forged pistons?

Discuss topics related to the VH41DE, VH45DE, VK45DE, and VK56DE engines.
blownnissanv8
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Hey whats available in forged pistons (high/ low compression) for vh45?I think I might of read a post on this but I cant find it?


sleekster
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Ross will make abut any piston you want for about $800 for the engine and i am sure JE,Dimond and all the rest would be about the same.

blownnissanv8
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thanks

blownnissanv8
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anyone do off the shelf ers?

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car nut
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Not that anyones found over here. Might be different down under.

Q45tech
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Why forged? "A typical forged piston has a skirt clearance of approximately .007 to .009. A cast piston has a skirt clearance of .005 to .007. The COLD Temeprature forged piston has 10 times more slop in the cylinder. This results in less ring stability against the cylinderical wall, more piston noise and extra blowby".

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LEMHEAD16
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I assume by the OPs screen name he is looking at some sort of forced induction.

In just about every other Nissan motor I've dealt with with cast pistons the ring lands are an issue. Forged pistons have more strength in this area and are well suited for FI.

What you said is correct, most forged pistons do suffer from more blow-by and piston slap when cold, but they also have benefits.

I'm sure a cast piston would hold up fine with a perfect tune and low boost.

I was under the impression that the VH already had forged pistons.

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Bart
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But they expand a fair bit when warmed up right?

blownnissanv8
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why forged? cause Im building a methonal burning drag racing engine (1500hp)

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Mettler
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Factory pistons are cast hypereutectic, great for NA application.

gs14racer
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CP piston has them made to order, just call them up tell them what compression you want / bore size etc.. and in two to three weeks you will have them at your door for about 1k.

as to why forged? seriously ? They are superior in strength and reliability in a forced induction application..... to say the least, sure they will slap for a few minute until warm but after that they are fine.

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Bart
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blownnissanv8 wrote:why forged? cause Im building a methonal burning drag racing engine (1500hp)
Are you sticking to stock capacity or stroking the crank?

blownnissanv8
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std stroke crank (I dont want to comprimise the strength of the crank), and at this power level I wouldnt recomend a stroker crank due to the shorter conrods required and therefore increased side thrust on to the bore.If theres a weak point in this engine I would say It will be the bore strength. My block is fully grouted so fingers crossed.


Modified by blownnissanv8 at 4:51 AM 2/9/2010

karay24O
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If you do end up going with CP, you can ask and see if they have the "high silicone forgings." These are slightly less durable than that of the regular low silicone, but have a thermal expansion characteristics closer to that of cast pistons. This meas you can run much tighter and a more constant piston to wall clearance than your typical forged pistons.

They are still a whole lot stronger than any factory piston; however, the only problem I found is that CP does not carry all the sizes in this type of forging.

Edit: Also, many of the Japanese aftermarket manufacturers (along w/ Mahle Pistons) actually use a similar type of forgings. This is why you can run the tighter clearances w/ them.
Modified by karay24O at 9:37 AM 2/11/2010


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