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Discussion Starter · #1 ·
Does a 393/408, (351w stroker) need forged pistons? I was thinking of just putting in some good hypereutectics pistons in (keyword: *good* )

The Ford crate motor uses hyper. pistons as well :D
 

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Good hypers with a proper tune are capable of lots of things... but there are depends to the situation. There is the potential for casting porosity and or fragileness of the pin boss area when we are talking about extreme loads.

If your talking about a similar head combo, and your comparing the differnt strokes, you will net more HP at lower RPM and have less destructive force all around. But if your talking about adding the head and cam to the larger stroke engines to turn the RPM to make HUGE hp.... then piston speeds and the forces trying to jerk the pin out of them rise exponentially.
 

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There is absolutely, positively nothing wrong with hyper pisters what so ever. They are wonderful. Don't listen to the idiots on this board who talk smack about them and have no idea what hypereutectic even means. If you are planning nitrous, you may want to think about using forged. If you are planning a turbo or blower, it all depends on your compression and intended boost levels whether you really need forged pistons or not. If you are building a N/A stroked 351, don't let anyone sell you forged pistons unless you really want forged pistons. Make sure they are smart enough to give you a scientific reason why you need them. Good luck with your build. Maybe someday I'll be able to afford the big stroker. Lots of fun it will be.

Glad kim jumped on this one first. I get real tired of the spam that usually begins these type of posts.
 

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Discussion Starter · #4 ·
Thanks Kim and Grey,

the engine will be mainly street driven, and usually will only reach 5500rpm or so max, and seldom see 6000k or so.

So I should go w/ the Keith Black pistons then? :) or are there better hyper. pistons?
 

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why spend the money to swap to a 351, stroke it, but then skimp on pistons? doesn't make any sense to me
 

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For non power adder engines hypereutectic pistons are actually better than forged, yes not as strong but also don't expand as much so you can run a tighter p-w clearance. They are not as ductile as forged so if you plan to spray you will have to go with the forged.
as for hypereutectic being a "skimp" ...The process was invented by cosworth for their race engines, pretty stout pieces if done right.
 

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In this situation, I don't think this is a "skimp" in any way.
 

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No spray, no boost, no problem....
 

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Discussion Starter · #9 ·
ok,

I'd like to build a stout lower compression 351s stroker shortblock later for a turbo, so this one is non-turbo (non-power adder), and the next one will be boost city :)
 

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Go Forged... You'll be glad you did.

Spend the extra $150 or so bucks and get them...


I've seen too many wrist pins rip out of Hyper. Pistons..


:barf: Crappereutectic
 

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Save for the forged pistons. If you ever kiss a valve you will truely understand. Cast and hypers explode and offer little to no protection to that rod that doesnt have time to stop as it punches a hole in your block and makes waste of the complete motor. Is this worth a couple hundred? I think not.
 

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DSS Mikes Nice Forged Pistons..

They have the Pro-Series (Budget) Pistons for $299
These will BLOW the Kbs out of the water....
For $75 bucks more than the KBs.


Then they have the Pro-lites, Which are there Top line pistons.
60Grams lighter than the Pro-Series. $499

www.DSSRacing.com
 

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Man, these guys are right. Save your money and buy some really really really really really really really good pistons. Personally I wouldn't run anything less than a Ross piston. Hypereutectics rip out rist pins all the time. Hell I had to replace 2 pistons last week on my truck. I was driving the other day and I heard this ripping noise. I thought to myself, I should have listened to all those corrallers with so much bench racing experience it makes my head spin. I'm replacing pistons in my truck one at a time with Ross pistons as they rip out. Yeah it vibrates now, but as soon as all the hypereuwhateveryouguyscallthem pistons rip the rist pins out like tin foil, it will run smooth and never ever blow up. Actually forged pistons are so good you won't even need a crankshaft. These pistons are so good they actually stay in the bores and make the flywheel so happy it just spins like a rotory engine.

There, I joinned in the spam, and mine is actually believable............:rolleyes:
 

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Discussion Starter · #14 ·
lol, hypers w/ this engine

wouldn't the KB pistons be lighter than the DSS $299 forged pistons?
 

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If you go on the KB site, they list all the weights of the different part #'s.


I was reading the "one at a time piston replacement" post and was like......WTF?????? then I caught on. :lol:
 

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Pushed Hypers to almost 540hp with a 150 shot of N2O in a balanced 306 that would see 7500 RPM.... at the track, and drive to work every day for over 5 years. Had a N2O leanout... and blew the top off one.... I had a mechanical failure,,, gas solenoid didn't open. And that was the end of that.

We put Speed pro's in lots of high end street stuff. Most of the pistons are real nice, they are comming out of the box within a gram of balance. (I still even them up, but compared to TRW stuff, the average backyarder could consider it a matched set out the box) They have a diamond cut top, a dryfilm skirt coat. We can put them in the bore and run .003 skirt clearance. Low tension rings reduce engine friction, yet have great support so they function equal to a high tension ring for cylinder seal and oil controll.
 

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Its called insurance.
I didnt say the wristpin pulled out of any I used but I seen a dropped valve ruin a Boss Block. Im pretty sure the dropped valve head would of stuck into the face of the forged piston as Ive seen pictures of b4 instead of grenading the piston and ruining the block.

Why even use any hipo parts. Autozone motors are plenty good just slap on a YS trim or 100MM turbo or 500hp N2O kit :rolleyes:
 

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There are a lot of high quality forged pistons out there to choose from. Personally I like the SRP/JE pistons. I have been in the high performance business for 30 years and have had literally hundreds of customers as a "database" from which to get real world feedback on pistons. Guys like GreyLX are always around screaming that they are the "source of all knowledge". That's just fine, but they try to drown out common sense. Hypereutectic pistons have been around a long time. So has McDonalds, but few would say they make the best burger. The interest in hypereutectic pistons, historically, has been due to the lower cost. Clever marketing with the Keith Black name has convinced some that this must be a "hipo" piece. Back in the sixties and seventies ALL top factory engines used forged pistons. Boss302, 427, boss429, Z28, L82, LS6, 426hemi, the list goes on. In the 87 5.0 thru 92, they all had forged pistons. Bottom line is that hypereutectic pistons are very brittle vs forged and it does not take much in the way of abuse to get them to literally fall to pieces. In a low stress environment they may be okay, but ask yourself how much money you will have invested in your engine and will that extra $200 truly be a hardship. Good luck
 

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mopacmach,

Never said I was the source of all knowledge. I haven't yet build a 9 second engine. But I have read more posts on hyper pistons than I care to remember and I'm really tired of the missinformation about hyper pistons. You guys building all out race engines, that's one thing. Most people on this forum do not, but thanks to bench racers, they think that hyper pistons are worse than plastic pistons. It's stupid and misleading. I run forged pistons in my 306, but I planned a blower combo at the time of purchase. I'm planning a stroked 351 in the future and may use hyper pistons depending on budget and what I can find at the time. Being forged is definitely not my deciding factor at all for a N/A combo. I did a lot of research on pistons, enough to know that Ford NEVER put a true forged piston in any H.O engine, something most people will argue until they are blue in the face. I don't mind being flamed for my views either. Just don't be biased for no good reason other than internet rumors.
 
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