Author Topic: How hard to get 400 hp out of a 400 pontiac engine  (Read 74259 times)

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Offline 72blackbird

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Re: How hard to get 400 hp out of a 400 pontiac engine
« Reply #15 on: December 11, 2008, 12:50:58 PM »
Rain Man,
I was reading that HPP stroker buildup- I personally would NOT use cast rods or hypereutectic pistons on a 462 stroker or any performance buildup, neither are strong enough to withstand 5000 rpm for any sustained period of time. I found out the hard way and it cost me a 406 with a good set of heads. Why anyone would skimp on somethind as inexpensive as forged rods and pistons yet use a roller can is beyond me.

The 380-400 hp 406 in my 'Bird now is coming out for an overhaul/upgrade, since it also has cast rods and stock valves in it. After loosing one good 406 I don't want to repeat the same mistake twice- this motor will more than likely just get a complete rebuild since I'll have to go .040 over and can't reuse the TRWs. The temptation is there to stroke it out to 462 since the machining cost is the same, but I may just go with forged KBs, Tomahawk I-beams, stay with the stock crank and stick a roller cam in this time.

Geno

Offline Rick

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Re: How hard to get 400 hp out of a 400 pontiac engine
« Reply #16 on: December 11, 2008, 09:42:39 PM »
I was reading that HPP stroker buildup- I personally would NOT use cast rods or hypereutectic pistons on a 462 stroker or any performance buildup, neither are strong enough to withstand 5000 rpm for any sustained period of time.

In my recent reading I ran across the recommendation that cast rods not be spun over 4,000 RPM for sustained periods of time, IIRC.  I don't remember where I read that, but I'll keep my eye open and if I run across it again I'll post up the source.

Offline 72blackbird

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Re: How hard to get 400 hp out of a 400 pontiac engine
« Reply #17 on: December 12, 2008, 12:01:25 AM »
I just find it amazing how many professional Pontiac engine builders out there still use cast rods just because the customer is trying to save a little money. Those cast rods might still be good now, but in ten years or so we'll see a widespread epidemic of catastrophic rod failures due to the casrt iron finally reaching the end of its cyclic tensile strength and going brittle, and then everyone will be scrambling to get cast iron rods pulled out of their motors.

Geno