AA forged pistons

[scotth17]

I'm building a 2276 and have just received my 94x82 AA forged pistons. First off, let me say I have never seen this quality at this price. First I weighed the pins and they were within 2/10ths of a gram, good so far, then I weighed the pistons with rings as they came from the bore and cleaned, all within 4/10 of a gram! Then to check ring gaps - the file wasn't touched! I think they have their quality control pretty good now...The only question I have now is how to orient the pistons in the cylinders. The crown is machined beautifully smooth and shiny, with absolutely no markings whatsoever. Everything else looks perfectly symmetrical, so can they go either way in the cylinders? Never seen pistons without any markings...

[VIN]

they can go either direction, they are not offset. however they have extra meat for valve reliefs, and IIRC the valve reliefs go up.
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[bugguy1967]

I find that the quality is really good every time.

A machinist friend of mine told me that he's gone to AA and they have their own machinists in house! Once they arrive from China or wherever, they're finish-machined here. Just what I was told though...
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[rustybusjef]

Make sure the wrist pin are not ofset , my 92x82mm thick walls are ofset as were my 94x82mm but they all had the correct arrows.

[mark tucker]

how thick is the dome(top) just incase I want to add a bath tub to wash my valves.

[fastfil]

Hi Mark,

"Piston top is .250 inches thick, with an extra .100 thou. behind the valve pocket area." (From cip1 website). I could've pulled one of mine out of its barrel to check but I always seem to have trouble getting them back in! The ends of the barrels aren't completely square and the rings seem to find their way into the gap when installing. Yes, my motor is still not together after all this time but I'm still flat out standing at my workbench for 20 mins after last year's back breakage
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"...swingaxle...transaxle...same diff."

[scotth17]

I looked again and mine are perfectly symmetrical inside and out and the underside of the crown is flat....

[mark tucker]

if the under side of your crown is flat it wont fit your avatar........... there probably not forged.
thanks fastfill, dont try to fill that thing so fast, it's easyer on your back. give it some time & dont over do it or you might never getter done as you might never get better if you screw it up again. been there done that got the mri's to prove it.thus my entry into the vw world of light weight stuff.I sure miss using my heavy stuff but cant seem to let it go even though it's in my way & taking up nice airconditioned shop space, lots of it.

[scotth17]

The box says forged...

[esde]

Scotth17, do you have a link to the AA pistons you are referring to? I get confused as they list the "forged" kits as having JE pistons, see
http://aapistons.com/shop/vw-piston-and-cylinder-k...t-191.html
then there is this
http://aapistons.com/shop/vw-piston-and-cylinder-kits-22/94x82mm-2276cc.html
with the Hypereutectic pistons, which are cast.
and then there are these, listed on Johns Aircooled.net
http://vwparts.aircooled.net/Piston-Cylinder-Set-94mm-x-82mm-FORGED-p/vw9400t1sf.htm
they list a slipper skirt. The Hypereutecric $150 set I recently bought also had a slipper skirt and looked nothing like the the piston in this picture
http://vwparts.aircooled.net/Piston-Cylinder-Set-94mm-x-82mm-Machine-In-p/vw9400t1s.htm
So,what's forged? Just the slipper skirt pistons? Just the JE? Does AA make their own forged pistons? I've looked around but have yet to get a clear answer..

[scotth17]

I ordered them from John and they look exactly like the first item listed as JE pistons, but I did not pay $600 for them (I hope)! They are extremly well made from the looks of things, just like those JE ones. The box says 94x82 forged pistons and liners. Maybe I got lucky or something?

[slalombuggy]

My AA's were Forged Slipper Skirt 94s and they had valve relief dimples on the bottom of the crown. VERY nice pistons. I only had to file 2 rings to get the gaps correct.

brad

[mark tucker]

might want to check the ##'s and verify what you have.Ive seen somant cast pistons sold & addvertized as forged. john should be able to identify them for sure by ## & dicsription.

[fastfil]

You're not wrong there Mark. Idle and first gear for me for now, I'll wait a while before running it up the box....

These are my AA forged 94s.

Not to be mistaken for the non-forged ones Pierside sent me originally:

AA might have changed them in the last 12 months.
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"...swingaxle...transaxle...same diff."

[VIN]

pierside sent me cast originally when i bought forged as well.
luckily they quickly resolved the matter, despite being 8 months after i recieved them.
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[77charger]

I just bought some hypertectic AA pistons and cylinders and they are the slipper skirt style.They also have the arrows pointing their direction

94x82s
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[scotth17]

OK, this is what I got:

This is the engine...

[/img]

[esde]

Fastfil, the underside of the wrist pin boss looks to be round, where the forged AA piston that Schotth17 has the pin boss machined flat. So, if they are both AA forged 94mm pistons then maybe something has changed along production. Or, one of them is the JE. Fastfil, is that black area on the skirt a DFL coating you applied or factory? After posting earlier I looked at pictures here and a few other sites, and also see several styles of cast pistons; both with full skirts, and the slipper skirt. Really makes me wonder what's what? have they changed the designs along the way? Supplier? Are the different pistons intended for different applications?

[fastfil]

Esde, yes they definitely look different. Maybe they're sourced from a different supplier now. Hopefully not due to quality issues with my series

They came with the graphite coating.

Mine barely needing touching as far as balance goes. Could have left them as is but got them balanced to +- 0.1 from memory.
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"...swingaxle...transaxle...same diff."

[mark tucker]

fastfill's look just like my cast aa's
scotth's look to be forged, and a nice one at that, but you cant tell by looking . how thick is the dome/head? how much$$ I dont like the hole in the botom of the pin bores. I wonder if it's a je forging?