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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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331 or 347 with trick flow top end

  • Thread starter Thread starter stang_hp
  • Start date Start date Mar 11, 2007

stang_hp

Member
Feb 25, 2007
62
0
6
cartersville Ga.
Mar 11, 2007
#1
  • Mar 11, 2007
  • #1
sorry about posting in the wrong thread, can anyone give me some adviice on what bottom end I should use with my setup?
 

Jason 302

10 Year Member
Aug 9, 2003
685
71
68
Newark, Ohio
Mar 11, 2007
#2
  • Mar 11, 2007
  • #2
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".
 

stang_hp

Member
Feb 25, 2007
62
0
6
cartersville Ga.
Mar 11, 2007
#3
  • Mar 11, 2007
  • #3
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?
 

Jason 302

10 Year Member
Aug 9, 2003
685
71
68
Newark, Ohio
Mar 11, 2007
#4
  • Mar 11, 2007
  • #4
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.
 

stang_hp

Member
Feb 25, 2007
62
0
6
cartersville Ga.
Mar 11, 2007
#5
  • Mar 11, 2007
  • #5
I have also heard of people running into problems with headers on those heads I have BBK do you know if they will work? also does the rest of my bolt ons listed in my sig look ok?
 
R

rickspony

New Member
Feb 22, 2003
6
0
0
4173 beech creek rd rogersville tn 37857
Mar 11, 2007
#6
  • Mar 11, 2007
  • #6
I am running the trickflow heads and have bbk headers bolt right up no problem. Just my opinion but the trickflow heads are a great head you will be pleased.
 
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