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Mon Sep 16, 2019 1:44 pm

anyone used non vw pistons in their builds? and if so what'd you use or how'd you find dimensions ?

Mon Sep 16, 2019 2:25 pm

center of the pin bore to the top of the crown is your compression height. VW pin is .866" then find the right piston o.d. the dial point (measurement point) is usually about even with bottom of the pin bore on the skirts. on a standard 332 alloy piston you want about 1.5 thou to 2.0 thou piston to wall clearance... on a hypereutectic about the same.

from there finding rings should be no problem... buuuuuuut. what are you looking for ? there are plenty of already available made for vw options out there.

Mon Sep 16, 2019 2:29 pm

cheap hyper 383 Chev pistons, they were the best pin height to suit a stock type 4 crank . custom cylinders were bored to match .

With a type 1 ,unless you're building a totally different combination it's easier and cheaper to buy piston/cylinder kits off the shelf .

Mon Sep 16, 2019 2:35 pm

I have Turbo Toyota 22R pistons 92mm) 10 over to fit in AA thick wall 92's. I haven't run them yet, still need some motor parts and the interior put in my Bug. With the pin height (can't remember off the top of my head, 22mm?) and an 84mm crank, the engine will be stock width.

Mon Sep 16, 2019 5:21 pm

There was once an article in hotvws about using some 94mm pistons out of another vehicle. Might be worth a search on google.

Tue Sep 17, 2019 6:44 pm

im not really looking for anything in particular, just kicking ideas around.
seems most of the vw pistons ive seen are all flat top and either A or B stroke. so i got to thinking about finding dished pistons for turbo builds or pistons with different wrist pin locations for using with longer / short rods etc etc

Wed Sep 18, 2019 10:29 am

ekacpuc wrote: There was once an article in hotvws about using some 94mm pistons out of another vehicle. Might be worth a search on google.

Those are the 22R pistons mentioned. They come dished, unless you buy forged from ICON.

Wed Sep 18, 2019 10:19 pm

also some pistons from the ford 2.3l pinto engine will work with 94mm I know of a few that put VW pistons in the 2.3l for turbo builds. forged mahle brand.the pin height and diameter is the same or so I was told.

Thu Sep 19, 2019 12:15 am

Some are using Deutz, too, I seem to remember. I once came across some nikasil Oetingers, but they were cracked :cry: :cry: :cry: .

Thu Sep 19, 2019 4:15 pm

Deutz cylinders in a type 4. Never heard of using the pistons. It’s usually in a type 4. And the cylinders get bored for bigger pistons. The diesel pistons probably won’t work well. And nikasil is the coating on aluminum cylinders. I believe ottinger made type 4 ones. I bought a set of aluminum cylinders and pistons from a 911 when I was a kid. Seemed like a lot of work for little benefit. Never even measured the pin diameter to see if it could work.

Fri Sep 20, 2019 6:27 am

there are many, like the 4.6&5.4 ford modular, and the chevy engines with .866 pins and nascar uses a lot of 866 size pins..as does toyota and many others. I have 16 mahle race pistons from roush racing's GTP program ( 24 hour stuff&road race stuff) in 94mm and 94+.003" .also some .001&.002" over sized pins that are tool steel casidium coated( dell west). DSS , manley, diamond have great prices on sets of 8, much better than the vw sets.

Fri Sep 20, 2019 9:32 am

Ebel wrote: Deutz cylinders in a type 4. Never heard of using the pistons. It’s usually in a type 4. And the cylinders get bored for bigger pistons. The diesel pistons probably won’t work well. And nikasil is the coating on aluminum cylinders. I believe ottinger made type 4 ones. I bought a set of aluminum cylinders and pistons from a 911 when I was a kid. Seemed like a lot of work for little benefit. Never even measured the pin diameter to see if it could work.

Thanks for the clarification. The Oettinger cylinders I had were 90mm, type 1. With the 78.4 Okrasa crank, it comes out just under 2000cc.

Mon Jul 13, 2020 11:32 am

Wreck wrote: cheap hyper 383 Chev pistons, they were the best pin height to suit a stock type 4 crank . custom cylinders were bored to match .

With a type 1 ,unless you're building a totally different combination it's easier and cheaper to buy piston/cylinder kits off the shelf . Bumped into this thread after stumbling over some Chevvy 4" pistons on ebay with 12cc dishes.
$180 for a set of 8 with pins and rings. Can that be right?
https://www.ebay.co.uk/itm/NEW-SPEED-PRO-383-SBC-C...SwKQ9aAyEG

4.06" = 103.124mm bore so 103mm barrels could be honed?
Pins 23.5mm could be reamed out for 24mm pins

What's the catch? Small end width?

I know nothing about Chevrolet motors.

Mon Jul 13, 2020 6:11 pm

that's what I run in my 2.3 , except 4.040 " My machinist spun a dish into flat top's . the compression distance ,ie pin to crown is 36.195 which is very close 35.5 standard 2lt piston .

You could get EMW's 103mm cylinders and ask Jorge to hone them to suit the pistons ,though generally a machinist will want the pistons to measure. you are only talking 0.001" to 0.002 clearance with these pistons .
you will also have to get a set of rods rebushed to 23.5mm to suit the pistons .

I would speak to him about what he recommends in your engine . I'm not sure how affected EMW is at the moment in this crazy world but it's only a phone call.
Even though I'm in Australia and EMW is in California ,I found him really good to deal with over the phone and he was very helpful.

Mon Jul 13, 2020 11:26 pm

Wreck wrote: that's what I run in my 2.3 , except 4.040 " My machinist spun a dish into flat top's . the compression distance ,ie pin to crown is 36.195 which is very close 35.5 standard 2lt piston .

You could get EMW's 103mm cylinders and ask Jorge to hone them to suit the pistons ,though generally a machinist will want the pistons to measure. you are only talking 0.001" to 0.002 clearance with these pistons .
you will also have to get a set of rods rebushed to 23.5mm to suit the pistons .

I would speak to him about what he recommends in your engine . I'm not sure how affected EMW is at the moment in this crazy world but it's only a phone call.
Even though I'm in Australia and EMW is in California ,I found him really good to deal with over the phone and he was very helpful.
Great info!
Yes I guess bush the small ends is the way forward. Then I have a spare set of pistons. My rods are H-beam half weight and as I didn't have piston slap and they cost some money I'll reuse them.
There are other chevvy pistons than the one I linked to with bigger and better shape dishes. One with 20cc dish that would allow me to get the CR I want by just unshrouding the inlet.

Think best option for me would be to buy virgin 42/36 heads, chevvy pistons, some barrels and have all the machining and rebushing done locally at one shop.

Interesting, AA 103/4/5 P&C...

Cylinder length 93.5 (AA) - 91.8 (stock) = 1.7mm
Pin 35.5 (stock) - 34.6 (AA) = 0.9mm
Total "extra" deck height = 2.6mm
I believe stock no spacers would be approx 0.5mm deck so 2.6mm + 0.5mm = 3.1mm. At 3.5mm I still can't account for the extra 0.4mm but getting closer and it no longer really matters.

One odd thing I don't understand is the chevvy piston adverts give different "compression height" for same pistons with different length rods...almost like they're measuring from the top of the cylinders. Confusing.

Tue Jul 14, 2020 12:23 am

with a conventional engine you can't space the cylinder out like our engines , so if you go to a longer stroke and longer rods to keep the crank/rod ratio from getting to low the only way to make it work in the same block is if the gudgeon pin moves to the piston crown .

Some pistons have the gudgeon pin level with the oil rings .

Another person to contact would be Jakob at GBT . He does the deutz cylinders and fire rings to help sealing . The Deutz cylinders are not cheap though . But if you can source free or very cheap secondhand ones then they are worth the machining costs ,being secondhand they have been heat cycled and once machined correctly ,will last a very very long time , unless you do something silly or have an accident and drive with no air filters or oil !!

Tue Jul 14, 2020 1:35 am

For type 1, there's many that could work especially if you want to try different engine sizes.. I.e. not just the biggest pistons that will fit...

Look to our Japanese cousins who were building hi rev 16v engines in the late 80s to late 90s..

Mitsubishi, Honda, Nissan all made engines that have pistons that "could" fit... e.g. sr20 depends on what you want to do... if you can find the specs, the right ones can be much lighter in weight, thinner rings, short compression height too...

I don't feel they'll just slip in, you'll have to work for it....

Didn't someone fit 96? 96.5? Porsche pistons to à type 1?!

Also looks like jpm has gone down a similar route with his latest 1600 build! See the "6 valve piston ;)" picture

Tue Jul 14, 2020 2:01 am

Wreck wrote: with a conventional engine you can't space the cylinder out like our engines , so if you go to a longer stroke and longer rods to keep the crank/rod ratio from getting to low the only way to make it work in the same block is if the gudgeon pin moves to the piston crown .

Some pistons have the gudgeon pin level with the oil rings .

Another person to contact would be Jakob at GBT . He does the deutz cylinders and fire rings to help sealing . The Deutz cylinders are not cheap though . But if you can source free or very cheap secondhand ones then they are worth the machining costs ,being secondhand they have been heat cycled and once machined correctly ,will last a very very long time , unless you do something silly or have an accident and drive with no air filters or oil !! I understand moving the pin, A,B and C pistons. But these are a set of pistons and there is no option to actually select a pin height. From the blurb ...
"Specs
Comp Height 5.7" Rod - 1.433
Comp Height 6.0" Rod - 1.13
Pin Diameter - 0.9272"
These ones...
http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?Vie...spheader=1
Though the title does say 6" rods so perhaps the description is used for both these and 5.7" rod version. Must be that?
If so I need to find the equivalent 5.7" rod pistons. I like the look of the dish shape. I don't need valve pockets with a stock cam but they won't hurt anything.

Tue Jul 14, 2020 2:07 am

dunk wrote: For type 1, there's many that could work especially if you want to try different engine sizes.. I.e. not just the biggest pistons that will fit...

Look to our Japanese cousins who were building hi rev 16v engines in the late 80s to late 90s..

Mitsubishi, Honda, Nissan all made engines that have pistons that "could" fit... e.g. sr20 depends on what you want to do... if you can find the specs, the right ones can be much lighter in weight, thinner rings, short compression height too...

I don't feel they'll just slip in, you'll have to work for it....

Didn't someone fit 96? 96.5? Porsche pistons to à type 1?!

Also looks like jpm has gone down a similar route with his latest 1600 build! See the "6 valve piston ;)" picture
Personally I'm rebuilding what is already a 104mm piston engine. At around 4" the choice is quite limited. Type-1 folk have a multitude of options actually aimed at them though, much easier in that respect but generally a lot more work and parts to build a large capacity motor than will push a 2 ton bread loaf without over heating.

Tue Jul 14, 2020 4:26 am

https://www.thesamba.com/vw/forum/viewtopic.php?t=728801&highlight=nissan+pistons