351 Cleveland Build

[78 Mach1]

I have a completely rebuilt 351 Cleveland long block. It was a mild build to factory specs. It dynoed at a Max Horsepower of 244.3 at 4700 RPM and Max Torque of 313.5 at 3400 RPM. It was originally a mild build to go into my truck. But plans have changed and I now want it for my Mustang. There for I need to bump up the power quite a bit. The overall plans are for it to be a weekend racer but yet maintain good enough manners to be driven on the street occasionally. Not that I have any future plans to race it, but that is the overall theme of the car build and I need the motor to back up this look.

I purchased a set of 4V closed chamber heads. They came off a running and driving motor in a Pantera. The owner upgraded to aluminum heads and sold me his factory heads. They are date code D0AE and D1AE. According to the previous owner, the heads were freshly gone through 5 years ago and have very few miles on them. This seems to be backed up by the condition of the heads. Very clean and no noticeable wear. They have the standard non adjustable rocker arm pedestals. And here is where my first questions come in. I plan to get the heads machined to accept a 7/16" stud and guide plates. The end goal is to put full roller rockers on these heads. Not that I need them, but i happen to have a set and would like the reduced friction of the roller rockers. When I search ARP rocker studs for the 351 Cleveland, many different options come up. I'm not an engine builder and need guidance on this. Are there a specific set of studs I should be looking at? Are there other factors to consider when purchasing the new studs? Do I have to get specific ones to keep my valve train angles correct? Please help me with information to ensure I get the correct studs the first time. I'm pretty sure the 7/16" ones are what I need. But from there, I'm lost.

I appreciate any help you guys can provide.

 

[78 Mach1]

I have a completely rebuilt 351 Cleveland long block. It was a mild build to factory specs. It dynoed at a Max Horsepower of 244.3 at 4700 RPM and Max Torque of 313.5 at 3400 RPM. It was originally a mild build to go into my truck. But plans have changed and I now want it for my Mustang. There for I need to bump up the power quite a bit. The overall plans are for it to be a weekend racer but yet maintain good enough manners to be driven on the street occasionally. Not that I have any future plans to race it, but that is the overall theme of the car build and I need the motor to back up this look.

I purchased a set of 4V closed chamber heads. They came off a running and driving motor in a Pantera. The owner upgraded to aluminum heads and sold me his factory heads. They are date code D0AE and D1AE. According to the previous owner, the heads were freshly gone through 5 years ago and have very few miles on them. This seems to be backed up by the condition of the heads. Very clean and no noticeable wear. They have the standard non adjustable rocker arm pedestals. And here is where my first questions come in. I plan to get the heads machined to accept a 7/16" stud and guide plates. The end goal is to put full roller rockers on these heads. Not that I need them, but i happen to have a set and would like the reduced friction of the roller rockers. When I search ARP rocker studs for the 351 Cleveland, many different options come up. I'm not an engine builder and need guidance on this. Are there a specific set of studs I should be looking at? Are there other factors to consider when purchasing the new studs? Do I have to get specific ones to keep my valve train angles correct? Please help me with information to ensure I get the correct studs the first time. I'm pretty sure the 7/16" ones are what I need. But from there, I'm lost.

I appreciate any help you guys can provide.

Here is the information on the heads. Date codes DOAE and D1AE. Not sure if this means they are not a matched set or if Ford did use different date code heads on the same engine back then.
Also an interesting rid bit of info. The D0AE head has a 4 in upper corner and no bubble. The D1AE head has a 4 and the bubble in the corner. But yet they are obviously both clenched heads. I’ve heard that bubble doesn’t necessarily designate open or not. But never saw in person before.

 

[78 Mach1]

Also, I have a set of supposed Harland Sharp rocker arms for a 351 Cleveland. They came with some other Cleveland parts I bought. But these have no identifying marks on them. I assume they are Cleveland rockers since all the other stuff I got were for a Cleveland. But is there anyway to confirm?

 

[basstrix]

The D0AE and D1AE are the casting or engineering numbers on the heads. They have a small difference in chamber volume, but the rest is same. The date code is a little different style and in a different location. Not all that important unless you're wanting to build a "numbers matching" restoration. The D0AE head will have a 63-66cc while the D1AE will be 64-68cc chamber. Not a big deal, or so I've been told. The studs are pretty straightforward and can be sourced by application through Summit or similar. You'll also need guide plates and your push rods will need to be hardened. Guide plates are sized to the diameter of push rods. The machine shop who modifies the heads for adjustable valvetrain will have to match the angular offsets of the rocker pads....the stud is just a straight stud. The spec for modifying them (that the shop will use) is readily available.

I believe those rockers are probably made for a big block chevy. The Ford rockers will not be flat across the top and that angled body provides proper rocker geometry. I have a set of Harland Sharp....I can probably dig up a picture for reference. BBC rockers will work, but they won't provide the optimum geometry.

With those heads, you'll want to check what type of valves are installed. Stock, non-adjustable valvetrain came with multi-groove valves/keepers. They are literally 2 pieces of metal that have been fused together and are quite prone to pulling in two.....the result is catastrophic, as you might imagine. It's recommended to replace with a set of single groove valves and the corresponding retainers.

 

[basstrix]

This is a 1.73 Harland Sharp rocker. See how the top is not flat, like yours is?

 

[Cleveland Crush]

Just fyi, Harland does/did make a flat top (non arched) 351c/429 roller rockers. This version was their original Cleveland design for many years.

 

[78 Mach1]

You'll also need guide plates and your push rods will need to be hardened.

Thanks for the detailed response. The rockers did come with pushrods. But not the guide plates. I’ll research guide plates when I look for the studs as well. I’ve also heard the pushrod length may be specific to the build. Any input on that? Or are they pretty generic for all Cleveland’s with roller rockers? I will test for hardness using a file to confirm they are hardened.

The spec for modifying them (that the shop will use) is readily available.

I believe the spec is in my Ford Performance book.

With those heads, you'll want to check what type of valves are installed.

I’ll check what valves they are tomorrow and let you know.

 

[78 Mach1]

Harland does/did make a flat top (non arched) 351c/429 roller rockers.

The Cleveland mine supposedly came out of was a much older build. So it is possible they used the early Harland Sharp 351C rockers. It’s also possible they used the Chevy ones. I’ve heard of that as well. That’s why I was hoping there was some way to positively identify which ones I have.

 

[Hemikiller]

IMO, before investing in machining the heads, I'd try to find a match to one or the other. A 3-4cc difference is not a huge deal, but when you add in the costs of the machine work, it might make sense.

It was a common thing to use Big Block Chevy rockers on 351C engines, as they were easier to get and much less expensive. The problem is the rocker geometry is incorrect.




Another option to consider is the Scorpion 3224 Endurance series rockers, which are an adjustable, bolt down style rocker.

https://scorpionracingproducts.com/...series-rocker-arms-set?variant=41263471493171
The bubble or "dot" in the corner is present on almost all 71 model year and later 4V heads. Only the very earliest of D1AE-GA heads didn't have it. Urban legend is it designated a revision to the cooling passage design.

Pushrod length will be determined once you have the engine mocked up. You'll perform a couple test sweeps with a lightweight checking spring in place to get a pattern on the valve.

 

[rcadd1ct]

Yes it is best to buy a push rod checker and reduced effort springs to measure for proper push rod length after mock up assembly assembly

Decking the block/heads and other non stick parts make it important to measure and fit the proper push rods. If you don’t you won’t have to rocker properly over the valve tip and it will wear wrong.

 

[tony-muscle]

IMO, before investing in machining the heads, I'd try to find a match to one or the other. A 3-4cc difference is not a huge deal, but when you add in the costs of the machine work, it might make sense.

It was a common thing to use BBC rockers on 351C engines, as they were easier to get and much less expensive. The problem is the rocker geometry is incorrect.

View attachment 84474


Another option to consider is the Scorpion 3224 Endurance series rockers, which are an adjustable, bolt down style rocker.

https://scorpionracingproducts.com/...series-rocker-arms-set?variant=41263471493171
The bubble or "dot" in the corner is present on almost all 71 model year and later 4V heads. Only the very earliest of D1AE-GA heads didn't have it. Urban legend is it designated a revision to the cooling passage design.

Pushrod length will be determined once you have the engine mocked up. You'll perform a couple test sweeps with a lightweight checking spring in place to get a pattern on the valve.

This is very interesting. I am reading more about it and I wonder if should take a second look at my set of Scorpions. I currently have the Scorpion 1023s which are indicated for BBF. I see that the 3224s are also indicated for BBF and 351C. I have also heard that the only true Cleveland rockers would be the Yella Terra. That said, do the 3224 have the true Cleveland geometry? What are the consequences of using BBF instead of Cleveland. The YTs are twice as expensive. Are the Harland Sharp true Cleveland geometry? It is confusing because they are all indicated for BBF and 351C.

 

[Hemikiller]

This is very interesting. I am reading more about it and I wonder if should take a second look at my set of Scorpions. I currently have the Scorpion 1023s which are indicated for BBF. I see that the 3224s are also indicated for BBF and 351C. I have also heard that the only true Cleveland rockers would be the Yella Terra. That said, do the 3224 have the true Cleveland geometry? What are the consequences of using BBF instead of Cleveland. The YTs are twice as expensive. Are the Harland Sharp true Cleveland geometry? It is confusing because they are all indicated for BBF and 351C.

The BBF (429/460) use the same rockers as the 351C/351M/400. The problem is people, myself included, were using Big Block Chevy rockers.

 

[basstrix]

Just fyi, Harland does/did make a flat top (non arched) 351c/429 roller rockers. This version was their original Cleveland design for many years.

Those are 1.6:1 Ratio rockers for Small Block Ford applications running a 3/8" stud. Not recommended for a 351 Cleveland.



The picture below is a comparison of a 1.7 Big Block Chevy (top) vs a 1.73 335/385 Series Ford.

 

[basstrix]

@Hemikiller great input, as usual. Didn't see your reply until after I made mine .

@tony-muscle I did quite a bit of research into Jim Miller's "Mid Lift" valvetrain geometry. It was in one of his articles where I read that Yella Terra was one of the few rockers that would provide "complete" mid lift geometry. There are many videos and articles out there, but most of them only address the valve stem half of Mid Lift geometry. True Mid-Lift places both moment arms (valve stem to fulcurm and fulcrum to push rod) at a right angle to their respective actuation device (valve or push rod) at 1/2 of valve lift.

That being said, I put together a kinematic model to get an idea of how much the non-perfect rocker was diminishing the ideal valve geometry of Mid-Lift. Long story short is the valve halve is much more important to get correct. In my opinion, unless the pushrod side is way off, the benefit isn't substantial to get both sides perfect at Mid Lift, but certainly get the valve side right.

Interestingly, Miller references Harland Sharp rockers as violating the Mid Lift geometry. Crane Gold and the old Ford Motorsport were some rockers he says meets Mid Lift.

 

[Cleveland Crush]

The Cleveland mine supposedly came out of was a much older build. So it is possible they used the early Harland Sharp 351C rockers. It’s also possible they used the Chevy ones. I’ve heard of that as well. That’s why I was hoping there was some way to positively identify which ones I have.

Those are 1.6:1 Ratio rockers for Small Block Ford applications running a 3/8" stud. Not recommended for a 351 Cleveland.

View attachment 84482

The picture below is a comparison of a 1.7 Big Block Chevy (top) vs a 1.73 335/385 Series Ford.

Those are 1.6:1 Ratio rockers for Small Block Ford applications running a 3/8" stud. Not recommended for a 351 Cleveland.

View attachment 84482

The picture below is a comparison of a 1.7 Big Block Chevy (top) vs a 1.73 335/385 Series Ford.

View attachment 84480

View attachment 84480

Sorry for any confusion on my generic web photo. My only point was informing the OP that Harland manufactured the non arched flat top rocker for true Cleveland/429 specific applications for many many years(exact same design in my generic photo). The profiled arch design is just a newer version.
Thanks,
Chris

 

[basstrix]

Sorry for any confusion on my generic web photo. My only point was informing the OP that Harland manufactured the non arched flat top rocker for true Cleveland/429 specific applications for many many years(exact same design in my generic photo). The profiled arch design is just a newer version.
Thanks,
Chris

Not to beat a dead horse, but can you post up the PN of the flat top? My first picture is a rocker I bought in 1989.

 

[tony-muscle]

The BBF (429/460) use the same rockers as the 351C/351M/400. The problem is people, myself included, were using Big Block Chevy rockers.

Yikes, I misread as BBF but it was BBC. Thank you for the clarification.

 

[Cleveland Crush]

Harland #4005. I ran many sets on various Cleveland's over the years. They had enough confidence in their product they had a lifetime warranty!!!
But to the original poster 78 Mach1, I question if your rockers are Harland-Sharp, they appear too Red vs Harland's Orange anodizing.
Take care.
Chris

 

[basstrix]

Harland #4005. I ran many sets on various Cleveland's over the years. They had enough confidence in their product they had a lifetime warranty!!!
But to the original poster 78 Mach1, I question if your rockers are Harland-Sharp, they appear too Red vs Harland's Orange anodizing.
Take care.
Chris

That's a nice stockpile of rockers you got there. Thanks for the PN.

 

[78 Mach1]

It's recommended to replace with a set of single groove valves and the corresponding retainers.

Here are the valves I pulled out. I’m guessing these are the multi groove ones you are referring to.



Guess this means I need to replace the valves? Just for my knowledge, is this a requirement, or nice insurance? Reason I’m asking, is I know there are many things that are nice to do but not necessarily required. I don’t mind spending money where I need to, but also don’t have the budget to spend unnecessarily. But I certainly am willing and wanting to do it right if it prevents catastrophic failure later. Which would obviously be much more expensive in the long run.