401 short block

Discussion in ''Da Nailhead' started by 66GSconv., Feb 9, 2011.

  1. gsgtx

    gsgtx Silver Level contributor

    why not give us some facts?? i use them on 2- 440 mopar engines with no problems. also on cold start you wont have piston slap. what part dont you like, the low cost, light weight, better seal, no piston slap or keeping the heat in the combustion chambers ??
     
  2. doc

    doc Well-Known Member

    Yeah, I am intrested in that last statement, because I have used hypers in the last 3 engines that I have built and not had any problems at all....:idea2:
    They seem to be the best cast piston going,,, stronger than stock cast pistons, and the other things already mentioned....
     
  3. Babeola

    Babeola Well-Known Member

    The part where detonation destroys them and your favorite engine at the same time.

    I think thery have a place in engines that are not being pushed to their limit, but you are on the edge of detonation when trying to get the most out of an engine. Our blower engine or any of the other blown 4.6s certainly do not use hypers.

    Cheryl :)
     
  4. gsgtx

    gsgtx Silver Level contributor

    i agree but most nailhead guys are just street cars wanting a little more performance with no power adders. nailheads dont need a lot of timing. also ford uses hyper-u right in there factory engines right?
     
  5. doc

    doc Well-Known Member

    any one that really knows about mechanics will put forged pistons in any engine that sees extreme duty.... huffers, turbos, nitrus, ect all call for forged... and if you drive in places like south texas, florida, all the southern states,,, where heat is a problem in summer, if you want a good , durable engine, you build with forged pistons...but otherwise cast is ok....
     
  6. gsgtx

    gsgtx Silver Level contributor

    i can see guys not wanting to spend close to 1000.00 dollars on forged. but for a extra 50.00 bucks it would be worth it to go for hypr-u and not stock cast, if they had the right pin height. Tom T is running a race car thats a low 11s, high tens which is great times for a nailhead, i can see why he wants forged.
     
  7. Babeola

    Babeola Well-Known Member

    No, they sprung for forged internals in many of the SC models (03-04 Cobra and GT Supercar). The 2012 Boss 5.0 has forged pistons. They are using a powdered metal forging in the GT500 that most serious engine builders are replacing with traditional forgings when increasing the HP levels. When durability and high performace are prerequisites, Ford sprung for forged in the mod motors. They would not have done this unless absolutely necessary. They are very frugal with production costs.
     
  8. gsgtx

    gsgtx Silver Level contributor

    what i ment is ford used the hyper in the 4.6 engines the older ones anyways maybe before 2003 but they did use them
     
  9. wkillgs

    wkillgs Gold Level Contributor

    Joe, both the Silv-o-lite and Summit web pages says those pistons are cast. No mention of them being hypers. Did you find hypers for the Nailhead?

    My knowledge of Hypereutectic pistons is limited to what I've read... they are made of a denser material that is more durable and maintains it's size better under high heat. The downside is they are harder and more brittle....so when they do break, they shatter into small pieces.
    One of my 66's had a 401 with 5 cracked and dented in piston domes....that's an example of how a cast piston may stay together when it goes. A hyper piston would've broken into pieces. It obviously died due to detonation.... Most car guys (and gals) wouldn't treat their car like that!

    I often read online replacement pistons are heavier.....well, not really.
    My stock 401 pistons/pins/rings weighed in at about 950 grams.
    222g of that was the pin, 728g piston.
    The Ross forgings I picked up were still about 947 grams piston/pin but without rings. However the pins are lighter at 159 grams. Piston is about 787g.
    End result is that weight is about the same.
     
  10. gsgtx

    gsgtx Silver Level contributor

    my first 425 piston .028 over was only 711g they are je pistons much lighter than ross. i looked in summit page 138 and they say 16-18% sillcon hypereutectic alloy 30% stronger than untreated alloys.light weight with a high top ring.
     
  11. Babeola

    Babeola Well-Known Member

    Yes and no. The 99-01 NA 4.6 Cobra engine with 300-325 HP used Hyper pistons. They were fine at that level, but do not last when upgrading performance. The 00 Cobra R NA 5.4 with 385 HP used forged pistons. They were actually putting out that much at the wheels. Again, as performance and durability expectations increased, even cheap old Ford went to forged pistons and internals.

    Personally, I like my peanut candy to be brittle: not my pistons. When spending 4-5k on a rebuild, it seems senseless not to spring a few hundred more on pistons that will take more abuse and hold up better in extreme situations. One bad tank of gas could end it for the hypers and my 4-5K engine.

    Cheryl :)
     
  12. gsgtx

    gsgtx Silver Level contributor

    you must have tight clearance more ring gap and not a lot of pinging,ta performnce dont like them and say so in the catalog, and we know Tom dosnt. hughes engines a big mopar builder uses them,also david vizard who writes books and who does a lot of dyno testing says good things about them. if i could choose between cast and hyper with the right pin height i would go with hyper. between hyper and forged and money was no issue i would most likely go with forged.i still think you gain a few hp with hyper but forged is stronger and will give you more peace of mind. in a very mild steet car its almost a toss up.
     
  13. wkillgs

    wkillgs Gold Level Contributor

    K-B Silv-o-lite has a couple lines of pistons.
    -The standard Silv-o-lite is a cast replacement. They make those for Nailheads
    - The KB Performance Piston is the hyper in the Summit catalog. They don't make them for Nailheads, just the 455.

    I used 0.030- over forged TRW's in my first build. Slipper skirt design. Not sure what they weigh, but they 'look' lighter!
     
  14. gsgtx

    gsgtx Silver Level contributor

    my point was the factory did use them, 4.6 in the big fords and lincoln, mercury would go well over 200,000 miles. i know what you are saying and i agree with you.
     
  15. gsgtx

    gsgtx Silver Level contributor

    Walt, sorry i thought the nailheads were hyper i will look on there site again.so we really dont have a choice, stock cast or forged. Ross always was a heavy piston but well made. maybe k-b will come out with a hyper.after all this talk we will all know more about pistons anyways. lol
     
  16. gsgtx

    gsgtx Silver Level contributor

    on the down side forged are 2.5 tmes more money. with forged you can get the right pin height and also the right dome height with deeper valve notchs.
     
  17. Babeola

    Babeola Well-Known Member

    Check with Venolia. They quoted me $696 on custom forged 430 pistons, and they have made custom forged Nailhead pistons for years. Cast pistons are $350-$400. So, it is not that much more for a piston that will meet all of your needs and take on the crappy gas the world offers these days!

    Cheryl :)
     
  18. gsgtx

    gsgtx Silver Level contributor

    for that price you have to go with forged:beers2:
     
  19. gsgtx

    gsgtx Silver Level contributor

    Walt is there a photo of a Ross nailhead piston any place.?
     
  20. wkillgs

    wkillgs Gold Level Contributor

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