I would go ahead and do the 347. The rod ratio is still better than the old big blocks (454, 427 etc). Some are advertized to go 100,000 miles on the street now. But I dont see why your going with a stroker before you do your heads and intake. You maybe really impressed with your car after that. Unless your planning to do it all at once.
Im still up in the air on 351 or 347 myself. The price of the swap is almost the same either way.
Sky
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-1989 Saleen Mustang #406- TFS Heads, E-303, edelbrock intake,70MM TB, 73mm MAF, off road H, headers and 3chamber flows.
12.55@107mph
Runs on 87 Octane and gets 24mpg!