[Bermuda Blue]

What is the maximum safe RPM for a 455 using correctly prepared cast pontiac rods with lightwieght components.

Here are the parameters:
1) Rods magnafluxed, polished and shot peened
2) Good bolts (e.g. ARP) installed in rods
3) Relatively lightweigth piston (KB hyperuetectic = 516 g)
4) Lightweigth piston pin (JPB = 134 g)
5) Rotating assembly balanced
6) Rod and main clearance: .0018 - .0022

My guess is that 6000 is the max. since I have seen the same setup using heavy TRW pistons and pins go 5750 with no problem.
I don't plan on revving the motor past 5750.

Should I be safe and buy one of the aftermarket rods and not worry about it?

Thanks for the input

[Bermuda Blue]

What is the maximum safe RPM for a 455 using correctly prepared cast pontiac rods with lightwieght components.

Here are the parameters:
1) Rods magnafluxed, polished and shot peened
2) Good bolts (e.g. ARP) installed in rods
3) Relatively lightweigth piston (KB hyperuetectic = 516 g)
4) Lightweigth piston pin (JPB = 134 g)
5) Rotating assembly balanced
6) Rod and main clearance: .0018 - .0022

My guess is that 6000 is the max. since I have seen the same setup using heavy TRW pistons and pins go 5750 with no problem.
I don't plan on revving the motor past 5750.

Should I be safe and buy one of the aftermarket rods and not worry about it?

Thanks for the input

[slowbird]

I think 6000 is ok just do not do all the time. I had set up like yours but had heavier TRW pistons and a 200 g piston pin. I shifted that motor at 5800 a lot and hit 6000 once or twice and had not problems. I just would not make a habit of doing it because they will not last for long doing that.

[Big Injun]

You didn't say what your primary driving application will be. With the pistons you are using, I am assuming you are primarily using the motor for street driving. If that is the case you'll be fine with the cast rods given you prep them well. Don't over cam the engine (big duration) and it will run well.

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Dave "Big Injun" Anderson
www.PontiacDragDays.com
www.PontiacEnthusiast.com

[Will]

I concur with the above. Install a rev limiter and set it at 6000, just in case. A good rev limiter will actually kick in just before the limit is reached.

[6567GTO]

What do you guy's consider too big of a cam?
Just curious.

Phil

[PONTIAC DUDE]

You forgot the most important fact!!!!! Gear, convertor, and weight. This will put more stress on components then anything. Stock rods will buzz to 6800.....For a while. LOL. But for long life......5400/5600. Besides head flow and cam choice dictate your rpm more then the rods. and a longer stroke sometimes runs faster, short shifting.

------------------
NOS is like American Express.....You don't leave home without it.
http://www.angelfire.com/fl4/pontiacdude428

[zedo]

I turn my 462 with cast rods to 6000, no more.

[Guy Mazza]

Me too....I USED to spin my cast rod/ARP 462 to 6,000rpm now I have a block w/holes in it, a windage tray & oil pan cut that is in half! [img]/infopop/emoticons/icon_biggrin.gif[/img]

[Half-Inch Stud]

12.00 in the 1/4mile, spinning to 4800RPM through the traps. 3.31:1 gear

Perhaps overkill; TRWs on SD rods.

H.I. Stud