331 or 347 stroker? pros and cons?

If you use a stock h/c/i the 331 or 347 are a waste of money. the stock hci barely feeds the 5.0. You have to step up the HCI to see the benifit of more cubes, more cubes needs more flow. My CHP 347 dyno'd at 387 HP, with 14 degree's timing,24lb injectors,42psi fuel, TW track heat heads,ported cobra intake and a 65mm TB, 1 3/4 long tubes. We're gonna chassis dyno and tune after its installed to tweak it some more. Oh yea, 10:1 compression, cant remember the cam specs, but lift is in the .580 range with 1.7 rockers. Idle is noticeable at 950rpm, I'll see if I can find the dyno sheet and post more specific #'s
Stock blocks are good to about 500-550hp depending on how well you prep the bottom end(studs and main girdle)
 
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Food for thought :

A friend of mine built a 347 ~ AFR185 ~ RPMII ~ 70tb ~ 75maf ~ 30lb ~ 1-5/8 long tubes ~ Comp XE266HR (216/224 .544/.555 112*w/1.6rr) ~ 3.55s ~ 2.95 T-5 ......

...... He puts 357hp and 351tq to the rear wheels ...... it runs low 12s @ 3068# on 255/45/17 street tires!!

+ he drives it every day with great reliability and no chip!
 
Oil consumption issue is from poor machine work & lack of detail during assembly it has nothing to do with 331ci kit or 347ci kit. My 331ci kit has pin interesecting the oil groove and it had zero oil consumption! A roller rocker broke so I had to tear motor down with just under hard 10,000 miles on it, all parts looked like new...zero wear. Also look at many of the modern day motors that have worse rod ratio's than a 347 yet last 100,000 miles and don't give me the excuse that it's a import motor. There is nothing significantly different, they make the same (if not more) hp/ci and rev the same...so they're putting the same forces on the wall. To get a stroker to last you just have to make sure bore is round.

The only reason I would go with a 331ci kit over 347ci kit is if I had plans for boost for down the road because they have more meat on top of piston or (as was my case) if I came across a deal I couldn't refuse.

350-400 HP should be extremely easy to build with a 331/347, mine idled and had street manners like stock while it made 340rwhp/360rwtq. If you looking only to make 350/400hp there is no need for forged parts. Other than the assembly you'll need new flywheel and damper (28oz).

I do not see the point of building a stroker using mild 302 parts, the gain will be minimal for the money spent.