Identify my pistons !

[stalle]

I have a problem to identify two sets of pistons.

I would like to find pistonrings fore them.

The piston to the left I have been told are from a 400 engine.

Dia=95mm
1 groove=1.1mm
2 groove=1.6mm
3 groove=3.0mm
Pin dia.=22mm

The piston to the right I have been told are from a Porsche ?

Dia=97mm
1 groove=2.0mm
2 groove=2.0mm
3 groove=4.0mm
Pin dia.=23mm

Compression height is the same as stock 2.4 and both have been
used in CIH engines.

Has anybody any information or idea where to find pistonrings ?

/Staffan

[jeff denton]

Google "Total Seal" and go their website, there you can find rings by application or dimension. I recommend their "gapless" rings, by the way.

[lamchop77]

Staffan

With regards to the 400 piston on the left it sounds like the gaps are worn by the sizes you have given. Most of the Opel 2.4 pistons i have come across have been 1.0mm/ 1.5mm/ 3.0mm sizes. If you know of a good machine shop you could have the gaps opened up and fit different ring sizes.

I would do as Jeff suggests and look to see what will fit and then if you need to have the pistons modded. I am having this done at the moment on a set of 2.2 pistons.

I would be interested to know what Porsche the pistons on the right came from. If you don't know could you see if there is a part no and make stamped on the piston that i could reference.

Thanks

Chris

[stalle]

Hi Chris !

About the ring gap I haven´t been so exactly with the measurements.
I think you are right there.

About Jeffs link to Total Seal, is there any way to se the measurements
in metric (mm) ?

The "Porsche" piston is a Mahle, I just been told that it was for a Porsche.
I will look for any serial number.

/Staffan

[Hiro]

Originally Posted by stalle I have a problem to identify two sets of pistons. I would like to find pistonrings fore them. The piston to the left I have been told are from a 400 engine. Dia=95mm 1 groove=1.1mm 2 groove=1.6mm 3 groove=3.0mm Pin dia.=22mm The piston to the right I have been told are from a Porsche ? Dia=97mm 1 groove=2.0mm 2 groove=2.0mm 3 groove=4.0mm Pin dia.=23mm Compression height is the same as stock 2.4 and both have been used in CIH engines. Has anybody any information or idea where to find pistonrings ? /Staffan

your left piston is not an original 400 piston IMO.
the 400 engine has Cosworth pistons & Cosworth will not recarve valve notch this way for a group4/B race engine.
I have a set of 400 pistons at home I will dig them from storage & take pics,
by memory they show the Cosworth/Hepolite logo somewhere underside.
Hiro

[stalle]

Hiro:
Thanks for the information. As I wrote, I have only been told
that it was used in a 400.
I can't find any label or numbers.
Do you by recarving mean the valve notch for the 8-valve ?

It will be interesting to se at picture of the real stuff !

The other piston "Porsche" is labeled Mahle 97P12 ++
++
Does that mean anything to you ?

[Hiro]

Originally Posted by stalle Hiro: Thanks for the information. As I wrote, I have only been told that it was used in a 400. I can't find any label or numbers. Do you by recarving mean the valve notch for the 8-valve ? It will be interesting to se at picture of the real stuff ! The other piston "Porsche" is labeled Mahle 97P12 ++ ++ Does that mean anything to you ?

I think the left piston originally was a wedge-type 2 valves like the CIH one,
then the 4 notches for the A400 head were recarved in it.
this piston reminds me about something,
is the cd 31.5mm or lower (about 28.5mm)?
it also seems to be a cast piston not a forged one,
does is show a "KS" casting somewhere underside?
about the right piston I know nothing, sorry.
Hiro

[Hiro]

so here is my A400 piston:
OD 95.5mm
pin 22mm
rings 2/1.45/2.95mm
cd 30.7mm
very specific feature is the L-shape upper ring.

motorist's hand writing says:
95.494
08316.7
26.5.81

stock from the Simon/Clarr racing team in France,
official Opel race team in the 70's & early 80's just before the groupB era.
Hiro

[stalle]

Wow,that was a big differece to my pistons !

Now I know that I don't have a set of 400:s anyway

I have looked closely but can't find any marks, but I'm pretty
sure that the 4 notches are the original ones and the two for
8-valve are made afterwards.

How can I see if it's a cast or forged ? I still hope they could be
useful to some engine in the future if I can find the right piston-
rings. It must have been some kind of hi-perf. because they
have very lightweight cone pins.

Is there any page for TotalSeal with metric measurements ?

/Staffan