Building a stroker motor

[Mustang_289]

Well gang - our stang project will be taking on a whole new life in the near future. My son is now wanting to build a stroker motor with using his existing block or getting another block. I remember reading something about only using a certain 5.0 block for stroker motors.

Any words of wisdom on this subject - my son is looking at a 331 or 347. Is there any special work that needs to be done to the block other than buying a stroker kit from someone like D.S.S.?

All suggestions comments are always appreciated!

[90GT398]

I have never heard of a special block to build a 331 or 347. I would definitely make sure the block you are going to use is sound, you know sonic checked the whole 9 yeards. If you plan on turning some high rpm's or hitting it with juice or boost I would invest in a Sportsman or R302 block, or buy a girdle for the stock block, every extra margin helps.

Now FRPP does make a S302 block that is 8.7 inches tall, but there is only one intake I know of that they make for it, and that is the Edelbrock Super Victor 8.7 intake.

[FordMainiac]

i would get a 8.5 block and yes you have to clearence the bottom end so that the rod bolts clear the oil pan rails. And 90GT is right you should have the block sonic checked but also it should be decked and blueprinted. And on a 331 or347 you have to bore it .030 over.

[tarmon8r]

331 has a better rod ratio that an 347 and supposedly will last longer than a 347 due to oil consumption. However, there is some speculation on that part. I have never done a 331 or 347. My question on stroking the 347 is what are you trying to do? Get a 351W? Then why not just put a 351W in it? But then the conversion comes into play. However, if you are building a stout motor, then the cost will be similar.

Then there is the whole stroker 351w combination, but that really comes down to dollars. Because cubic inches costs. Period!!! However, the 393, as you can see that I am partial to, is a good all around combination for a very economical price. As long as your not going to be hammering on it all the time.

They usually recommend late 60's early 70's blocks due to the increased iron content for greater strength and durability. However, the sportmans or R302 would be better upgrades over those. $$$$$$ however. 351 are just bigger and can handle more power due to there bigger journals and size overall. Goodluck with your endeavor. Keep us posted on what you end up deciding. Just trying to share some perspective. Peace.

[USMC302]

definately get the block tested before trying to bore it out, I went through 8 blocks before finding a good one for the project. (I was going cheap, not ordering a R302) Hope it holds up.