Hypereutectic vs. Forged Pistons?

So after 1500+ hours and a dead hole I pulled the 351 in my 1987 Martinique this fall. I am at the point I need to pick the rebuild kit and want some advice on hypereutectic vs. forged pistons.   I see pros and cons of each, but wanted some different viewpoints or testimonials.

My recipe so far:

351 Original block
GT40P heads
Edelbrock 2181 Intake
Cam Research 112016 cam
Holley 82670 (670 CFM) 4bbl
Davis Unified Ignition Electric Ignition

All thoughts and advice appreciated.

Hyper will be fine as long as you aren't running on the ragged edge of compression. The material is more brittle than forged or even cast pistons. Detonation is usually the fear on these but I have ran Keith Black Silv-o-lite pistons in my car for nearly 15 years.

That thing has probably north of 200 passes on it not to mention all the unofficial beating. It is around 11:1 compression and detonates like crazy on pump gas during hot weather. No issues ever with the piston material.

You'll want to pay special attention to your compression calculations since you are changing design and combustion chambers. Probably shoot for slightly less than 10:1.

Jonny Quest wrote: I'm not going to weigh in on the piston question...but you may want to look at the QuickFuel M-600 or M-650 carbs. The QF line is like a "Holley on steroids". JQ

You should just change your name to Jonny QuickFuel

Cam Research seems to be like that- I had to call them to find out what a 11283K is. He was not too talkative,I'm guessing because I wasn't buying anything. That would be solved by posting their spec's. He say's they are all custom grinds.

Most Factory engines today that are less than 500 Horse Power are Hypereutectic.
They are very strong but as mentioned they can be brittle on failure.
Drop a valve or bolt on one in a running engine and they will shatter.
If you are over 500 HP or wish to rev over 6,500 RPM I would jump to Forged Pistons.
One other consideration.   If you are building a very high dollar block, maybe for a number matching 67 Corvette go with forged. The forged have some forgiveness in failure that might save that high dollar block from being destroyed.
If a Hyper piston breaks and shatters into pieces the small end of the connecting rod with a piston pin still in it will punch holes in the cylinder walls destroying that number match engine.   
With that said, most OEM engines including Mercury marine, 383 GM engines are sold with Hypereutectic pistons in them, they are very good.
I know Sealed Power tested all the Hypereutectic Performance pistons they manufactured with gasoline, blowers and then with Nitros to see where they would fail.
They did not fail, one big block Chevy ran over 1,000 HP multiple times without failure.
The final test done was to introduce detonation by advancing the timing.   Heavy Detonation finally broke the piston.
Small block Chevy's were tested well over 700 HP on Nitros and up to 6,800 RPM and did not fail.
I still have copies of the dyno testing.
OEM Ford Hypereutectic pistons had to pass the Ford Wide Open Throttle test.   Ford wanted a 300 Hour verified test done with the engine running at it's max Horsepower RPM fully loaded on the Dyno.   Sealed Power did these tests to get Ford contracts.
This data is from testing done in the mid 90's when these Hyper pistons were pretty new.   I can say they were tested very seriously and the quality pretty much eliminated other piston types at the OE level back then.   Some of today's extreme engines are making much higher HP and exceeding 7,000 RPM red lines and use Forged Pistons.
The New Ford Eco Boost Turbo Charged engines are using Hypereutectic pistons made by Federal Mogul/Sealed Power in South Bend Indiana.   The 3.5L ecoboost makes 450 HP with 500 lbs of torque with a V6 and twin turbo's..   
I'm building a small block 400 chevy now with hypereutectics, it will be right at 10:1 compression and make about 440 HP at just under 6,000 RPM and have 500 foot pounds of torque. I am very comfortable with that hyper combo.
Hope this helps.

KENO wrote: Jonny Quest wrote: I'm not going to weigh in on the piston question...but you may want to look at the QuickFuel M-600 or M-650 carbs. The QF line is like a "Holley on steroids". JQ You should just change your name to Jonny QuickFuel

What do you think the "JQ" stands for?

It sounds to me like you did your research.

You say the cam is for reverse rotation from Cam research so you should be good to go.

I don't know if you bought parts yet but gt40KS and you are both in or near Wichita and he's been trying to sell a pair of fresh GT40P heads for a while. They may be on their way to England,based on a recent post but it'd probably be worth checking with him. Might save you some money

Whatever you do, don't take any advice on color schemes from Joe when it comes to painting your engine or anything attached to it   

he'd probably have a good machine shop recommendation though.

So someone earlier asked about the dead hole. It never had any inclination of malfunction other than not registering on pressure test and lack of power. When pulled apart we found about 1/3 of #4 piston was chewed up pretty bad around top edge. Rings and everything were in place and a lot of carbon buildup but otherwise fine. The cylinder itself did not reflect the corresponding damage. Overall I think between the damage to the piston and worn rings there was a lot of blow by..

Don’t worry on the paint scheme we are going back with silver and black.

need a like button on here!

SNobsessed wrote: Maybe the owner of that boat worked at a bowling shoe factory?

Excellent point Chris.

Here’s the deal, I built a 482 caddy motor for my drag car, used KB hypers, opened ring gap up a little for heat, rods are good for 6500, makes great power( 515 hp, 676 ft lbs torque) heck my cc 351 struggles to get to 150 degrees, so, unless your going to spray, stay with hypers, spend the saved money on something else.