forged pistons?

mbtoloczko · #1 11-06-2003, 06:09 PM

Everyone says that the SVX has forged pistons, so I went looking for proof on this board and on the internet. I could find no reliable source. Everyone seems to say it as if it were a universal truth. Can anyone point me to a reliable source that proves the SVX has forged pistons?

NikFu S. · #2 11-06-2003, 08:41 PM

how about more and more people saying its true?
forged steel.
ive heard/read this as well. i cant remember where, but i somehow remember it being a true fact.

i also recall the block being forged aluminum. can you forge aluminum?

Mr. Pockets · #3 11-07-2003, 09:07 AM

Quote:

Originally posted by NikFu S.
how about more and more people saying its true?

This, by itself, proves nothing - particularly on the internet, which is like one big game of 'telephone.'

But I'll look in the R&T Guide when I get home - I'm pretty sure it says in there. I know it's online somewhere, but I can't remember where it is.

I just looked around a little and, according to the FAQ, the pistons are forged aluminum. It's not proof, but it helps. I'll keep looking...

Chicane · #4 11-07-2003, 10:53 AM

Quote:

Originally posted by NikFu S.
how about more and more people saying its true?

If that was what we relied on, then we should really be hunting down those twin turbo SVXs.

I also remember the R&T guide saying they were forged, but I could be wrong.

- Rob

mbtoloczko · #5 11-07-2003, 11:12 AM

Quote:

Originally posted by Mr. Pockets

This, by itself, proves nothing - particularly on the internet, which is like one big game of 'telephone.'

But I'll look in the R&T Guide when I get home - I'm pretty sure it says in there. I know it's online somewhere, but I can't remember where it is.

I just looked around a little and, according to the FAQ, the pistons are forged aluminum. It's not proof, but it helps. I'll keep looking...

Yeah, the FAQ isn't authoritative enough for me. If the R&T guide says it, I'm fairly likely to believe its true, but I've seen them make mistakes too. Looking forward to what you find.

Phast SVX · #6 11-07-2003, 11:47 AM

pistons are cast, cobb however offers forged versions

Crank and rods are all forged. Right todd?
phil

Uncamitzi · #7 11-07-2003, 12:10 PM

Why would anyone want to forge pistons? can't you get the originals for less money?

*I know.. that was uncalled for.... especially here....

Mr. Pockets · #8 11-07-2003, 12:18 PM

I don't think that was uncalled for at all, Mitch. I'm kinda wondering what advantages forged pistons have over cast ones, as well. My first guess is strength, but it's not like we see a lot of SVX engine failures.

SVXRide · #9 11-07-2003, 12:38 PM

Forged should provide for increased strength due to the grain structure that results from the forging process (vs casting). Seems to me there was a fairly informative article in SCC (or some mag like it) recently that discussed forged and cast wheels.
-Bill
p.s. I would agree that the stock pistons are probably cast, while it makes sense that the crank is forged. I'd probably lean toward the rods being cast, from a cost standpoint. Todd, or anyone who's torn down one of the 33s would be able to tell us for sure.

mbtoloczko · #10 11-07-2003, 01:30 PM

Quote:

Originally posted by Mr. Pockets
I don't think that was uncalled for at all, Mitch. I'm kinda wondering what advantages forged pistons have over cast ones, as well. My first guess is strength, but it's not like we see a lot of SVX engine failures.

Bill is correct about forged pistons being stronger. Forged pistons are also more wear resistant than cast. Forged pistons are good for high compression motors that are turboed. The likelyhood of the long term survival of a 10:1 compression ratio motor under boost is greatly improved if the pistons are forged.

If someone has an SVX piston they can visually examine, a cast piston may have the following features:

* flashing marks on the backside of the piston (ground down or unground)
* id codes on the backside of the piston are typically cast
* surfaces are usually dull in appearance, especially on the backside

A forged piston may have the following features:

* no flashing marks
* the backside of the piston is typically very smooth and almost shiny
* id codes are forged into the piston

If someone wants to donate a piston to me, I can section it (cut it into several pieces) and perform metallography to look at the grain structure. This is a way to positively tell if a piston is cast or forged.

wawazat?? · #11 11-07-2003, 01:46 PM

Quote:

Originally posted by NikFu S.
how about more and more people saying its true?
forged steel.

i also recall the block being forged aluminum. can you forge aluminum?

Ok, first pistons are aluminum, not steel NikFu. Second you can forge aluminum like you can forge steel. It's a production method that utilizes massive amounts of pressure to form a cold metallic slug or billet into a roughly shaped part. This part is then machined to final dimensions. Casting starts witha molten metal which is poured in to a mold that approximates final shape, allowed to cool, and then machined into its final dimensions. Forging is typically stronger due to a more uniform grain structure in the base metal. Casting produces a random grain stucture and can introduce porosity (bad!) into the part.

Todd

Uncamitzi · #12 11-07-2003, 04:49 PM

Quote:

Originally posted by Mr. Pockets
I don't think that was uncalled for at all, Mitch. I'm kinda wondering what advantages forged pistons have over cast ones, as well. My first guess is strength, but it's not like we see a lot of SVX engine failures.

I was trying to lighten up things as in Forged = Counterfeit....

But it didn't work....

Just like most of my so called humor....

mbtoloczko · #13 11-07-2003, 05:05 PM

Quote:

Originally posted by Uncamitzi

I was trying to lighten up things as in Forged = Counterfeit....

But it didn't work....

Just like most of my so called humor....

Yeah, I got it. I think he did too. :-)

SVXRide · #14 11-07-2003, 08:29 PM

Quote:

Originally posted by wawazat??

Ok, first pistons are aluminum, not steel NikFu. Second you can forge aluminum like you can forge steel. It's a production method that utilizes massive amounts of pressure to form a cold metallic slug or billet into a roughly shaped part. This part is then machined to final dimensions. Casting starts witha molten metal which is poured in to a mold that approximates final shape, allowed to cool, and then machined into its final dimensions. Forging is typically stronger due to a more uniform grain structure in the base metal. Casting produces a random grain stucture and can introduce porosity (bad!) into the part.

Todd

Todd,
So, are you going to put this conversation to rest by providing "ground truth" with actual parts?

-B

Ron Mummert · #15 11-07-2003, 10:42 PM

Quote:

Originally posted by Uncamitzi

I was trying to lighten up things as in Forged = Counterfeit....

But it didn't work....

Just like most of my so called humor....

I "got it", Mitch. In fact, I was about to call in the FBI to investigate these forged, thus obviously fraudulent Fuji imposters. But, you jumped the gun on me.

Ron (twisted minds think alike).