found a 302 for sale near by and called the guy up he gave them this info. has it in his fox body mustang it turns over and gets spark but cant get it to start with out backfiring and hasnt messed with the timing all that much to see if thats what is it. he traded it from another guy. he game the the number for the other guy and havent talked to him yet just a message and got this info it was orginial his fathers motor who had it rebuilt by a master ford tech in florida. had it replaced by trw parts. and bored and stroked to 351 specs. and all 351 top end. run only a couple hours but never driven then he traded the motor. the part that questions me is the 302 bored and stroked to a 351??? idk if he means a 347 but thinks that the 351 top end parts is making it a 351? is it possible? hes asking 500 bucks for it should i go look at it its still in the guys mustang and try to get it to run and get a compression test if possible?. thanks for the help before hand guys
Sounds like timing or hung/bent valves. I would want the rocker covers off for a look see before entertaining the thought of purchasing it. If he put 351 parts in it as opposed to on it, it could have some issues. Yes a compression test is definitely in order.
With a 3.4" stroke, a 302 would need to be punched out to 4.050" to become 351ci. Thats .050 over stock, past the 'safe' limit. Unless it has a longer stroke than the normal 3.4" stroker crank... it seems like a bad idea.
I guess you've never heard of 347's ? A 60 over 347 is a 352. And can be done with many stock blocks. (D8VE, & Mexican are just two)
I'd definately go check it out. Might just be the timing's off some to prevent it from starting. You can get a rough idea of the stroke by pulling a spark plug and using a dowel or coat hanger wire, down the hole and rolling the crank around a full turn while noting the distance the wire goes down the hole from TDC
Baddad, 351W specs are 3.5" stroke and 4.00 " bore. a .060" over 347 would be a total over-bore of .100" from the stock 4.0" bore. The 347 does not have a 3.5" stroke. They are 3.4" stroke bored .040 over the stock 4".
Do the math again. I've calculated it many times over and a 4.06 bore with a 3.4 stroke is 352 cubes. (2.03 x 2.03 x 3.1416 x 3.4 x 8 = 352.1375) And since when is a .060 overbore equal .120 ?
To get 347" from a 302 you have to begin with a .040" overbore - You said a 347 bored .060 over is 352 - .040 + .060 = .100" You should have said that a 302 +.060 overbore with a 3.4" bore = 352 but it still isn'y to 351 specs - which requires a 3.5" stroke which can'y be done with a 302 without using a deck plate to raise the deck height. Your math is correct - you can get the 352 cu" from a 302 with a .06" overbore and a 3.4" stroke. Your statement that a .060" overbored 347 is the same as a 351 is not correct. I further congradulate you on knowing that a 351W is 352 cu" when stock.
Now you're nitpicking because your were wrong to start with. And just for kicks and giggles, you're wrong again here. A 347's bore is 4.03, not 4.04. And you can also build one now from the new Boss 302 block by boring it 4.125 and using a 331 stroke crank (3.25") And since when does one START with a .040 overbored 302 block and THEN use a 3.4 crank to get a 347 ? If a 3.5" crank is required to get 352 cubes, then explain how a 347 isn't 347 ?
So.... its kind of possible but not a good ideas for a daily driver? Or should I check it out and. See if its just 351 parts? 60 over doesn't sound save to me at all
Nothing wrong with using a 347 as a daily driver. It just depends on how it's built (what parts are used as in heads, cam, compression,etc) I used to use my 331 as a daily driver on a 50 mile (round trip) commute when it was in my 89 Ranger. And that was with the 3x2 carb setup.
