How much hp will a 347 hold?

[deadly97snake]

I'm not talking about a R or a dart block, but a regular 302 block from the factory with forged internals etc...

 

[TrueBlue95GT]

I've heard about 450hp with the stock block, but I may be on crack.

 

[mto502]

I've heard about 450hp with the stock block, but I may be on crack.

I was on the phone yesterday talking to Kennedy Performance in New York and that was what they said as well. That would be 450 rwhp.

 

[94Blue302GT]

Is that with or without power adder? I'd want more than 450 before stuff flew apart

 

[mto502]

With or without a power adder doesn't make a difference. Regardless of if it's normally aspirated or blown the block will handle that much horsepower...... so I've been told.

 

[DavidF]

I was on the phone yesterday talking to Kennedy Performance in New York and that was what they said as well. That would be 450 rwhp.

So thats actually around 540fwhp. given 20% drive train loss?

 

[mto502]

So thats actually around 540fwhp. given 20% drive train loss?

I suppose if you're an automatic I'd go 20% but closer to 15% for a manual, so yes. Sounds like a lot doesn't it?

 

[Babyduck]

turbo... 500-550
blower 450-500

keep the revs low, balanced rotating assymbly, safe a/f, and go easy on the timing, and it'l live a while.

 

[DougNuts]

A properly balance assembly will help it live longer for sure. But like the other guys said, the block starts to flex around 450hp, so I've been told.

 

[67stang390]

I've got a main cap girdle on my stock block. Supposedly, that helps out to equally distribute stress so the block can take a little more power. Who knows how true that is, though. At least that way when I hit it with the squeeze all the pieces will stay together when the block cracks...