The Cleveland didn't fail in Motorsports , in fact it dominated in pro stock in the 70's . The only problem with the oiling system is that it feeds too much oil to the top end , and it only causes problems at sustained rpms over 7k . The fix was always simple , builders install restrictor plugs in the oil holes in the main webbing .

I've seen a video of a Cleveland running with clear valve covers that ran std and high volume pumps and oil drained back with no accumulation. I don't think this is an issue.

Put lifter bore bushes and a restrictor kit in a cleveland and youll never have an issue.

Hold the camera STILL, I'AM GETTING DIZZY.

So ford finally made a good breathing head, and port system, then screwed up on the oil going to the crank ,bearings and rods....... typical ford baloney.

That's why phase 4 sumps had wings for added capacity.

Use a stock oil pump with a high volume spring to fix oiling issues, high volume oil pumps empty the pan too quickly, and cause issues...

The LS Chevy has a nearly identical oiling system. People used the wrong lifters causing excessive top end oil. I ran a 400 over 200,000 miles with 10PSI oil pressure idling and 35 on the highway in a 6600 lbs truck. Didnt even have to overbore it, just new pistons and rings. Same cam too with .525 lift. The drainback holes flow more oil than you can pour it in with a gallon jug. I've even ran it 3 qts low without damage. Machine work and assembly prevent all the "problems" with Cleveland oiling systems. Tim Meyer has a very effective "fix" for the block that works well if they scare you. The Boss motors and the old M/T valve covers have stubs on the top of the covers roof to concentrate oil and drip it onto the springs. These heads were run in NASCAR without all the fixes. Port the internal passages of the oul system and the pump and you'll pick up about 15 to 25 PSI of pressure and don't use a HV pump.

If you don't use a radiused inlet at the intake face your numbers will be incomparable with others tested flow and will not accurately indicate flow. A 4V head should easily make 330 on the intake with a cartridge roll bowl blend and performance valve seat. 350 @ .600" lift with a proper short side and bowl port is attainable. Overall you're doing well.

The 28" number was derived by Smokey Yunich by averaging the depression in a small block chevy running on a flow rate device and the point at which a small block chevy head experienced turbulence due to flow becoming detached from the short side radius. It was generally accepted at the time that 25" was correct but he advocated for 28" and it reflects his reputations standing that the 28" became the standard. He did not know at the time that over 50" is easily reached by the piston depression and over 100" in a race motor at overlap. Cross flow is what you're talking about and canted valve heads are better than inline and quad valve is better still. Those are the major factors influencing cam timing requirements. Better cross flow needs wider LDA and that allows smoother idle as you find in Fords factory cams and in the modern Cleveland rip off, the LS Chevy. The design flaw in Cleveland heads is not the exhaust port, it's the short turn on the intake. The thought at the time was that there was a need to increase air speed to ram air into the chamber. While this aids in low speed output, proven Richard Holdeners testing, it limits top end output due to restriction. Notice the massive port area at the manifold face and then how much it tapers down to the bowl. That is the secret of success of the Cleveland design. This applies to both 2 and 4V heads and open or closed chambers. Small chevy builders trying to build Cleveland motors like they're Chevy's is the source of all Cleveland head complaints like no low speed torque and detonation on open chamber heads. You can run high compression on open chamber heads with a correctly setup timing curve and carb tuning without race gas.

Ford had to make some compromises with these heads due to both mass production constrains and packaging issues as far as the vehicles it was installed in. However these heads are one of the best (at least for the time) production heads ever made. I’ve built 600 plus HP 10,000 rpm Clevelands using stock 4v head castings. These heads don’t need much other then major rework including port plates on the exhaust side. Unfortunately the Cleveland blocks leave a lot to be desired, and major work is needed to make one usable. There is supposedly an Australian block that’s supposed to be the cats ass however if they exist they are so rare your unlikely to ever find one. Let me tell you there is nothing more fun to drive then a AC Cobra with a 600 HP 10,000 rpm Cleveland with a close ratio 4 speed! If that doesn’t put an ear to ear smile on your face you are probably dead.

All those vacuums! Must be 100 HP in marketing BS. How to get 100 HP per cylinder on the flow bench...more vacuums!?

The only fix I can think of is a Windsor

Btw, while you are correct it takes energy to draw air in but even if the engine dosn't fire it does recover SOME of that energy because air acts as a spring when compressed i.e. it pushes down on the piston until the exhaust valve opens. Its kinda how pneumatic valve springs work in Formula One.

Oh man, this was a long-winded explanation. You should have had a torch and camera tripod prepared!

Restrictors in the right place increase pressure, a good thing. What is the Cleveland's difficultly is the crankshaft, I can't remember which journal maybe mains #3 to rod # 5? Which ever it is when the shaft spins it blocks off oil to the rod bearing which under duress causes problems. After market cranks correct this and grooved bearings help.

I had a 71 Cleveland in a 69 mustang it had a 6 quart oil pan factory. It came out of a Torino.

4v Cleveland any good books there's alot of conflicting information on this engine.

yep ! they don't drain the heads quick enough and they can pump the whole sump into the heads at constant high rpm

Hey mate I think they only do it on the bottom of Exaust side to get the gases away faster

take that he said.

Good video i just cleaned casting dags and bumps on my VN heads in the ports, Got neway cutters, what do you recommend the 45deg seat in/ex width to be on a street engine? Thanks

I would be more interested in the port velocity than the CFM #.

25 min of dribble could have been condensed to 5 or 6 min. With a workshop like looking like that it doesn't look very professional. Then there is the forgotten fact that oil is draining back through the drain backs all the time. Big sumps are a must, but port matching the oil return holes in the head, gasket and block are equally important.

Great video, save me a lot of time. After removing the left valve cover, I noticed a pool of oil at the back of the head. I was about ready to pull the head off. Thinking the oil return was plug up. Yours was the only video that address this issue that I could fine, and it help me out immensely. Thanks

So a black top with the black top pistons and the silver top conrods Wil work nice

Hi wat fly wheel is lighter? And can I make my conrods lighter at a enjineering shop and the bottem must be balanced rite?

I had a friend back in the day who had a Ranchero with a 351C 4 barrel carb and even though it was a kickass great running engine it always had oiling problems even in great shape at 56,000 miles, cams wearing out, high oil temps etc etc. no one ever figured it out in his case.

My closed chamber epoxied 4Vs flowed IN at 0600" lift 321 CFM EX 219 CFM

63 yr old die hard Ford guy and Master ASE that always ran an extra qt of oil in the pan. It's only to much when it's off but as soon as the engine starts bingo bongo.

Hi Buddy, i thought this may be interesting and it was just a little bit. I didnt watch it all sorry. i dont have 20 mins to spend on something like this. Im a bit oposed to ARP drive shafts as i beleive they are too stiff and shockload the distributor drive gear. The 5/16 OE type shaft is, for just about all appications, a prolem free oil pump drive solution. If it does fail then its not becuse it wasnt strong enough or good enough in any way, it was something else that caused its demise. You have not convinced me to use ARP shafts.

The 351C was the most handicapped engine in PS racing for a reason. Bob Glidden dominated the field with his Cleveland powered 78 Fairmont and never lost a round, race, or event. The 500 in³ rule was a result of the most badass pushrod smaller in³ engine at that time. Current NASCAR Ford heads still retain Cleveland DNA to this day.

Tip i have found over the past 45 years of spinning wrenches on cars. With all carbs. There is an low speed circuit. That supplies fuel from idle to around 1800 rpm all by itself. Limited by the idle feed restriction. Using a wide band air fuel ratio gauge look at no load on the engine 1,700 rpm. Are you at 14.7 A/F ratio. Continue up between 3,800 and 4,000 rpm how far off 14.7 are you.. At 1700 change the idle feed restrictions. Retest. At 3800 to 4000 change the primary main jets. After getting those both to 14.7 From idle. Open the primary throttle fast. If you get a backfire in the intake. Go to a larger pump discharge nozzle. Try again. Many holley performance carbs come with 0.031" idle feed restrictions that are just right for 330 cube engine. 347 to 360s need a 0.032 idle feed restriction. To tune the secondary mains must be done after the primary jetting is corrected. Do the secondary test close to wot but keeping the vacuum below the opening point of the power valve. Change the secondary main jets to get them dialed in. Then do a full WOT run to see if you need to increase the power valve restrictions.

They should have just put an oil pump in each head and used the valve covers as the sump and the bottom pump just puts it back into the heads like a dry sump system 😅

that area is a trashed out mess

why mess with these engines?They are not used by anyone in the US. Most dont even know what they are...

The big C didn't fail Bob Glidden.

Always errors?? Maybe you should have proven your theory before you published this video. Me? I’ll back Ford knew exactly what they were doing. The oiling “problem” only occurs on engines that sit at 7,000 plus rpm for long periods of time. I doubt that Ford had that as a design requirement when they designed their road car engine.

Sorry, I didn't realize you were passing on someone's material. I thought these were your ideas. I'll make a few contradictory statements in hopes that you'll search out what's right. Let's begin. Pressure is resistance to flow and they are directly related. The more pressure you have the more resistance to flow. The less pressure the less resistance to flow. So your statement ending at 3:42, "your pressure doesn't change....you just have more flow," is false. The oil clearances in the engine will determine the pressure reading you see. You stated that correctly. However, if flow is increased then pressure is decreased. Pressure being equal to resistance of flow. We'll start there.

Does any of this information transfer to the inverse such as a big block Chrysler head which has very bad flow characteristics?

For the record...Cleveland engines never failed at Motorsport...far from it...they were dominant for years.

Should have a radius entry to the port when testing.... either a radius plate or clay... not the sharp edge... 😉

nice video

Good thought experiment, thanks. I hadn’t thought about the restriction p Area but you may be onto something there. I do believe that the 4v heads were designed with high performance in mind,which is why they are a bit lacklustre at typical street trim and 351ci. They seem to work very well on 400+ inches. A couple of comments. Your CFM calculation overlooks the fact that the intake is only open on every second revolution, so the calculated CFM number is half of what you found. But on the other David Vizard teaches us that on a well built motor at peak torque the so-called 5th cycle actually brings in more air than the rest of the induction stroke. Anyway, I don’t think either f these points changes your conclusion.

I owned a 71 Boss 351. The factory forgot to install a thing called torque.

Some consideration on intake closing point is the quality of the fuel. If the cylinder goes into detonation because you have trapped too much fuel/air charge, and end up with a too high dynamic compression ratio, you cannot utilize the additional charge of a later intake closing. So the closing must be tailored to the fuel available.

Pretty good demonstration to watch. I’d like to see you do an L67 supercharged V6 head.

Hi it 's a nice video .i've got a 71 CLEVELAND with quench 4v heads with the 2.19 intake valves. do you think that the blue ls spring could do the trick replacing the stock spring with the cobra jet cam?

Why did you delete the block squirters? It's something that should be added.

Find all the info that you find is crap. The same info is in the ford performance book, tend to believe the book, sorry