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In one of my more crafty purchases, I procured what I thought was a set of standard rebuilt 5.7 rods off EBay.

Well, they arrived today and they're for floating pins...I never asked the seller...dumb,dumb,dumb.

Anyway, I've been scouting for pistons and found that KB has reasonably priced hypereutectic pistons that apparently will work with both pressed and floating rods.

Anyone used these? Their ad says the pistons come with the spiral locks, but I don't remember seeing anything about the pins. Would they be different than the pressed pins?

Please excuse me, but I have zero experience with floating rods.
 

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pistons

The KB pistons come with pins, and spiral-locks. The pins are the same for a pressed or floated rods. The rods that you bought are the small ends fitted with bronze bushings???

There are alot of opinions about the KB pistons out there. One thing for sure they will not tolerate and kind of detonation. So you will need to keep a eye on your tune up. The other thing that gets many people in trouble is the top ring gap. Follow there instructions. I actually make my top gaps .002" or so over the top of the tolerance. I have maybe 10-12 engines out there with these pistons and only 1 failure ( because of detonation) I built a 440 mopar with the KB pistons. It's around 525 hp and is now around 3 years old.....still running good....

Keith
 

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K-star is correct, I use the KB hyper pistons frequently. They can be fitted tighter in the bore, but MUST have the end gaps set properly to prevent breaking the top land due to the heat, tighter bore fit, and detonation. I use them in Harley engines with excellent results, but I add .002 to .004" to the end gap as per the chart supplied with the pistons. For higher compression say over 9:1, I add another .001 or.002" just to be safe. (it varies depending upon the bore, larger bores, more gap required)
The only failures I've seen were at a friend's shop rebuilding someone else's work, someone who knows more about end gap than the piston suppplier!
 

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Very good and accurate advice above. I have run them before and have an engine I just sold a friend that is about 5 years old ~475-500HP that has KB hyperutectic pistons.

If you plan to run nitrous I would not suggest them (they can live with about 100HP but, detonation will kill them).

Once again gap your top rings according to your application, they come with a chart that tells you how much end gap you need for different types of engines. Error on the side of too large an end gap. They are very sensitive to ring butting and if the gap it too tight you will break the top off the piston.

I honestly think they are a great piston for the price . They have many good benefits as mentioned above. They are a step above cast and not quite as strong as forged.

I would not shy away from them for a mild to medium performance build.

Royce
 

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I am running KB hypers with the full floating pins. It makes the rods a little heavier, but I think engine wear is reduced.

What is with the "apparent war criminal" caption? Were you up on the stand with Kerry in front of the Senate when he claimed that he, and the rest of the U.S. military were war criminals?
 
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