then they had the BOSS 351 which was a half breed engine that some say never existed. I built a few of those in my day too. Theyhad a 4 bolt main block and the dual quench heads.
My point is, smaller valves, smaller runners and good velocity will make more torque, which is what moves your car from 0 -60. How many times are you going to be above 5,000 RPM, and how often will you be below that? THAT is what should dictate how you need to build your engine and what components you should choose. There are PLENTY of 351W's with small ruinner heads that WILL outright eat-up and spit out BOSS 302, and 351C4v's on a daily basis. Too big is easy to get caught up into.
By the way, Scat makes a nice little 393 cubic inch stroker kt for the 351 C. I built a 617HP 393C4V (with a 100HP shot of nitrous), for a guy's Mach 1. It's in the Ford gallery of my web site if you want to see it. He WAS looking for upper-end power and he wasn't concrned about fuel economy. If he hadn't already had the 351C4v in that car, I would have probably gone with a better, more modern set of heads like the Edelbrock aluminum heads, but I had to work with what he had. Sounds like yours IS going to be driven at lower speeds and RPMs and cruising down the freeway, so I would focus more on "torue" rather than HP, and go with the smaller 2v heads or the set of Edelbrock's.
Just remember.... if you have heads that are too big or a cam that's too big, or your engine is built for upper-end horsepower, you WILL lose a race from stop light to stop light with a car that was built for better low-end torque, and you WILL feel more "stick you in the seat" kind of power with an engine that makes better torque than it does high-end horsepower. Smaller hweads and a smaller cam makes for more low-end velocity, MUCH better throttle response and is MUCH quicker from 0 to 60. THAT is where most of your driving will be.
I hope that helped shed some light on it.
So I guess you forgot about the fact that Ford created a MODIFIED engine calling it the 351 / 400 M which used smaller runner / smaller valved heads, because they made better low-end torque and fuel economy.... Isn;t that why those came in trucks? Good low-end torque with a similar block, displacement and smaller heads? Did you forget about that one? Isn't that what this is all about in the first place?
me said:Ford dropped all high performance motors from the lineup in the USA in favor of fuel efficiency in cars and low RPM work horse motors in trucks that would run on 87 octane without pinging.
Since when is anyone on here running a Nascar engine or a pro stock style engine on the street? They discontinued them because they didn't work on the street. I was referring to STREET engines, not race stuff. I used to run a 427 SOHC engine too. We still used them into the 80's. Does that mean that engine wasa good street engine?
Dirty emissions = poor burn. Take a 351W and a 351 C. Both the same size. The only major difference is the design of the heads. The Windsor is going to produce a better burn. Ford didn't discontinue the Windsor style engines for decades, but they did discontinue the Cleveland (at least in our country anyway). There's a reason for that. THEY DIDN'T WORK ON THE STREET!
Do you always take things people say out of context
So I guess you forgot about the fact that Ford created a MODIFIED engine calling it the 351 / 400 M which used smaller runner / smaller valved heads, because they made better low-end torque and fuel economy.... Isn;t that why those came in trucks? Good low-end torque with a similar block, displacement and smaller heads? Did you forget about that one? Isn't that what this is all about in the first place?
Just remember.... if you have heads that are too big or a cam that's too big, or your engine is built for upper-end horsepower, you WILL lose a race from stop light to stop light with a car that was built for better low-end torque, and you WILL feel more "stick you in the seat" kind of power with an engine that makes better torque than it does high-end horsepower. Smaller hweads and a smaller cam makes for more low-end velocity, MUCH better throttle response and is MUCH quicker from 0 to 60. THAT is where most of your driving will be.
I hope that helped shed some light on it.
I didn't take anything out of context. YOU were the one who claimed the 4 bbl Cleveland heads were bad designs. I drove a heavy asssed 71 Torino GT with a stock 4 bbl quench headed Cleveland that was backed by an FMX and a 3.00 rear way back when and it lacked nothing on the bottom end. It did turn on better than many engines when it hit the midrange, due to the big ports and valves. Granted the bottom end was helped by the cam it was saddled with, but teh heads were not and are not failures. And the SOHC 427 is making somewhat of a comeback in the last couple years. It's only fault was the low production numbers. You obviously never drove many Clevelnads on the street, or you wouldn't be so quick to put em down. The ones you did drive likely had a big assed cam, a single plane intake and a too big carb, all of which add up to a poorly performing (on the street) 4 bbl Cleveland. The Windsor has only come into it's own in the last 10-15 years, and that's not due to it being a superior design.
Your post seemed to go through all the normal 351C myths that most of the Chivy guys like to repeat. I'm almost surprised you didn't call it a big block or mention oiling!
Since when is anyone on here running a Nascar engine or a pro stock style engine on the street? They discontinued them because they didn't work on the street. I was referring to STREET engines, not race stuff. I used to run a 427 SOHC engine too. We still used them into the 80's. Does that mean that engine wasa good street engine?
Dirty emissions = poor burn. Take a 351W and a 351 C. Both the same size. The only major difference is the design of the heads. The Windsor is going to produce a better burn. Ford didn't discontinue the Windsor style engines for decades, but they did discontinue the Cleveland (at least in our country anyway). There's a reason for that. THEY DIDN'T WORK ON THE STREET!
Do you always take things people say out of context
The M-block engine was designed when first-generation pollution controls were already in place. Most Ford V8s required bulky and unsightly external tubing to feed Thermactor air into the exhaust manifolds and exhaust gas to the EGR valve below the carburetor, but this was all built in to the M-block engine.
This all made adapting the M-block to the second generation of emissions control equipment harder. One requirement of the second-generation equipment was an oxygen(O2) sensor in the exhaust, which had to be placed before the Thermactor air was added. Since Thermactor air was injected right into the block's exhaust ports in the M-block, there was nowhere for the O2 sensor to go.
It would have been possible to alter the M-block to work, but it would have required significant effort and cost. Ford decided to simply scrap the M-block engines and replace them with updated 351 Windsor engines at the small end, and a combination of the 6.9 L Navistar International diesel and the 460 at the top end. 1982 was the last year the M-block was sold.
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