351C heads on a 289...How to.

65fsbkhipo · Dec 10, 2003

Guys...planning on putting a fresh set of heads on a fresh rebuild of a 289. I need to know the mods required for the change. I assume the intake manifold has to be changed (for a narrower one) and push rods elongated, and pistons have to be changed so the valves don't bottom out. What else?

Also, any recommendations as what parts are best. Feel free to chime in, this is gearing up to be a Boss 302 clone engine.

Ozsum67 · Dec 10, 2003

Will the bolt holes line up?

slapper · Dec 10, 2003

I don't think the Cleaveland heads will go on a 289???

fess40 · Dec 10, 2003

Do a search on the net for "Clevor", as in a combination windsor-cleveland. Last I heard Bush Performance I think was making the intake, but someone else may have it now.

65fsbkhipo · Dec 10, 2003

Weren't the Boss 302's...a 289/302 block with 351 closed chamber heads? I think they should bolt up fine other than changing the size of the bolts themselves.

65fsbkhipo · Dec 10, 2003

DH, where are you when I need parts advice.

What about you SD?

66 BLAKE 96 · Dec 10, 2003

What's the benefeit of the swap besides the wow factor?

Seems to me, with all the great aftermarket head options that it would be way easier, and probably cheaper to buy AFR's, Edelbrocks, etc. and get just as good or better results.

muh'stang · Dec 10, 2003

65fsbkhipo said:
Guys...planning on putting a fresh set of heads on a fresh rebuild of a 289. I need to know the mods required for the change. I assume the intake manifold has to be changed (for a narrower one) and push rods elongated, and pistons have to be changed so the valves don't bottom out. What else?

Also, any recommendations as what parts are best. Feel free to chime in, this is gearing up to be a Boss 302 clone engine.

Detailed link with pics http://www.themustangshop.com/clevor.cfm

D.Hearne · Dec 10, 2003

The only Cleveland heads, I'd recommend putting on a 289 are a set of "Aussie" 2 bbl's. These have the smaller ports and valves of the US 2 bbl heads with the Quench chambers of the 4 bbl ones. You will also need a Boss 302 intake or a "clevor" intake ( these were made by a company in Ft. Smith Ar. , can't recall the name) to do the swap. Ditto for the headers.You will also need 7/16 head bolts the same length as the Cleveland 1/2 bolts. Pistons will also need to be cleveland style. You rods will need upgrading too, to handle the increased rpm capabilities. But with the selection of aftermarket heads out there now, doing this swap is really a moot point. You'll end up spending as much or more $$ than if you just went out and bought a set of aftermarket Windsor heads. Even though I'd go the aftermarket route on heads on a 289, A cleveland headed small block is more impressive than the Windsor headed motor.

brianj5600 · Dec 10, 2003

http://www.darkhorseracing.net/clevor_headmod.htm
This will tell you more. I thought of doing this in the mid 80s. It was a good idea then, but now there are too many good aftermarket heads to even consider it. 4 barrel heads would be silly. They were way oversized for a 302, a 289 would not even have enough torque in neutral. The aussie heads are the only way to do it on a 289! They are not cheap though. The north american heads have large chambers and would require mountains on top of the pistons to get good compression. If you built a 347, the 4bl heads would work ok with a boss 302 intake. You have to plug the water passage on the block surface of the head and redrill it on the intake side for proper water flow. As a 347 would be the only way I would consider it, but the cost is still more than the wow affect would be worth to me and you would still be down on power.

65fsbkhipo · Dec 10, 2003

From talking to my man at the shop...having 28 years of doing Mustangs, he states that a Boss 302 was just that...a 289/302 with C heads. Sure there are a few mods...ports, alignment pins, but otherwise a bolt on mod. Still haven't heard from anyone with specifics for push rods or anyone that has actually done this. I have learned that the pistons have to be changed because of the valves, intake changed...anything else?

D.Hearne · Dec 10, 2003

They are as he said a bolt on, well sort of. Like Brianj5600 said, you have to plug the water passge in the head that normally goes to the block on a Cleveland and open up a new passage where the Windsor needs it, Boss length pushrods will be close to the length that you'll need ( this will depend on your valve train geometry once you have done the final assembly) There are no alignment pins. There are alignment dowels, but these are the same in location as the windsors. The Aussie heads run about $350 a set, bare, and will need to be rebuilt, unless you luck out and find a set, someone else has done and needs to unload them. The intake will set you back about $450 ( again unless you find a steal) Headers will need to be for a 69-70 Boss ( these are going to be hard to find, most likely) So unless you get really good deals on all the parts, you'll need, you're gonna be looking at spending as much or more than you would by simply going the aftermarket head route to get the same performance.

Edbert · Dec 11, 2003

D.Hearne said:
So unless you get really good deals on all the parts, you'll need, you're gonna be looking at spending as much or more than you would by simply going the aftermarket head route to get the same performance.

I couldn't agree more with that statement except I'd say you'll get BETTER performance (real and potential) out of a set of AFRs than you will out of Cleveland iron heads. A nice set of aluminum heads has more "wow" factor than any clevor setup would unless you have clear valve covers (canted valves ARE cool).

Turbo II · Dec 11, 2003

Cheapo "Clevor" in progress based on Hot Rod "Bogus Boss" article.

Free 351 heads, home-made intake adaptors, Ebay valve covers:

Budget so far..~$75 and a lot of spare time.

Won't be a screamer as they are open chamber heads, aftermarket or Aussie would be MUCH better but I figure if I can build it for under $500 and it runs as well as a stock 302 what the hell

D.Hearne · Dec 11, 2003

Why did you need intake adapters? Other than the bolts being out of place, the windsor intake will sit right into place with the cleveland heads. I recall there's a guy in Sweden or somewhere in that neighborhood that adapted a 351W EFI intake to his Cleveland without port plates. I mocked up a set of 2 bbl C heads on a 302 block awhile back and a 302 efi intake set right into place with the C heads.

Turbo II · Dec 11, 2003

D.Hearne said:
Why did you need intake adapters? Other than the bolts being out of place, the windsor intake will sit right into place with the cleveland heads. I recall there's a guy in Sweden or somewhere in that neighborhood that adapted a 351W EFI intake to his Cleveland without port plates. I mocked up a set of 2 bbl C heads on a 302 block awhile back and a 302 efi intake set right into place with the C heads.

The problem is without the adapter plates the ports on the intake are too low and you can't get a seal around the top edges as there is no gasket space left. ( at least on a 289/302 block, the 351W may be dfferent )

I didn't go fancy with the spacers so they're crude but should work. If a person doesn't want to build the plates or can afford the "Street Boss" intake, plates are available here: http://www.pricemotorsport.com/Intake_Adapters/AP-09/ap-09.html

They were still far too pricy for me since this engine is really just an "experiment" if I can build it cheap and if it will run in the end

D.Hearne · Dec 11, 2003

I can see where they'd be needed with 4 bbl heads, you need trash can lids to cover those ports LOL. I also contemplated doing a "bogus boss" with a set of used 351C pistons and 2 bbl heads, but the project never got past the planning stage. If I ever run across a deal on a used Boss intake, maybe I'll throw one together too. Got the pistons, but I think I'd rather the 2 bbl Aussie heads to use for this.

Turbo II · Dec 12, 2003

D.Hearne said:
I can see where they'd be needed with 4 bbl heads, you need trash can lids to cover those ports LOL. I also contemplated doing a "bogus boss" with a set of used 351C pistons and 2 bbl heads, but the project never got past the planning stage. If I ever run across a deal on a used Boss intake, maybe I'll throw one together too. Got the pistons, but I think I'd rather the 2 bbl Aussie heads to use for this.

Me too, would love to use the Aussies, just haven't found any at any junkyards I wonder what shipping from down under would be?

If you get around to doing it, don't follow the instructions in the back of the Ford Motorsports catalogs (Ford Racing now) I followed their measurement's for drilling the water passages and they were way off. Have heard others found the same. Odd, considering this came from Ford itself

D.Hearne · Dec 12, 2003

Turbo II said:
Me too, would love to use the Aussies, just haven't found any at any junkyards I wonder what shipping from down under would be?

If you get around to doing it, don't follow the instructions in the back of the Ford Motorsports catalogs (Ford Racing now) I followed their measurement's for drilling the water passages and they were way off. Have heard others found the same. Odd, considering this came from Ford itself

You don't have to go Down Under to get em, there's lots here in the US already. Do a search for "Ford Heads" on ebaymotors.com, there's always a couple sets there everyweek. I've also seen them on other sites for sale as well.

thumper460 · Dec 14, 2003

We have done 4 engines... "Bogus Boss 302s" We are twisting the last one to 7500 rpm with stock 289 rods and boss 302 pistons ( aries), the rods were fitted with ARPs ! Stock 302 crankshaft and the stock 289/302 block!! modify the water ports in the C heads ( details all over on how!!) Boss 302 intake and solid roller camshaft!! push rod length is the same as the Boss 302, rockers are the same as the Cs ( 1.73) Get into that web on "price Motorsport" they will and are making every adapter needed for almost any 351C head engine!! We are now doing a 351W lower and 4V closed chamber and a Boss tunnel ram!! H-beams and BRC custom pistons!! Oh, and a pro-fogger!!

The use if the Aussie is a good choice for a killer street car!! the huge valves and ports make a good 7500 rpm engine and yes... the wow factor is killer!! Jack Roush made 550 HP from a 302 -4V head in the 70s!! and that was with OLD TECH!! the power is there!!

You CAN run the flat top piston BUT you will need to notch for the canted valve and keep the cam small!!
Have fun!!.....

Just me..................................

Thumper

351C heads on a 289...How to.

65fsbkhipo

Ozsum67

Too much thin air

slapper

fess40

65fsbkhipo

65fsbkhipo

66 BLAKE 96

Native Texican

muh'stang

If I were rich, I'd make sure all the scoops on my

D.Hearne

New Member

brianj5600

Active Member

65fsbkhipo

D.Hearne

New Member

Edbert

Turbo II

D.Hearne

New Member

Turbo II

D.Hearne

New Member

Turbo II

D.Hearne

New Member

thumper460

Similar threads

351C heads on a 289...How to.

Too much thin air

Native Texican

If I were rich, I'd make sure all the scoops on my

New Member

Active Member

New Member

New Member

New Member

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency