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Decisions, decisions. 351W vs. 408W

I’m finally ready to build an engine for my ‘67. I have a roller block 351W that will be the starting point. My plan is to get the block bored .030 over, decked, and align honed as part of the machine work. This is where my indecision comes in. While I am in there, I could go with a stroker kit, or just refurbish the stock crank and rods. I do plan on getting a new cam, new lifters, and new heads. I was thinking 190 11R or 205 11R heads and 1.6 ratio roller rockers topped off with a Pro Flow 4 EFI system. I already have a Tremec TKO 600, 9” rear with 3.89 gears, and a Magiflow 2.5” exhaust system. I would classify my intended use for the car as “spirited” daily driver. I’m not looking to turn high RPMs or race the car (unless stoplight to stoplight counts). Thoughts? Opinions?


The NorCal dude from Belgium
I asume you want to cruise also , so for a "spirited driver" I would stay with the roller 351W but with good breathing heads without going excessive.
I asume you want to cruise also , so for a "spirited driver" I would stay with the roller 351W but with good breathing heads without going excessive.
Based on this response, I’m assuming you would recommend going with the 190 R11 heads or should I consider going smaller than that?


The NorCal dude from Belgium
Don't know the specs of those heads but any good enginebuilder should know what you need. Hope this will help you out. You also could get info at enginefactory. They show some combo's on their website.

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I Don't Care. Do you?
I have TFS 11Rs on my 347. By far the very best SBF head out there. It's a lot of head for an engine for street use and the occasional red light romp. No point in using them if you're not going to run a cam with the profile to let them breathe it all in. Engines should be designed around THE WHOLE PACKAGE. That means full drive train gearing, etc. Talk to a real engine builder about it all and let them guide you if this is your first engine build. Too many make the mistake of picking this or that "hot" part or copy some other guys ride and end up with something that either doesn't perform well or doesn't meet their specific needs.
I can tell you that a bored and stroked 351W with a 205 head will work with a 2.5" exhaust but bigger would be better. I'll also tell you that heads like the 11R like to run and that means high RPMs. If shifting at 5-6k is not your thing go with a more street style head. Fun on the street is made with an engine that likes to go from 1600/1800 rpm up to maybe 5k. Low end torque over high rpm HP is what it sounds like you want.
Talk to a real engine builder about it all and let them guide you if this is your first engine build.
Everything you stated makes perfect sense. The problem I have is with the local engine builder. I’ve asked around about local engine builders and the consensus about the local shop is that they USED to be good when the old man ran things but now his kid is running the shop and things aren’t as good. This is my first engine build so I am proceeding cautiously.


I Don't Care. Do you?
Why limit yourself to someone local? There are plenty of very good builders all over the country that can put it together for you. BUT I'd stay away from the "factory" type operations. They tend to have lots of hourly paid guys bolting stuff together with little experience. You want a builder who machines and assembles his own engines. It might take a bit longer but you get what you pay for in more ways than one. Best if you find a guy who specializes in Fords as well. They know all the areas of concern and tricks to make things work best.

Engines are not really complicated machines. To build a good one is all about details. It's very easy to put together a solid reliable 351 that can crank out 300+ HP and torque for less than a kings ransom. It may not sound like a lot of power given today's supercharged factory hot rods but that kind of grunt in an old lightweight mustang is all the fun most can handle. When one starts upping the ante on a build it can get very costly and you need to expect stuff to break under use. If you're not up for all that I'd suggest keeping things on the more sedate side. Even a mild build can light up the tires and sound mean as hell out the exhaust but you also get peace of mind knowing you're not on the edge of reliability.

Don't mean to get so wordy but I've seen so many guys go down paths they shouldn't have or could not handle. Our cars are supposed to be fun and enjoyable. 99.9% of the time you'll find yourself just cruising around or hanging in some parking lot with other car guys. Build it for that purpose. Or go ALL THE WAY if you think you want more of a race car. There is no middle ground, really. Think how you will feel the first time you get your doors BLOWN OFF by some ricer kid in a boosted to the moon Subaru at some light when you thought you're built to the hilt 351 stroker would own his ass. If you don't put the extra thousands in your engine, trans, rearend, suspension, chassis...that is what will happen again and again to you.

Sorry. Mornings I tend to ramble. lol
The main reason for looking local is because it would be a lot easier to drop off the core or stop in to see how things are going. I’ll start expanding my search to see if I can find a place that has the attributes you mention.

I don’t have an HP number that I am chasing like a lot of other people seem to start off with. I want something that will be reliable while also having some fun when I have to mash the skinny pedal.

The car is set up to be more aggressive if need be: TKO 600 trans, 9” 3.89 gears with True Trac, upgraded disc brakes, coil over front suspension, and subframe connectors. The engine is the last big piece of the puzzle.


  • It seems like everyone has to go through this for themselves to believe it, but take it from a guy with an expensive 525HP 408w beast, it’s just not necessary. And stroker cranks have been getting a lot of bad press lately regarding machining tolerances. There’s a lot to be said for the bulletproof 351w OEM crank too, besides the fact that you already have it.
  • With the Pro-Flo, some nice torquey aluminum heads, a roller cam and ARP rod bolts, you’d have a 425HP engine with amazing manners and still have the ability to light the tires at will.