There were also minor variations of the these heads. For instance, the D was an unmachined version of the C Roush and Edelbrock cast a variety of aluminum single plane race intakes for the early high port heads. These heads are no longer in production, though pop up on the used market from time-to-time. MB 62 2. The MA3 head has the largest intake port volume cc's and exhaust port volume cc's , intake flows cfm 25 in Hg as cast, doesn't respond to rpm transitions as well as B or C, has slight bend on intake port wall to accomodate pushrods, raised floor increases port radius, straightening the turn for incoming mixture and minimizing fuel separation, optimized for and larger, drag racing, circle track, etc.
The MB has intermediate port volumes cc's intake, cc's exhaust, flows cfm 25 in Hg as cast, intake port wall filled around pushrod area to straighten it, intake floor same as A3, material added to exhaust port floor increasing radius for flow, optimized for NASCAR. The MC has the smallest port volumes cc's intake, 95 cc's exhaust , at the radius the intake port floor has been filled about 0. Head is cast with combustion face and front and rear coolant outlets to allow use on W and C blocks.
Pipe plugs are provided to seal openings as needed. On Clevelands, install pipe plug in holes on end of heads. Brodix has recently introduced a bolt-on replacement for the CB head.
Nominal combustion chamber volume for the high port heads is usually listed at 62 cc's, though Ford Motorsport sometimes lists 65 cc's. The valve angles were changed to 7. Also, the combustion chamber shape was revised for very high compression levels. The resulting head requires a custom aftermarket rockershaft system, different pistons, valves, and pushrods. The ports were also made small to allow custom porting and require extensive porting to produce the desired flow numbers.
The custom Jessel rockershafts and arms cost nearly as much as the bare heads. Also, the small Yates combustion chambers 40 cc's and are designed to operate with custom pistons that are dished with a mirror image of the combustion chamber. Some racers maintain the earlier SVO heads are still superior to the Yates at least the early versions in non-restrictor plate applications. Like the high port family, there are a variety of Yates heads see table below. The C3 and C3L will accept most Ford Motorsport Yates intake manifolds and have the same raised exhaust port location.
Notes and variations are listed below. Yates Head Notes: 1. Require aftermarket shaft mounted rocker arm system 2. Staggered valves at 7. Revised combustion chamber shape for higher compression 4. Phosporous bronze valve guides 5.
Motorcraft AG-series spark plug 6. Uses same rockershaft as C3L but requires longer pushrods. Exhaust port is same as C3L. It is often refered to as a Yates head but is actually a separate design. The intake runners are raised 0. The heads come semi-finished without valve seat bores and must be ported, though bronze guides and seats are included. Intake valves up to 2. Blue Thunder C Head This is a hybrid cylinder head with C valve locations and Yates ports, aimed at the budget racer.
Two things that drive the out-the-door cost on Yates heads are that they require etensive porting and an expensive rockershaft system. Please join us at our NEW Mustangsandmore. Please notice this is a brand new message board, and you must re-register to gain access. Mustangsandmore Forum Archive Ford Racing aftermarket heads for cleveland profile register preferences faq search next newest topic next oldest topic Author Topic: aftermarket heads for cleveland madmanmike Journeyman Posts: 18 From: brenham,Texas,washington Registered: Oct posted PM In a never ending search for horsepower and torque who makes the best aftermarket head that has the highest flow numbers with the smallest port wich would promote airspeed torque and response and is a direct bolt on using existing hardware If I were spending the bucks for canted valve aftermarket heads, I would switch to a Windsor style motor and fun a race style inline valve head Just my 2 centavos Jim Sams '69 mustang Coupe C.
Posts: From: middle of NC Registered: Oct posted AM What you would spend on aftermarket heads for a cleveland, you could spend on your 4v heads getting them ported and filling the ports, get almost as much cfm and power out of them, and have some money left over.
Posts: From: middle of NC Registered: Oct posted PM It takes a really healthy smallblock to use cfm on the intakes, and I have seen more than one guy get that much, if not a little more, out of a set of factory 4v heads. The only drawback, besides the fact they are heavy, is the exhuast wont flow with a newer set of heads.
Of course he was trying to sell me a complete inch late '70s vintage prostock motor Maybe that's why he said the heads were so good But seriously, the Yates heads that show up at the Charlotte swap meet seem to flow to cfm intake according to the sellers and flow sheets they have. You would think that since all the NASCAR shops are here in town, that Yates heads would be cheap and plentiful, but that is not the case. In fact Ebay Yates heads are cheaper than local.
People associate this chamber with the smallport, 2-barrel head; however, it is also the 4-barrel head chamber for — This chamber offers zero quench and is prone to detonation. Valve shrouding is fair, but not much consolation when you consider the overall chamber. Cleveland cylinder heads were among the first to have bolt-fulcrum, stamped-steel rocker arms, which had pedestals like this. It is a no-adjust design hydraulic lifters only ; just slowly tighten and torque to spec.
The series big-block was the first to have bolt-fulcrums in The Boss head has screw-in studs and guide plates due to the mechanical lifters; however, this is a modification you can make to any Cleveland head with a good machinist.
Bolt-fulcrum pedestals are machined down to make room for guideplates, then drilled and tapped for screw-in studs. Cleveland foundry castings have this CF logo. Casting numbers accurately identify head castings.
It is a closed-chamber Cleveland head casting with cooling passages for the Boss block and induction. Note the milled pedestals and screw-in stud holes. The MA3 head has the largest intake port volume cc's and exhaust port volume cc's , intake flows cfm 25 in Hg as cast, doesn't respond to rpm transitions as well as B or C, has slight bend on intake port wall to accomodate pushrods, raised floor increases port radius, straightening the turn for incoming mixture and minimizing fuel separation, optimized for and larger, drag racing, circle track, etc.
The MB has intermediate port volumes cc's intake, cc's exhaust, flows cfm 25 in Hg as cast, intake port wall filled around pushrod area to straighten it, intake floor same as A3, material added to exhaust port floor increasing radius for flow, optimized for NASCAR. The MC has the smallest port volumes cc's intake, 95 cc's exhaust , at the radius the intake port floor has been filled about 0. Head is cast with combustion face and front and rear coolant outlets to allow use on W and C blocks.
Pipe plugs are provided to seal openings as needed. On Clevelands, install pipe plug in holes on end of heads. Brodix has recently introduced a bolt-on replacement for the CB head. Nominal combustion chamber volume for the high port heads is usually listed at 62 cc's, though Ford Motorsport sometimes lists 65 cc's.
Special versions of these heads were made for certain race teams. I have a set of narrow intake port A3's, for instance. High port heads require one inch longer head bolts or studs. If using head bolts, also use hardened washers.
A3's, B's, and early versions of the C heads had one short bolt. Later CB's got common length bolts. High port heads were designed to fit both Cleveland and Windsor block and come with combustion face and front and rear coolant outlets which get plugged with aluminum pipe plugs as needed. Where the plugs go is a function of the block, whether or not the intake has a coolant cross- over, and whether or not you run a remote coolant cross-over. For instance, if you put high port heads on a Windsor style block with a coolant cross-over manifold, the plugs go in the ends and the combustion face and a 0.
The supplied instructions illustrate the options. Use a thread sealer and make sure the plug is below or level with the deck surface. On Cleveland blocks, pipe plugs go in the holes on the ends of the heads coolant goes from block to head, intake is dry. Also an external not in manifold coolant crossover can be used to take water out the front of the heads.
Does not have the round water transfer hole required for a Cleveland block, otherwise same as A For 4. Solid metallic core with wire encased combustion seal for competition application.
Surfaces are coated with Teflon. Do not use sealer. Can be used with iron Cleveland heads. Has the one round water transfer hole required for a Cleveland block, otherwise same as A MB Same as B but for blocks bored to up to 4. Bore flange valve pockets have been added to unshroud intake and exhaust valves. Unique right and left hand gaskets.
Note: Both B and B can be used on Cleveland blocks if modified per supplied instructions. Victor Reinz and Cometic also make high port compatible headgaskets. I prefer cork. Can be peened to size. The tag on the Fel-Pro part number gaskets state they are for A3 heads but this is incorrct as the port dimensions are listed and measured as 1. Also, comes with a tube of black RTV but no end seals. There is a separate part number for wide port A3's 1. Note that many CB's are ported to a larger gasket size, so the Fel-Pro catalog lists port dimensions.
The Ford Motorsport MA gaskets have the correct wide port opening for A3 heads but I think they are no longer available. Fel-Pro makes part number , a thick three layer cork-metal-cork valve cover gasket which improves clearance if you have issues with roller rockers to valve cover clearance.
O osofast Member. I have been tinkering aorund with the thought of going with a non-ferrous head setup. My wife will kill me if she finds out??? LOL But to the point. What a great thread George, Dan Jones,Tod B, where in the world can you go and have this type of knowledge in one place and for free!!! Membership Required We're sorry.
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