Toyota 94 pistons - Hot VW article

[sullydog93]

Is it worth the trouble, probable high cost?

[DarthWeber]

An air cooled piston has different metallurgy, expansion characteristics and dimensions than a water cooled piston...................................then again, maybe Gene Berg was wrong.
_________________

[Fiatdude]

I have aftermarket chevy pistons in mine --- no problems

[Hotrodvw]

I think it's a cool idea, but as the article states, you have to modify them a bit. I'd try it someday!
_________________
'67 Sunroof
Eric

78x94 with IDA's....oober fun

Horsepower is an addiction........Addictions cost
lots of money!

Hose & Fittings

[SRP1]

[mark tucker]

ya Ive been looking at that piston too.and thinking about a 4 or 5 valve set of heads to go with it.
there is no mettelergy to it,just about everybody has a different mix,(alloy)it depends on how you set it up and what the cylinder does.the piston dont know or care WTF it is in. I thought about putting a set of my je 4 1/2"bore pistons in one of my scrap motors just fer the hell of it.might have to split a set of heads to do it, but thats not an issue.

[luckystiff]

there's also the Icon 92mm toyota pistons. forged, no valve reliefs, basiclly C pin height, and fairly reasonable priced. combined with a set of AA thickwall cylinders another very viable option...ken...
_________________
ITMC
Secret Service

[ralf]

[mark tucker]

[tmcdade]

[mark tucker]

looks like a nice piece.my hyd roller cam motor was going to be a small motor(around 2000cc), but things change.I wonder how thick the dome is?it states it is for boosted apps, so it may have some extra under there along with being made right for the app.

[udidwht]

[Fiatdude]

That is true -- BUT aircooled engines run completely different tolerances than water cooled --- It is also true there is a completely different set of op temps in a boost engine vs. an NA engine -- -- if you setup a piston to wall clearance for the application you will enjoy success

[Lobotomy]

Bump. So who here has done this? I read the article, and now I'm really interested in piston alternatives for many reasons beyond them simply being cheaper. I wouldn't really use Toyota 94s in a 1915, due to the high RPMs that it can potentially put out, thus ruining the cast pistons, but what about a Toyota 92mm option for a 2180? You probably wouldn't go over 8k in a well built 2180, so cast pistons are a more viable option. How much machining needs to be done, and where? What cars do the 92s and 94s come out of?

I'm no tuning wizard, but my only fear is that the pistons may expand more than aircooled pistons, in theory, increasing friction, heat and damaging internals faster, but then again, I know dick about this kind of thing, so I'll let you magic men figure it out.
_________________
Vehicles I have:
1974 Super Beetle "Reginald"
1983 AM General DJ-5
1958 Honda c-100

[neil68]

[quote="SRP1"]

[Steve Arndt]

[quote="neil68"]

[mark tucker]

nonsence, not because there forged,in reality they run cooler with less hot spots,but some have an isolation slot and some have holes in the oil ring slot.and there are may different types of aluminum, je had a higher silocon content than sieezco's, & Ive seen a lot more wizassco pistons with broken ring lands too. different pistons take different clearances in iferent applications. a car(wattercooler) bored & honed corectly can work at .0015 with some pistons, now the exzact same motor in a boat will seezzee in a hurry. why??? because the pistons run the same temp in both motors. but the cylinders in the boat have a big supply of nice cool water to keep them cool cool is small, so the piston expands as normal but cylinders dont so they grab each other.,but bearing clearances are about (some .001 more on a boat.)the same as they have hot oil keeping all at the same temp. but there isant a "special"piston for any of it aircooled watter cooled what ever the piston dont care it is going to run about the same temp for it's material(cast or forged, then there is the hyperutectic witch run even hotter) the piston dosent know or care what it is in.

[AlteWagen]

[quote="SRP1"]

[chrisflstf]

The word is... nonsense

[modok]

I think he is looking at a subaru piston probably
The subi piston is very short skirt, the pin is 1mm bigger

the aircooled piston probably does run a bit hotter than some other engines, but not anything that a little extra clearance won't make up for