289 to 347 possible?
YZ125rider21
06-06-2006, 04:48 PM
Hey Guys I came here to get some quick info on my friends 65 mustang build up he currently has a ford 289 in it and I was wondering if we can stroke it to 347 or will we run into problems in doing it? I know you have to notch it but is that it? Tried search on here but couldnt find nothing useful...
turboEKhatch
06-06-2006, 07:09 PM
The 289 has shorter bores than the 302's which can pull the piston out of the bottom of the bore at BDC. It'll work, but it will probably wear the skirts much worse than with a 302 block. Unless you want a numbers matching car (which I assume isn't a big deal, considering a 65 coupe with a 289 isn't an exactly rare car) I would go to a junkyard and pickup a 302 block to start from there.
TheStang00
06-06-2006, 07:10 PM
The 289 has shorter stroke than the 302's which can pull the piston out of the bottom of the bore at BDC. It'll work, but it will probably wear the skirts much worse than with a 302 block. Unless you want a numbers matching car (which I assume isn't a big deal, considering a 65 coupe with a 289 isn't an exactly rare car) I would go to a junkyard and pickup a 302 block to start from there.
i think thats what you meant...
i think thats what you meant...
351wStang
06-06-2006, 08:53 PM
i think thats what you meant...
Shorter stroke yes, but the cylinders are shorter as well. As stated, with the shorter cylinder in the 289 and the increased stroke of a 347 you will be "overextending" if you will, the pistons. This will cause you problems eventually. If you are going to put the money into this motor for a stroker kit then spend about $200 and get a 302 from the junk yard. If you are local to me I will sell you a 1976 302 bare block with mains for $100. This is an older block as is supposed to be stronger than the 5.0 era blocks.
Shorter stroke yes, but the cylinders are shorter as well. As stated, with the shorter cylinder in the 289 and the increased stroke of a 347 you will be "overextending" if you will, the pistons. This will cause you problems eventually. If you are going to put the money into this motor for a stroker kit then spend about $200 and get a 302 from the junk yard. If you are local to me I will sell you a 1976 302 bare block with mains for $100. This is an older block as is supposed to be stronger than the 5.0 era blocks.
YZ125rider21
06-06-2006, 11:01 PM
I live in california, think it be way to much to ship probably...so I guess I have to get a 302 block...will all my parts switch over if i only find a bare block with no main jornals or anything?
YZ125rider21
06-06-2006, 11:27 PM
also can I use any bottom end 302 and if so up until when?
351wStang
06-07-2006, 04:05 PM
The average 302 stock bottom end is safe up to about 500hp. I cant remember the deck height on a 289 so I'm not sure if the intake will work. But I think the heads & intake will work. Dont quote me on that because I'm not positive. You would need to use a 302 rotating assembly as well. Now, again I am not 100% positive on this but I think 1965 was the year the 289 changed a little. There are 2 different 289's. The latter of them has the common windsor bellhousing bolt pattern. The earlier 289's had I beleive a more narrow bellhousing bolt pattern. If you have the earlier block then your transmission will not bolt up to a 302. Just something to look out for.
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