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Discussion Starter · #1 · (Edited)
Hey guys, I have a 4v 351 Cleveland and I am wanting to do a Boss 351 Engine replica.

Im building a resto mod fastback and Im choosing different things I like about all the different years and movie cars. Im going 67 shelby GT500 look with all the shelby exterior and the Hertz gold stripes just on the rocker for now. Elanore/cobra wheels ( got them with the car when purchased) Eleanore shift knob, with Nitrous switch and NOS powershot nitrous kit. Boss 429 high back seats. A cool factor is that the car is a 68 that was originally highland green like Bullitt. The steering wheel is the gt500 so maybe I will have it leather wrapped like Bullit to pull some of that in.

The car came with a 1970 4v 351 C in it. I was going to pull it and replace but after some research I foundout about the 71 Boss 351. Richard Holdners shootouts have it as the king of all factory small blocks from that era, Beating out every other manufacturers small block on his dyno tests.

So, Ive decided to build a replica of a Boss 351 engine both visually and as close as possible on specs. Im trying to find the cosmetic parts that separate it from other years.

Some questions:

can it get the entire ram air aor cleaner assembly under the 67 shelby hood?

What color is the correct color blue?! I have both npd blues but they seem generic looking. VHT blue is too bright.

is anyone making the 351intake engine tag?

Will having ceramic coated headers take away from the “stock replica” look?


Any and all input is appreciated! Thanks guys!
808982
 

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Rand, I'm not understanding what air cleaner you want to run. There is a thread on our boards somewhere about a fellow with the same hood as you have who cut and raised to scoops to grab more air and look more aggressive. What about the B351 do like, specifically ? The 351C4V is no slouch just the way it is. I'd get the aluminum valve covers and get a nice wide cam ( thinking Rhino charging George P ) and add your headers. They'll look fine whith your plan. LSG
 

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Discussion Starter · #3 ·
Rand, I'm not understanding what air cleaner you want to run. There is a thread on our boards somewhere about a fellow with the same hood as you have who cut and raised to scoops to grab more air and look more aggressive. What about the B351 do like, specifically ? The 351C4V is no slouch just the way it is. I'd get the aluminum valve covers and get a nice wide cam ( thinking Rhino charging George P ) and add your headers. They'll look fine whith your plan. LSG
I thought it would be neat( for Ford people in the know) to open the hood and see a Boss 351 in a “67” Shelby. The stock big blocks weigh a ton, handle poorly and are not any faster at the strip. My plan is to do a complete roller mechanical setup and make around 450 hp. Im thinking if I could get the stock boss air cleaner and rubber seal under there and modify the boss fiberglass under scoop it could work.
 

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- If your current Cleveland is in fact a 1970 4V, it will have closed chambered heads which is a good start.

- The factory Boss 351 had pop-up pistons. I wouldn't recommend going that route. Likely, you'd run into detonation issues with pump gas. You can easily run 10:1 static compression. Talk to your machinist about finding flattop pistons with the correct height for doing so. You might have to shave the heads just a bit. (Ford tended to exaggerate their compression ratios about 1 point. So, your engine likely had 9:1 from the factory.)

- You must machine the heads for screw-in, adjustable rocker studs. The factory valve train will not work with a Boss 351 cam (or any other cam with any lift). Roller rockers will fit under the factory, aluminum Boss valve covers.

- For a high-performance Cleveland such as you're planning, definitely get lifter bore bushings installed.

- Most people who run a 4V Cleveland on the street really like a hydraulic version of the factory Boss 351 cam. However, you have many options with a roller cam. I would suggest talking with Bullet Racing Cams in Mississippi. Those guys know cams and they know Clevelands.

- It's unlikely your Cleveland still has the factory, two-piece valves. Be aware those were a problem so make sure you don't have those.

- The factory rod cap nuts were also faulty. Have your machinist install ARP fasteners for the connecting rods.

- A genuine, aluminum Boss 351 intake manifold will be hard to find; and very expensive if you do find it. You can run pretty much any Cleveland 4V aluminum intake. But I'm thinking most of them have 2V ports, so pay attention there.

- Sorry, I don't know if the 1971 Mustang Ram Air system will work with your 1967 hood.

Have fun!
 

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Randall, whats the underside of your hood look like. I'm thinking you can do it. Why are you looking at full mechanical roller ? A 351C4v can give you 450 easily with a Blue Thunder intake, headers, and a carefully selected hydraulic flattappet cam. Really, its fall off a log easy. What are you going to run for fuel ? 93 or 4 unleaded premium is NOT going to do it. LSG
 

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My advice: build what makes you happy, and don't worry about what other Ford guys will think. Most won't recognize a Boss 351 unless there's a sticker on it, and even then they won't be able to tell if you have the right intake. The ones who will know without you telling them are going to be freaked out that you have a Boss 351 in a 68 that looks like a 67, and will generally piss you off because they think you are wrong.

I'm betting you'll need to build a custom ram air section under hood, but it would be a cool mod.

If I were you, I would build a badass custom 351C, and not make it look like something it's not.

100 years ago when I was starting my project, the original 289 was unusable and I had a line on a real HiPo motor. Guys on here talked me out of it. It belonged in a K code car, and I could build a much better performing 302 for the same money.

I now have a LOT more money into it than I would have with the HiPo, but it's my build that I want, and no purist will have anything to say because they will be so spazzed out by my mods they won't be able to form words.
 

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Discussion Starter · #7 ·
- If you're current Cleveland is in fact a 1970 4V, it will have closed chambered heads which is a good start.

- The factory Boss 351 had pop-up pistons. I wouldn't recommend going that route. Likely, you'd run into detonation issues with pump gas. You can easily run 10:1 static compression. Talk to your machinist about finding flattop pistons with the correct height for doing so. You might have to shave the heads just a bit. (Ford tended to exaggerate their compression ratios about 1 point. So, your engine likely had 9:1 from the factory.)

- You must machine the heads for screw-in, adjustable rocker studs. The factory valve train will not work with a Boss 351 cam (or any other cam with any lift). Roller rockers will fit under the factory, aluminum Boss valve covers.

- For a high-performance Cleveland such as you're planning, definitely get lifter bore bushings installed.

- Most people who run a 4V Cleveland on the street really like a hydraulic version of the factory Boss 351 cam. However, you have many options with a roller cam. I would suggest talking with Bullet Racing Cams in Mississippi. Those guys know cams and they know Clevelands.

- It's unlikely your Cleveland still has the factory, two-piece valves. Be aware those were a problem so make sure you don't have those.

- The factory rod cap nuts were also faulty. Have your machinist install ARP fasteners for the connecting rods.

- A genuine, aluminum Boss 351 intake manifold will be hard to find; and very expensive if you do find it. You can run pretty much any Cleveland 4V aluminum intake. But I'm thinking most of them have 2V ports, so pay attention there.

- Sorry, I don't know if the 1971 Mustang Ram Air system will work with your 1967 hood.

Have fun!
Yes 4v Cleveland, I plan to have heads machined. It is bone stock and never been apart so planning new everything but rods and crank.
I love the sound and performance of mechanical valvetrain and the Boss had that sound. Ive run many heavily modded cars on the street and usually run a mix of race gas and or Boostane. Im still young enough that I dont mind the extra wrench time it takes to run a race engine in a street car. Haha.

i need to get a 71 boss under hood scoop and see what i got.
Thanks for the effort!
 

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Discussion Starter · #8 ·
My advice: build what makes you happy, and don't worry about what other Ford guys will think. Most won't recognize a Boss 351 unless there's a sticker on it, and even then they won't be able to tell if you have the right intake. The ones who will know without you telling them are going to be freaked out that you have a Boss 351 in a 68 that looks like a 67, and will generally piss you off because they think you are wrong.

I'm betting you'll need to build a custom ram air section under hood, but it would be a cool mod.

If I were you, I would build a badass custom 351C, and not make it look like something it's not.

100 years ago when I was starting my project, the original 289 was unusable and I had a line on a real HiPo motor. Guys on here talked me out of it. It belonged in a K code car, and I could build a much better performing 302 for the same money.

I now have a LOT more money into it than I would have with the HiPo, but it's my build that I want, and no purist will have anything to say because they will be so spazzed out by my mods they won't be able to form words.
I know most dont know the motor, but its cool right? Haha. Yeah I hear that from guys I work with. I work at a high end resto shop and we build all the Ford legends and make them Factory born perfect. But at home I like to just get loose and go with whatever.
 

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Discussion Starter · #9 ·
Im just coming back to low horse power vintage stuff after having a 780 whp 2011 Shelby. I like the thought of the roller valve train and love the sound of the mechanical cams. I usually run race gas mix or boostane. Im not much of a cruiser so when i get the cars out I run them hard for a bit here and there and sit and talk about them.
What should I be concerned of with a roller valve train? I planned to run a large lift cam so i figured it would help ease some stress. Thoughts?
 

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Randall, the rollers reduce friction, but the stress comes from the lift and the valve springs. Whats 'large lift' ? I would stay under .600 if it were mine. Did Solids YEARS AGO. Decades, actually. I'm over it. LSG
 

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Discussion Starter · #11 ·
Randall, the rollers reduce friction, but the stress comes from the lift and the valve springs. Whats 'large lift' ? I would stay under .600 if it were mine. Did Solids YEARS AGO. Decades, actually. I'm over it. LSG
Ok, so what is the best place for rollers,rockers and skip the lifters? Yes under .600 for sure. I think the comp cams extreme energy is in the 585 range. I have an old Edelbrock 351 F intake and an Edelbrock 750 carb. Not sure how well the intake will do compared to an air gap or blue thunder.
 

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Randall, I used to use alot of Crane Gold roller rockers. But I have retired, so I don't know if you can even get those particular rockers anymore or not. You DO have to be careful that someone doesn't send you a repackaged set of big block Chevy rockers. The BBC rockers will fit, kinda, and will work, kinda, but the ratio is wrong, and the dimensions are not right, and your valve guides will not like it. Get US made 1.73 rockers from HarlandSharp or T & D. When looking at camshafts, forget everything on the shelf at Comp. Everything Comp makes is a pattern designed for a Chevy. Now, because the Chevy lifter is 842 and ours are 875, the lobes will be gentler on the Chevy design. This doesn't really hurt you too much because SBC rockers are 1.5 and Cleveland rockers are 1.73. But you have to keep in mind that 99 out of 100 engine builders and cam grinders have NO IDEA how to build a 351C with the big iron heads. You either have to have Comp grind you something special, or get Bullet or somebody to do it for you. DO NOT ask them for advice, they JUST DON'T KNOW. Tell them to grind EXACTLY what you ask for, EXACTLY the way Rhino George says. They know who George is ( and, no, I am not him, but I MIGHT be his long lost brother or something ). You will probably need a MUCH wider LDA than what they will recommend. Most grinders will recommend something like a 108 or 110 LDA, and George will say 116~118. George knows better than they do on this engine. Get your cam bearings from Tim Meyer and follow his instructions. What is your engine like now ? Running ? Not ? what trans and axle are you going to use ? And where do you live ? If it is available near you, E85 makes an AWESOME street fuel. 109 octane, cheaper than gegular, and right there at the pump ! What oilpan and rpm do you intend ? Some guys need the bushings. The Eddy intake will work, but you would be better off with the Scott Cook or the Blue Thunder. LSG
 

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I have a solid, flat tappet cam from Bullet in my Cleveland. I suffered a wiped lobe shortly after break-in. I'm in the camp of roller lifters having no performance advantage for a street engine, but there are other benefits.

You'll be much better off getting a custom cam rather than something off the shelf from Comp Cams. Likely, their cam profiles are designed for small block Chevrolets and that doesn't work well in a Cleveland.

It's your car, but I think you'd be perfectly happy with an engine that can run on premium pump gas. Maybe not quite as powerful, but definitely more fun for a street car.
 

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Discussion Starter · #14 ·
Randall, I used to use alot of Crane Gold roller rockers. But I have retired, so I don't know if you can even get those particular rockers anymore or not. You DO have to be careful that someone doesn't send you a repackaged set of big block Chevy rockers. The BBC rockers will fit, kinda, and will work, kinda, but the ratio is wrong, and the dimensions are not right, and your valve guides will not like it. Get US made 1.73 rockers from HarlandSharp or T & D. When looking at camshafts, forget everything on the shelf at Comp. Everything Comp makes is a pattern designed for a Chevy. Now, because the Chevy lifter is 842 and ours are 875, the lobes will be gentler on the Chevy design. This doesn't really hurt you too much because SBC rockers are 1.5 and Cleveland rockers are 1.73. But you have to keep in mind that 99 out of 100 engine builders and cam grinders have NO IDEA how to build a 351C with the big iron heads. You either have to have Comp grind you something special, or get Bullet or somebody to do it for you. DO NOT ask them for advice, they JUST DON'T KNOW. Tell them to grind EXACTLY what you ask for, EXACTLY the way Rhino George says. They know who George is ( and, no, I am not him, but I MIGHT be his long lost brother or something ). You will probably need a MUCH wider LDA than what they will recommend. Most grinders will recommend something like a 108 or 110 LDA, and George will say 116~118. George knows better than they do on this engine. Get your cam bearings from Tim Meyer and follow his instructions. What is your engine like now ? Running ? Not ? what trans and axle are you going to use ? And where do you live ? If it is available near you, E85 makes an AWESOME street fuel. 109 octane, cheaper than gegular, and right there at the pump ! What oilpan and rpm do you intend ? Some guys need the bushings. The Eddy intake will work, but you would be better off with the Scott Cook or the Blue Thunder. LSG
Thanks for the detailed info. Alot to unpack there. I dont know “what I want” in a cam to tell a grinder what I need. Someone makes one that is tried and true right? I like race gas and boostane over e85. I ran it in my 11 shelby . Im not cheap, but I would pay a few hundred extra and get an original 351 intake before buying a blue thunder as I think they are very overpriced. Anyone have a used one?!
wngine was stock high miler. Just tore it down and its going to machine shop Tuesday. 4 speed toploader RUG M. Stock 8” rear going to 4:11
 

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Discussion Starter · #15 ·
I have a solid, flat tappet cam from Bullet in my Cleveland. I suffered a wiped lobe shortly after break-in. I'm in the camp of roller lifters having no performance advantage for a street engine, but there are other benefits.

You'll be much better off getting a custom cam rather than something off the shelf from Comp Cams. Likely, their cam profiles are designed for small block Chevrolets and that doesn't work well in a Cleveland.

It's your car, but I think you'd be perfectly happy with an engine that can run on premium pump gas. Maybe not quite as powerful, but definitely more fun for a street car.
So avoid comp cams. Someone has to make a tried cam after all these years. Ive always ran race gas or boostane mix. I ran corn in my 11 at the end. It made 780 wheel horse, so I dont think a 365 hp pump gas motor would be very satisfying.
 

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Randall, I wouldn't QUITE say avoid Comp, I just wouldn't pick one of their off the shelf grinds. Comp will do custom stuff, you look at the lobes in the catalog and choose the ones you want, and tell them where you want them to be. Used to be do-able in about a month, before Covid. I have been back to work a couple of times since retiring, when the new guys were sick or on vacation. Parts availability has become a real problem. If E85 is available near you, I'd seriously consider it. You can easily make more power than race gas, about a 10% gain if you have your carb right. Don't know about any used B351 intakes, and because they are B351 specific, they'll cost you MORE than a new Blue Thunder. If you ran E85, you can save enough in just a couple of tankfuls to pay for the BT intake. Where I am race gas is 10~12$, E85 is less than 2$. That adds up quickly. Almost ALL of the shelf cams for the 351C are not good for high performance street, so no 'tried & true' on the shelf. You have to have it ground. LSG
 

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What are you hoping to achieve by running race gas? In case you're not aware, race gas allows you run very high compression. That's all. It doesn't give the engine any more power than pump gas. You can easily build a 351 Cleveland with over 400 HP that runs on pump gas.
 

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The Boss 351 D1AE-GA heads came with screw in rocker studs and push rod guide plates. The rocker stud pads on these heads are lower than on the standard (also D1AE-GA) hydraulic Cleveland heads, which have more material on the rocker pads. Because these Boss 351 heads are prone to cracking between the rocker stud pads, I highly recommend not to machine the 351C hydraulic heads for screw in rockers. Also, the stock push rod guides were prone to cracking too. If this is a street motor, I would leave as much metal intact on the heads as possible, including avoiding putting in hardened valve seats, if the heads don't need them, and if the surface is straight, do not mill. I have the Boss 351 D1AE-GA heads with the factory screw in studs and one of the screw in pads had to be Heli-coiled. Avoid this situation. Also, do not port a 4V head, they flow good enough even with stock exhaust manifolds (IMHO).
If your goal is to make a dream machine that flies through the air like the fake Eleanor, go with aftermarket heads, intake and block. You need to treat 50 year old castings with great care as they don't make them anymore.
 

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Discussion Starter · #19 ·
What are you hoping to achieve by running race gas? In case you're not aware, race gas allows you run very high compression. That's all. It doesn't give the engine any more power than pump gas. You can easily build a 351 Cleveland with over 400 HP that runs on pump gas.
 

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Discussion Starter · #20 ·
Im certainly taking everyones advice into consideration. Do you have a recipe for this 400 + hp motor? I hear the dos and donts. The boss made 383hp and 391 torque but had 11.1 compression, solid lifter, and 540 lift cam. I dont see how that could be beatin on pump gas. But im open to hear it.
 
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