black924S

Hi. I was wondering if anybody had an OPRV piston lying around that I could get for a song? I can put the spring in and tighten the bolt with no resistance. I think it may have fallen out into the oil pan when I got up to fetch the spring. The oil pan oil went on the burn pile.

odonnell

For a 924S right? I have one from a 1988 944NA which has the same block (someone correct me if I'm wrong, the 87+ block is different as far as 944s go). I have not touched the o-ring on the end, it is intact but you should service it anyway.

black924S

Yes. I had the 3-piece, down to two pieces. Some of these prices are excessive. There has to be a thread on how 944 owners get screwed on part prices. I mean $435 for a new OPRV? The ones for VW aircooled engines cost about $5. I am tempted to just buy a VW OPRV piston and see how it works.

You can buy replacement pistons for 911's (~$15)
You can buy replacement pistons for Boxter's (~$5)
You can buy replacement pistons for VW's (<$5)
You CANNOT buy replacement pistons or old 944's

WTF?

black924S

Going to the salvage yard tomorrow. They have two 944's.

TIP: When paying for a Porsche part at the salvage yard, never tell them them that you pulled it off of a Porsche. Always lie. The part will be much cheaper that way.

ried

Always lie?

black924S

I know. Shameful. They always inflate the prices when they hear the word "Porsche".

xschop

I have another OPRV that is the old piston and spring if you're interested you can have.

black924S

Thanks alot guys for the offers. Luckily, I was able to pillage the scrapyard.They have 2 relatively unmolested 944's. The first one I pulled out a one-piece OPRV with a 25mm hexagonal head. This one is too big to fit fit in my car. The second 944 was a goofy 3-piece. The nut was an INTERNAL hexagon. Never seen that. The spring looked normal but the piston was grooveless. Has anyone seen a grooveless piston? I put that in my car.

Thanks alot for the offer though, I lucked out a the scrapyard. The retrofit 1-piece would have been a better find though.

Tiger03447

Dear Black: You will still need the OPRV alignment tool to install the 3 piece unit correctly. If you want a 1 piece OPRV retrofit unit, you can get one from DIMI 944 at Flyinghorse motorsports..for less $$ than 435.00.

odonnell

For a 924S, you need one from a 1987 or newer car due to the different block design. Someone correct me if I'm wrong

black924S

I "tried" putting the one-piece newer one in just to make sure. It doesnt fit. Bigger diameter.

A 3-piece was in when I got it and it worked
It has a sleeve. I can feel it in the hole.
It is about 63mm deep.
The spring is very tight.

I say without a doubt, it is a 3-piece model.

FRporscheman

I think all the 924S engines are more similar to the "early" 944 engines. I think they all had the 3-piece oprv.

Did you open it up and find out the piston was missing? (If so, WTF?) Or did you just lose it?

You only need the alignment tool if you loosened the oil cooler housing.

black924S

I only lost the piston for the three piece. My car requires the three-piece. The only reason I have a one piece is that I pulled it off of a car at the scrapyard. I also pulled a 3-piece off of a different car. Now I have the 3-piece in my car and and extra one-piece that I have no use for. I have yet to to remove the cooler housing.

My only concern is that the piston(3-piece) nas no groove in it. Every single picture that I have seen shows a groove.

FRporscheman

Interesting, I never noticed that groove before. The turbo engine I'm building right now has the grooveless piston. I forget which piston type is in our '84.

Does the inside of the piston go deep to the groove area or does it stop before? I.e., what's the thickness of the piston at the end? I can measure my grooveless piston, but the end thickness is low.

black924S

Well it's nice to know that I'm not the only one with a grooveless piston. The thing is in my car right now so it's kinda hard to measure.