Piston Identification Help

[mmt 15]

I need to get new pistons in my mi16. I am not sure which pistons that is installed though. 86mm and a mate says it is std mi 16 2,0 pistons.

 

Anybody have the measurements on std pistons.

[welshpug 1,657]

8 valve, possibly turbo, definitely not any 16v XU as they all have valve cutouts.

[mmt 15]

8v with 86. Mm bore? Are they not 83 mm?

[welshpug 1,657]

alloy ones yes, not the iron block XU10J2 or XU10J2TE.

[dcc 855]

"Piston, this is valve. Valve meet piston."

[allanallen 528 2 Cars]

"Pleased to meet you mrs piston, do you mind if I touch you inappropriately?"

[petert 586]

Very confusing thread. The picture looks like iron block 8V, not either Mi16 version.

[Slo 283 1 Cars]

I couldn't swear by it but they look like my 8v turbo tops when i had the head off. No idea what size they were though

[mmt 15]

It is not the valves that caused the dents. Something was sucked in during rolling Road test.

 

Does anybody have the measurements of the 8v and turbo pistons?

[Slo 283 1 Cars]

Done some reading 8v turbo pistons 85.967mm cylinder bores 86mm

[mmt 15]

Sorry for my late night ignorance In which cars were the 8v turbo pistons used?

 

Does anybody know the pin height of the 8v turbo pistons? I want to be "rather" sure before I buy a set of pistons!

[DamirGTI 342]

Try cleaning up the piston crown surface with an piece of grey scotchbrite pad and some WD-40 .. there should be letter stamp on top of the crown (if it's still present ie. readable).. all the pistons from all the XU engines had letter markings on the crowns from new .

 

If they're 2.0 8v turbo (RGX/RGY) pistons , the mark on the crown should be P or XX

 

Dimensions for 2.0 8v turbo (RGX/RGY) pistons :

 

OD - Bottom measured dia. : 85.970 +/- 0.009mm

E - Distance from the bottom of the guiding pin hole up to the piston crown line : 57mm

F - Distance from the centre of the guiding pin hole up to the piston crown line (compression height) : 40 +/- 0.025mm

 

 

 

 

D

[DamirGTI 342]

Sorry for my late night ignorance In which cars were the 8v turbo pistons used?

 

Peugeot : 406 , 605 and 806 (commonly badged as "SRTi" , "SVTi" or similar)

Citroen : XM and Xantia ("CT" badge for XM , and usually "Activa" badge for Xantia though theres two engines for "Activa" 2.0 T and 3.0 V6 .. an side badges on the front doors should reveal which is which engine wise ..)

 

D

[welshpug 1,657]

Citroen synergie and the fiat equivalent also had these.

 

Afaik they are 152 mm conrods with shrink fit gudgeon pin, that correct damir?

[Slo 283 1 Cars]

Yes 152mm floating gudgeon pin

[DamirGTI 342]

Correct, 152mm says in the book as well .

 

D

[mmt 15]

Thanks guys. Great response. Great help.

[B1ack_Mi16 67]

It doesn't look like a 8v turbo piston really.

 

I thought there were two versions, 1 completely flat top (like T16 ones) and one more or less with the un-symmetrical dish as shown at the top of Damir's picture.

 

I think it might be from another car/engine and not a peugeot piston at all. Unless there are some XU engines out there I don't have seen yet.. could be a possibility that too

[allanallen 528 2 Cars]

What do iron block 8v n/a pistons look like? I thought they had a dish and looked very similar to that?

[B1ack_Mi16 67]

There are some XU10J2 pics here (http://forum.205gtidrivers.com/index.php?showtopic=107352) it seem, and it does look like the dish has the same general shape as in Damirs pic.

[DamirGTI 342]

True , they're a bit weird looking crown shape for stock XU pistons ...

 

All dished 8v XU piston crowns have kinda "bath tub/half moon" dish shape rather than completely round .

 

These ones , if they're not from another engine , might be some aftermarket pistons .. maybe forged "Wossner" "Wiesco" or similar ?! perhaps something like this :

http://www.ebay.co.uk/itm/306-GTi-6-2-0-16V-Grp-A-Wossner-Forged-Pistons-/380317580656

http://www.spoox.co.uk/en/forged-pistons/2427-peugeot-406-20-8v-turbo-pistons-8700mm.html

 

 

D

Edited February 27, 2014 by DamirGTI

[mmt 15]

It might very Well be non PSA pistons. The rods are certainly not PSA. Someone mentioned that it could be BMW M3 or Opel/wauxhall Omega pistons. But from the pictures I Can find I am not really convinced.

Any thoughts?