How can I tell if these 96mm Arias Pistons are for 1.7/1.8 or 2.0 Options

[jcd914]

I am doing some spring cleaning (IMG:style_emoticons/default/sad.gif) and I am going to sell off some of the excess I have but before I can to that I need know what I have so I can decide if I should keep or sell. About a decade ago I bought a bunch of stuff for a Porsche shop having a yard sale. It was a pile of boxes that they did not want to put back away.
In one of these boxes was a set of new 96mm pistons with bored out 94mm mahle cylinders. I don't know if these are meant to go on a 1.7/1.8 bottom end or if they are for a 2.0 bottom end. I could install one on a partially assembled bottom end but I was hoping someone might know a way to measure and determine.
These are Arias pistons with a dome on them. I don't think I have come across any other domed pistons for a 914 and I don't know anything about Arias.
I have not pulled any of the pistons out of the cylinders yet but cylinder wall look nice and the pistons will move if I push.
Any info would help me.
Thanks
Jim

[SLITS]

If the pistons have a number on them I would call Arias.

PH 310 - 532 - 9737 | FAX 310 - 516 - 8203 | 13420 South Normandie Ave, Gardena, CA 90249

[craig downs]

All the cases from 1.7-2.0 are the same size for the cylinders. On the 1.7 where the
cylinder fits in the head is smaller than the 1.8 & 2.0.

[So.Cal.914]

Isn't the pin placement different?

[SLITS]

Isn't the pin placement different?

Due to the stroke increase, I would think so. The 1.7/1.8 would be the same, but the 2.0 different.

BUT

I don't have a book that gives the piston pin diameter nor the piston pin height.

[Gint]

According to Jake they should fit.

http://forums.aircooledtechnology.com/showthread.php?p=17898

[jcd914]

Thanks for the info everyone.

Yes the wrist pin location has to be different between pistons made to fit a 66mm stroke (1.7/1.8) bottom end and pistons made to fit a 71mm stroke (2.0) bottom end. So I guess I should have just asked if anyone had measurements for piston top to pin a 1.7/1.8 pistons and 2.0 pistons.

I have not net joined Jake's forums so I won't know for a while what he has to say about the Arias piston fit.

Thanks
Jim

[craig downs]

Oops I interpret the ? wrong when I read through it the 1st time.
I don't know the measurement for the pin height but the top of the bore for the pin on a 2.0 is right under the oil ring with a very small gap. The 1.7- 1.8 would have would have a larger gap.

On a 2.0 piston from the top of the pin bore to the top of the piston is .922

Those pistons look heavy

[914werke]

Typically a visual inspection of the piston will tell you.
if the pin position is much lower than the ring lands it is for the 66mm stroke crank
if the pin position is just below the lower ring land it is 71mm

[SirAndy]

Typically a visual inspection of the piston will tell you.
if the pin position is much lower than the ring lands it is for the 66mm stroke crank
if the pin position is just below the lower ring land it is 71mm

This thread is 10 years old ...
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[73-914]

LOL

[ClayPerrine]

(IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-1143-1532116840.1.jpg)

[Robnxious]

[Al Meredith]

real simple! take a standard 1.7 piston and insert a rist pin in 1/2 way, then take the piston in question and insert the other end of the pin in it and if the top of both pistons are the same , it is a 1.7/1.8 . If the piston in question is shouter than 1.7 piston then it is a 2.0.