For a while now I have been thinking about strokers and witch one is right, the current engine in my 84 F150 is a 5.0 302. I plan on rebuilding the engine in the spring or summer and am stongly considering building a 331. I have given the 347 much consideration but I think for a daily driver the 331 is a better choice. My questions are, what kind of power gains can I expect? I am planning on the 331, a cam, four barrell carb, and true dual exhaust. Also I currently have a 3 speed with over drive stick shift tranny, I will obviously need a new clutch, but what about my current tranny, will I need a new one? Any help would be great, thanks.

 

for the same $$$ you can probably build a 408 if you can get your hands on a 351 W block / intake

 

The gas mpg I would get with a 408 would be horrific, trust me I would love to build a 408, but I need somthing that gets gas mpg that I can afford.

 

Not exactly. The more horses you have under the hood the easier it is to pull the weight around, thus, meaning less fuel for the job. (at normal operating ranges)

408 would be a great match for your truck!

 

To a point; and then you loose efficacy (were that the golden rule, they'd be throwing out 500 and some odd CI BB ford's with HP in the 1000's and getting 732 mpg from the factory... and everyone would have a perma-boner).

You'll make the same HP/Tq per C.I so long as the engines are running all the same gear (valve train, heads, cam... yada yada). Your only difference will be the RPM range; when you stroke an engine, provided the cam remains unchanged, your power band will lower. Example:

302 making 302HP at 4500RPM (1HP/CI)

Built exactly the same aside from stroke would net you about

331 making 331HP at 4100RPM (1HP/CI)

Obviously this is assuming that you've not already maxed out the flow capabilities of your heads and intake before it was stroked... and it's just a general rule with numbers used only for illustration.

To maintain the same power-band you need a bigger cam on a stroked engine. This will also increase your power (duh).

I don't believe it's as big of an issue on the SB ford's, but the mod motors have reliability issues when stroked due to piston protrusion at BDC taking away from the stability of the piston and allowing it to actually tilt slightly in the bore. That isn't to say they last 20k miles and crap on you... you just shouldn't expect 150k miles....

 

yeha I mean i want a good stong reliable engine that puts out some respectable power. It doesnt have to be the most Bad *** truck on the road, but at the same time I want it to be a nice rig. It seems that the 331 is the perfect match for my needs. As for the cam, I have yet to pick out the one that I feel is right. Im looking for somthing that will give me a nice bit of grunt in the mid range area, and will really make my rig sound nice. I was looking at the comp cams thumpr series cams but I am not so sure that that cam series will give me the desired power gains. any of you guys have experience with the thumpr cams?

 

a custom grind cam or one off the shelf designed for a stroker motor will help prevent pumping loss

 

better yet do a mild performance rebuild of a 351W and save a LOT of money.. which will pay for a LOT of gas. Plus it was engineered from Ford for great longevity. And it is a direct bolt in. I doubt any stroker will last as long as a factory spec'd engine as far as stroking it.

 

Thats what I'd do. 351w will last a long long time and they are cheap.

 

Well for one get ride of the 84 block as it is not a roller motor. Get an 85-89 roller block with the forged internals. IMO i would stick with the 302 H.O. and put a good cam and a set of aluminium heads. (Edelbrock performer RPM heads and a Performer RPM AirGap intake, 650 DP)

If you want to stroke it then the 347 is better than the 331. With todays kits theres no issues with the 347's and are just as reliable as the 331 kits.

 

has anyone on the site ever built either a 347 or a 331, If so I would really like to hear what their setup is as far as cam, heads ect...