Forged vs Hypereutectic piston in daily driver

Looks like my 455 will need a new set of piston. The machine shop is reccomending speed pro hypers for my daily driver. Would this be a good choice? I dont think my power levels or usage need forged. Stock 72 heads and ta212 cam

 

hypers will live a long happy life with that combo. don't boost it or spray it and you'll be fine. you'll need to keep it from detonating as well

 

GM crate engines are making 400+ horsepower from 350 cubes using Hyper pistons...and they come with a warranty.

Hyper is a great way to go for mild-to-moderate builds. They can be sensitive to detonation, but no engine should be allowed to detonate even with forged pistons.

 

Yup hypers

 

Hypers will be fine.

 

All's good with those once the ring land clearance gets checked as being not tight, or not too big.

 

Thanks for all the input. TA is reccomending the forged speed pros for about $90 more. Any downside to going that way?

 

For only $90 more I would get the forged pistons.

 

you need to give them more credit. yes plenty of folks learned the limits of hyper pistons with nitrous and boost but they are not doomed for failure at the first sign of detonation.
they are a good bang for the buck and will be just fine for his application.

 

As long as the engine remains a pure N/A engine with no juice, the Effective Compression remains well within the safe zone for detonation, Hypers will actually provide benefits other piston types won't have.

 

We have used the Keith Black Hypereutectic Pistons in NA 350, 396, 427, & 454 Corvettes, Chevelles, and a 389 GTO with no problems at all.
I have installed a set of them in place of the original 12:1 forged pistons in my '69 L88 crate short block. That engine needed oversized pistons and I wanted to lower the compression to run pump fuel. It's going into my '68 Corvette Roadster with ported large valve oval port heads a comp cams XE-274 cam and the original 3x2 holley tri power. Now I just have to finish the rest of the restoration. Trust me, I don't plan on going easy on that mill.
Once you set the ring gaps correctly you can "give them the beans".
Because you maintain such close piston to wall clearance, ... they are easy on cylinder walls and are quiet too.
Haven't run Hypereutectic Pistons in any BBB's, ... but I wouldn't hesitate for a minute to do so in a street/strip application. I believe when Jeff Donahue ran them in his BBB's he would spray the hell out of those engines and I can't recall him loosing a piston.
They are stronger than most folks who have never used them think.
I do agree that if the price point difference is that close I would opt for the forged also.

Larry

 

8

it all depends on his budget. someone in this board summed it up perfectly once. at the start of the build- "hey that's only 90 bucks" at the end of the build -"SOB another 90 bucks"

 

Stock LS motors come with hyper/cast pistons and seem to do just fine on spray and boost...its all in the tune.

 

If anyone wishes to take the time to look at the latest GM Performance Parts catalog they would find nearly every LS crate motor (with the exception of the LSX BBC) comes with Hypereutectic Pistons, as well as nearly every early gen Chevy small block crate motor in the catalog. That's well over 25 engines. I would be hard pressed to believe all the buyers of those engines are running out to purchase electronic control gizmos because they are worried about damaging their hypereutectic pistons.





Larry

 

Excellent point here. Hidden expenses will emerge when you least expect it, and it all adds up very quickly, especially for those of us who aren't rich...

 

I ran them in a SBC 350 in my Skylark for 10 years before I replaced the engine. That thing ran 115 passes down the track and I almost hate to admit how much I beat on it regularly on the street. For the record, I only replaced that engine because I built a bigger one but that old 350 now resides in a `67 Camaro convertible and he's not going to be any easier on it than I was. As was stated in another post, I haven't ran them in a BBB but I would certainly use them again without worry.

 

I am all for helping reduce costs so that more enthusiasts can enjoy our Buicks and more motors can be built. I recently added a less expensive 4032 material Forged piston to my stroker combo offerings.

That said, I would use cast pistons before I would use hypers. Until you have seen one blown up, you really can't get an appreciation for what a mess they make.

Here's TA's opinion, and why they suggest forged pistons.

You will notice that TA does not list the Hyperutectic pistons. This is for good reason, the Hyperutectic pistons have
additional silicone added to the casting resulting in a stronger but more brittle material, unlike the forging process that
results in a stronger material while maintaining a good degree of ductility. These pistons must be installed with extremely close tolerances
that most engine builders are reluctant to adhere to, any skirt contact (piston slap) with the bore will result in the piston breaking apart and
the debris will be distributed throughout the engine, causing total engine failure. The same holds true if detonation, a lean condition or piston
to valve contact occurs. This design of piston is unforgiving in these situations. Worst case scenario with a cast or forged piston such as the
ones TA offers is a crack or a hole burned into the top of the piston, with very little or no foreign object damage to the rest of the engine.
We Stock Over 200 Sets Of Pistons
For All Sizes Of Buick Engines!


I see a perfectly good running engine come in with Hypers, they are removed and replaced with forged pistons. It's not that I can't successfully work with them, it's that I can't control what happens to the engine when it leaves here.

JW