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Hey guys,
I'm wondering about the strength of my bottom end. My motor is a 4-bolt main 350 from a early 80's van, its been bored .040 over with sealed power 10.5:1 pistons, i've got a victor jr. intake and am plannig on getting some RPM heads, and a nice cam (any suggestions?) My main question is wheather my con rods and stock crank will hold? i'm thinking about getting eagle stage 1 rods, i'm just wondering about the crank...If anyone has any suggestions that would be great.

Thanks for the help guys!
 

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E.T. divided by $ spent= Speed
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A stock block,crank and rods should be able to handle 400Hp fine,I suggest getting it balanced myself.I wouldn't go reving it into the sky though.
 

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Little known facts about stock durability

I love posting that link.

Yeah stock rods and crank are good anywhere between 5-600 horse. Its not the horsepower that kills a rod (which will be the first thing to go) its the RPM. IF you can keep your R's below 5500 (6k is a strech, no pun intended, but they will start stretching) you'll be fine.

K
 

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Race it, Don't rice it!
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I read the link and disagree with most of it. 600 Horse at less than 5500?. How's that happen? Stock rods are good to 550-600 horse? In a drag car maybe, for I have limited experiance, I do know in circle track they don't last long.

Stock blocks can't handle 450 in circle track application. They break right through the main webs and cam centerline. Perhaps the article was specific to drag racing but they should'nt be making those blanket statements.

I do see some good idea's though.
 

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no, I think you're right john's I think its more talking about a well tuned WOT track motor. It even makes reference to "lasting the season."

As far as making 550 horse below 5500 RPM, I don't think it would happen either, unless you had a big cube motor (bigblocks are not discluded by the article). I would assume they're talking about all sizes of motor with stock rods and crank. A 350 doesn't have to worry about handling 550 horse below 550 RPM, because it would never make the power in the first place. A 496, however, might have to contend with those forces. Anyway, I would assume that's what they're getting at, and yeah, i think its a race oriented article.

K
 

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Race it, Don't rice it!
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I wasn't even thinking big bore engines. They may indeed see those kinds of power levels at lower RPM's. Also, just to be fair, This article was intended for drag racers. For I strongly believe, short tracking is harder on a engine that any other motor sport I can think of right now.

Do you know what pogoing an engine is? It's a term used to describe the rapid up and down RPM changes experienced when a chassis set up doesn't match a rough track condition. Often times the crutch for this condition is a lot of body roll to the right and extreme bar angles in the left rear four links. It causes the car to launch, then land, then launch again on the right side while bicycling, or "two wheelin" as some call it, in rapid succession similar to what a power boat might sound like on really rough sea's. Power boat's have HEAVY flywheels to ease the bending forces applied to the block and crank. Short tracker either use a button with a 3 pound flexplate or a coupler for an auto trans. No converter. The engine takes the abuse rather than the flywheel inertia. Pulling tractor's can also experience the same phenomenon. My point is, it's a great way to break stuff!!
 
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