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Discussion Starter #1
Is 8.5 to 1 compression to low to build a 68 289 motor to 280 to 300 HP? What would be your choice of parts? The reason i ask is i have a set of good 351W heads that i want to use and then maybe post the build. I have read many theads about the 289 to 351 head swap and most were just buy aluminum heads. I agree with that and would love to do that but for some reason i just want to use my 351 heads. The problem with most of the head swaps were that you would have to change pistons to get the compression up due to the larger combustion chambers of the 351 head. Keith Black makes a nice set of pistons that would get me the 8.5 to 1. This is where i want to start, the right compression would be most important. Plus if i do this and it becomes a big failure then maybe nobody will ask if you can put 351 heads on a 289 anymore.
 

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Well, there's not a big question mark floating around about putting windsor heads on a 289. People have done it for years... decades even.

The big question is whether or not it's efficient. Is it a good use of money? Does it give you any more power for the swap, or are you just trading parts?
As for the low compression thing, it's not a big deal. 8:1 is actually what most of the race engines in the Mexican Road Race use due to the quality of PEMEX fuel, which I would swear is filtered through a horse.
http://www.hotrod.com/techarticles/engine/ford_289_engine_buildup/
 

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Discussion Starter #3
Well you hit the nail right on the head.( Is it a good use of money. )That is mostly why i want to use them. Already ported, screw in studs plus they were on my old motor so i know they are good useable heads. Aluminum heads are a bit pricey and rebuilding my never even done a valve job 68 289 heads just would not be worth it. So with these heads just laying around i thought budget build.
 

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It's not a budget build if you have to tear down and bore the engine for new pistons/ rings new bearings,gaskets etc.,just to use heads you have lying around.
 

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The 351 Windsor heads are not worth the effort. Your 351W heads just barely flow more air than the pathetic 289 / 302 heads. You are better off either porting the 289 / 302 heads and installing better valves if this were 1975. The combustion chamber on the 289 heads is better and compression will be adequate.

However since this is 2011, you can buy a pair of aluminum heads for about $1200 that will make perhaps 50 - 100 horsepower at 10:1 compression compared to a set of 351 iron heads at 8.5 :1 compression.

If you weant to make 300 horsepower a more effective way to do so is to start with either a 347 short block or a 351W short block. The Windsor heads are not worth poo on a 289 or 302, not worth messing with at all on the 351W short block either. I've been there and done that.

With a 351W short block and your "good" set of 351W heads you can make 300 horsepower - that's the stock rating.
 

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Or go to your local pick-a-part and grab a pair of GT-40Ps from a 97.5-2001 5.0 Explorer. 58cc chambers (so you won't lose compression), and they are the best flowing cast iron factory heads for any SBF. Oh, and they'll have hardened seats so they'll work fine on today's Unleaded gasoline!
 

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Discussion Starter #7
It's not a budget build if you have to tear down and bore the engine for new pistons/ rings new bearings,gaskets etc.,just to use heads you have lying around.
My 289 is due for rebuild. it has never been touched and on its standard bore. Well except head gaskets some 7 years ago. I ran this motor just about as far as it can go. I am probably like most people , Don't have lots of money but want to keep the car going. I just thought this would be a cheaper way of building a nice little motor.

Royce i also thought about a 351 block since i have to rebuild anyways, and agree with everything you say even the windsor heads are not worth poo. ( compared to aluminum.) But i figure they got to be a bit better then the 289 head and that motor had plenty power for what i need it for.

I even thought of getting the newer 302 roller motor and rebuilding it. There are so many choices.
 

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Agree - if you going to go the rebuilder route anyway at that point you are better off with modern heads. Why not just scrounge up a W instead? Plenty o em out there that need a rebuild as well _ I see one on CL here for $200....running and all.
 

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You will see no increase in performance with the 351W heads.
If you want to use iron OEM heads, go with some GT40P heads as previously mentioned. A set of 1.7 rockers and a street performance valve job.
 
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