Will it HOLD UP?
04-28-2007, 07:34 PM
#1
6th Gear Member
Thread Starter
Join Date: Feb 2005
Location: KY
Posts: 13,396
Will it HOLD UP?
i am going to be building a carbed 347 and am hoping for around 420-450rwhp
then adding a 150 shot. will the block hold up? i am getting a mexican block filling it halfway and girdling it. is the nitrous too much or am i gambling?
also a friend was talking to me and got me thinking about about putting some aftermarket cleavand heads on it. would they be than some windsor heads?
then adding a 150 shot. will the block hold up? i am getting a mexican block filling it halfway and girdling it. is the nitrous too much or am i gambling?
also a friend was talking to me and got me thinking about about putting some aftermarket cleavand heads on it. would they be than some windsor heads?
04-28-2007, 07:57 PM
#8
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Join Date: Feb 2006
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Posts: 5,263
RE: Will it HOLD UP?
1st.: good luck getting 420-450rwhp out of an N/A 347 ( can be done but takes 8,000 rpm )
2nd: yes you will be over stressing a stock block with a 150shot
might last forever, might blow on 3rd spray................
3rd. girdles are waste on a stock block. they do not strengthen the block
they help keep the crank from walking back and forth at high rpm.
putting cleveland heads on is old school trick before we
had all these nice aluminum ones to choose from.
2nd: yes you will be over stressing a stock block with a 150shot
might last forever, might blow on 3rd spray................
3rd. girdles are waste on a stock block. they do not strengthen the block
they help keep the crank from walking back and forth at high rpm.
putting cleveland heads on is old school trick before we
had all these nice aluminum ones to choose from.
04-28-2007, 08:01 PM
#9
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Join Date: Oct 2005
Location: Montreal, Canada
Posts: 8,401
RE: Will it HOLD UP?
it seems you posted it in OT... **** happens.
as for the block, it depends on alot of things, some mexican blocks have held over 800hp for years and are still holding as far as i know, while some have failed at 500hp ...i personally would try to keep it under 600 as much as possible.
as for the block, it depends on alot of things, some mexican blocks have held over 800hp for years and are still holding as far as i know, while some have failed at 500hp ...i personally would try to keep it under 600 as much as possible.
04-28-2007, 08:15 PM
#10
2nd Gear Member
Join Date: May 2006
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Posts: 236
RE: Will it HOLD UP?
+1 on the girdles on a stock block , that is true.
and if i was going to build a nitrious motor, it wouldnt be a 347, because the rotation of the rod (crank)comes to far out, and puts too much pressure on the crank, and the block.
347s (used ) to have problems about thier pistons, oil getting on top of them, but i think they corrected that .
but anyways.. if i had to build a 302 stroker, it would be a 331, they last alot longer.
but so do 351s
and if i was going to build a nitrious motor, it wouldnt be a 347, because the rotation of the rod (crank)comes to far out, and puts too much pressure on the crank, and the block.
347s (used ) to have problems about thier pistons, oil getting on top of them, but i think they corrected that .
but anyways.. if i had to build a 302 stroker, it would be a 331, they last alot longer.
but so do 351s