331 or 347 with trick flow top end

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You will get 20 people argueing now between what is better....331 or 347. Either one will make more power than a 302. Build what YOU WANT TO BUILD. Here's some insight on the two. The 331 has a little better rod ratio which is slightly easier on the cylinder walls, pistons, and crank. The 347 has more cubes and should produce slightly more torque and maybe a little power. Most 347 kits use a 5.400" rod (same as the 331 kits), combined with the 3.400" inch stroke they are forced to use a piston with a very short compression height which means the wrist pin is intruded into the bottom oil ring. Now everybody says they have long since fixed the oil consumption problem but haven't heard any technical detail on how. CHP makes a 347 kit with a shorter rod to used a pistion without that design but then again shorter rod means lower rod ratio. You will also hear people say rod ratio doesn't make a bit of difference, but I think it does for the longevity of parts. In the words of smokey yunick "used the longest damn rod possible".
 
thanks for the insight, I puchased the trick flow h/c/i kit do you thinck it would bolt right up? I guess what my question really is that will ther have to be any clearances made for the pistons and valves , cam upgrades (kit came with the stage 1), or pushrods?
 
A lot of the stroker manufacturers have an optional piston to use with the Twised Wedge heads, I would mention that to them when ordering. Everything else you asked was pretty much block related, and if it is a "roller" block (mid 80's or newer) then no you shouldn't run into any problems. Make sure when you bolt your heads on you put thread sealer on the bottom row of head bolts, as these run into coolant passages and need to be sealed.