Pros/Cons? How will they run with Aluminum heads? 10:1 compression. Possibly a 75 shot? I found a 383 asssembly at www.FlatlanderRacing.com

Scat 9000
I Beams
Hyper Pistons

$539. What do you think?

-Corey

 

Hyper-U's are a little better than stock, stocks on my car were already German higher silicon castings. More resistant to heat but more brittle, easier to crack ring lands especially with Nitrous and any detenation...
I'd go the extra few dollars an geat some inexpensive "Forged" pistons and "H" beam rods. Lighter and stronger than "I" beams, but I've heard late model Powdered Metal rods have good track records, and can be had for a song...
If you shop around you won't have to pay much more than you are looking at now..
Your compression rating of the piston is rated for a certain cc chamber heads, make sure they match..
I'm shopping for a Long rod 383 set up for mine too, "Next winter's project..

 

Why should I look for H Beams? They're expensive! I'm only ever going to put 400hp through this, so won't I Beams be sufficient? Forged pistons in the same kit are only $120 more so I think I'll just save up and do that. Now the combo is...

Scat 9000
I Beams
Forged TRW's

$659

-Corey

 

As long as you're not going real wild, that setup should be sufficient for your 400 hp goal. With the forged pistons it should last through many shots of N2O.

 

I like..

 

hypers will be fine if u arent doing any power adders.

that second setup is what i am going with in my 377 LT1 for my chevelle. good mild setup!!!!!

 

Hyperubreakems won't work with any kind of boost as the ring lands can't take it. Same for detonation.

They are great for N/A and wouldn't hesitate to use them. But like above, I wouldn't use them for any power adder.

 

Decide exactly what your goals are first. If you dont end up using the nitrous, then you may have went with a heavier piston (like the TRW) for no reason. Supposedly, a hypereutectic piston will make more power (NA) due to better sealing and more heat refection into the chamber, its probably a better choice if you dont decide to use the spray. Forged pistons will resist detonation better, and are good insurance if you decide to go with the nitrous.

 

You have to be careful even N/A. I broke 2 Keith Blacks on my 400 tuning the ignition curve. Went just a little too far, got an instant of ping, hasta la vista ring lands. I've had worse ping on sand cast stock pistons with no damage.

Hyperubreakums.

 

That goes for pretty much anything associated with engine assembly and tuning. If you plan on going NA and are on a budget, its difficult to justify paying twice the cash on a set of forged pistons of comparable weight to a good set of hypereutectics. No offense intended but the majority of hypereutectic failures are likely due to user error or improper assembly. A lot of builders dont realize how much heat gets put into the top ring, they dont leave enough gap during assembly, the top ring ends get hot, butt together and then they blame it on the piston when it comes apart. Its similar to the bad reputation N2O often gets, when its done properly it works wonderfully but it only takes a few screwups and subsequent finger-pointing to give it a bad rap.... To imply that cast pistons are better than hypereutectics is ridiculous at best.

 

formularpm, I agree with you to a point. That's why I said, if he's going to use Nitrous, to go "Forged". There are so many things that can go wrong, especially when Mr.Murphy"and his laws kick in. It's one of those,"Pay me now, or pay me MORE later", kinda things.
The fact that the "Hyper's" have way more silicon in them makes them "harder" but more brittle. Anyone knows that good "ductle"(flexible) metal can take a "hit" with less chance of craking.
BUT, BUT, the problem with "cast" is the lower temp resistence, making it easier to "burn or melt" right through them. In that case "Hyper's" are superior..
And then "Forged" offers you the best of both worlds...

 

As an engineering technician/electronics technician/machinist/CAD technician, I often have to read and interpret (and have written) technical instructions. Which is why I was able to set the ring gaps exactly as per the instructions that came with the KB's. Seemed excessively wide, but I did it anyway. I have now come to believe that this is KB's way of trying to avoid a failure that is endemic to these pistons when subjected to any preignition.

Bottom line, of the 20+ engines I've built, the one I used hypereutectics in is the only one that failed. Might be bad luck, might be coincidence, might be that the pistons are a lot more brittle than even sand cast.