What does semi-forged really mean?

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Postby vvega » Thu Jan 06, 2005 5:19 pm

hehe ill take some inlet tract pics for ya fivebob

good for a hyjack anyways :D

v
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Postby vvega » Thu Jan 06, 2005 5:41 pm

Image
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silvetop
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and while im taking pics
this ones for bad 20v and all those that really wanna rev to 10k with yur 20v's

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when good retainers go bad
and yes thats what was there on head removal

v
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Postby Dell'Orto » Thu Jan 06, 2005 7:00 pm

Those 2nd pics of blacktop inlet tracts? They look like they've been ported :?

Man, those valves 8O insanity I tell you

(who needs revs when you have torque anyway? :P :lol: )
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1993 AE101 Corolla - Why is this a project now??
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Postby vvega » Thu Jan 06, 2005 7:57 pm

just a little shape changing to get the flow to over the valve rarther than across it(encoraging swirl amd tumble) and to remove the guide that extends down a good 5-6 mm into the flow
the size however remains stock
in all the pics of the blacktop head have been modded
little more smothing of the chamber to be done as well i think
the blacktop head is my turbo one
would have been done somewhat diffrently if it was a N/A head
if you look in my profile there is a pic of the rod and piston combo
the new pistons are dished


have you got any pics of the chamber in that 12psi 11:1 motor you were talking of fivebob i would have liked to have run 10:1 with turbo but for the moment it will be around the 9:1
355 i think you said ??

cheers
v
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Semi Forged

Postby Aging Hoon » Sun Jan 09, 2005 8:18 pm

Hi Five Bob, so weve started this up again a , dont you remember a few years back when Chrysler Valiants had ' HEMI 245 ' on them. These motors were never hemi headed but I suppose it sounded good and fooled a few people. I think semi forged is a similar thing . I dont think you will ever get everyone to agree on this. Im with Dr X FORGED IS FORGED however you look at it. Please dont anyone tell me that the Valiant was Semi Hemi !!
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Postby vvega » Sun Jan 09, 2005 8:42 pm

they are forged
the semi is not indicating it semi forged
the semi solid referance to the metal state when it was forged
if you wanted to be padantic i gues you couldhave the 2
semi solid forged
solid forged
die cast


or you could just drop off the discription of procees and call them

forged
forged
cast

casting is pooring liquid materail into a mold
forged is useing force to make shape out of material

when you hit a peace of metal you are forging it

there are lots of ways to forge somthing

v. forged, forg·ing, forg·es
v. tr.

To form (metal, for example) by heating in a forge and beating or hammering into shape.
To form (metal) by a mechanical or hydraulic press.
To give form or shape to, especially by means of careful effort


v. cast, cast·ing, casts

To form (liquid metal, for example) into a particular shape by pouring into a mold


hope that helps understanding

v
Last edited by vvega on Tue Jan 11, 2005 5:19 pm, edited 1 time in total.
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Re: Semi Forged

Postby fivebob » Mon Jan 10, 2005 12:25 am

Aging Hoon wrote:Hi Five Bob, so weve started this up again a , dont you remember a few years back when Chrysler Valiants had ' HEMI 245 ' on them. These motors were never hemi headed but I suppose it sounded good and fooled a few people.


I agree the Hemi was a marketing exercise, but you'd hardly expect them to call it by it's proper name now would you, some how 245 Wedgie (it was a wedge head) doesn't sound right :lol: BTW my favourite Hemi was the 392 (and also the 426). I used to go down to Bob Clarkson's workshop in the 70's and watch them prepare their 392 powered dragster, sorta got me started on my interest in all things mechanical.

I think semi forged is a similar thing . I dont think you will ever get everyone to agree on this. Im with Dr X FORGED IS FORGED however you look at it.


So what is squeeze cast then, forged or cast? or both? Therefore Semi-Cast or Semi-Forged take your pick. Or I suppose you could use the term Partly-Forged, but I suppose you're too pedantic to accept such a term either.

But like I said before the English language is not so rigid as to dismiss the use of Semi-Forged as a valid term, it is an acceptable description for some processes, just not the ones used to manufacture Hypereutectic pistons for A390 alloys. Calling them Semi-Forged is a misnomer, or more dastardly a marketing term (searches for puke icon...drat none here)
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Postby terrytuffguy » Tue Jan 11, 2005 11:16 pm

http://www.club4ag.com/faq%20and%20tech ... _specs.htm

That oviously states that there are differences between the pistons on the 4agze models. What are they really? I've heard that the ae101 pistons have a ceramic coating also are they semi solid forged like the ae92 ze piston??
My 4AG powered starlet puts out 227rwkw & 12.39 @ 115mph........ YEA RIGHT, Tui.
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Postby Mr Revhead » Wed Jan 12, 2005 9:19 am

the differences are compression
and the early ones do not have slots to clear the oil squirters the later blocks have.
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Postby terrytuffguy » Thu Jan 13, 2005 9:18 pm

according to that website, it's more than just the compression?
My 4AG powered starlet puts out 227rwkw & 12.39 @ 115mph........ YEA RIGHT, Tui.
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Postby Mr Revhead » Thu Jan 13, 2005 9:27 pm

well theres other mistakes there as well....
:wink:

iv had new aw11 pec and ae101 spec pistons side by side. the only real differences are the slots, and the compression.
of course i cant tell the alloy spec from that.
they also have the same forging "grain"
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Postby terrytuffguy » Thu Jan 13, 2005 10:18 pm

Few people have said the ae101 pistons have some form of coating on the top?
My 4AG powered starlet puts out 227rwkw & 12.39 @ 115mph........ YEA RIGHT, Tui.
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Postby Mr Revhead » Thu Jan 13, 2005 10:45 pm

they do. and so do the others
4age has a differnet coating than the 4agzes, dunno what it is though.
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Postby Mr Revhead » Sun Jan 16, 2005 10:43 am

got some pics of a 4agze piston

forging marks

side view

in the side view you can see the coating. also if you look closly you can see the hole that drains oil from the behind the oil rings into the gudgeon pin, and the slots that clear the oil squirters
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Postby terrytuffguy » Sun Jan 16, 2005 3:52 pm

Some form of ceramic coating, has anyone given these pistons some serious amounts of detonation and got away with it??

Detonation might not kill the pistons but still put a huge stress on the big end bearings, headgasket, etc.
My 4AG powered starlet puts out 227rwkw & 12.39 @ 115mph........ YEA RIGHT, Tui.
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Postby Mr Revhead » Mon Jan 17, 2005 8:52 am

detonation will stuff anything in the end.....
best to avoid me thinks! :lol:

fivebob i think has had some experience with toyoya pistons and detonation... farmer dave has as well :?
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Postby Mr Revhead » Thu Jan 20, 2005 11:22 am

and heres some pics of an aw11/eary ae92 type piston....

aw11 side view

aw11 top view

aw11 bottom view note ribbing

aw11 side by side with ae101 you can see the difference in the crown
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Postby terrytuffguy » Thu Jan 20, 2005 7:38 pm

Someone must know what that coating is??

Anyway are the valve recesses there to make it a full clearance motor?
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Postby 10k 20v » Fri Jan 21, 2005 8:27 am

yep
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Postby IH8TEC » Sun Dec 04, 2005 10:56 pm

terrytuffguy wrote:Some form of ceramic coating, has anyone given these pistons some serious amounts of detonation and got away with it??

Detonation might not kill the pistons but still put a huge stress on the big end bearings, headgasket, etc.


hmm, well i've had the detonation, did i get away with it, no, allthough 3 of the pistons withstood alot of detonation, still good apart from rings, but number 2 piston had big chuncks taken off the side etc,

too much boost, not enough fuel, needed rebuilt with 4agze 8.0:1 oversized pistons, wouldn't recomend it, bazda been through same thing. but rebuilt twice i beleive,
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