Does the spots milled out for the valves look correct?
“The bitterness of poor quality remains long after the sweetness of low price is forgotten” – Benjamin Franklin
I dont know if its right but is sure is damn perty.
+1... what pistons did you buy
Not 100% for your engine but it looks about right to me.
Looks like a CP piston . My valve relieves look almost exacly the same.
you can ask for specs from Tony and use a dial indicator to compare.
here are mine
http://www.thesocket.net/build/07302005/100_0474.jpg
http://www.thesocket.net/build/09162005/DSCN0475.JPG
http://www.thesocket.net/build/09162005/DSCN0476.JPG
http://www.thesocket.net/build/09162005/DSCN0477.JPG
Last edited by bmwperson; 01-04-2007 at 01:17 PM.
I've never seen a valve relief cut like that before, doesn't look right but if it is make sure those egdes are real smooth.
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I think the light thats just light, the jagged edge starts where the shadow ends on the upper relief
Should pistons be able to fit in connected to the rod either way? If so, there are 2 different cuts for the valves. One side is cut into the side of the piston and one side is inside the outside edge.
“The bitterness of poor quality remains long after the sweetness of low price is forgotten” – Benjamin Franklin
intake valves are larger hence the difference in the size of the pockets. Can you confirm there are no jagged edges on the piston? or take more pics
I'd not noticed the near side cutouts are totally different to the far side ones in your picture
Im not sure what engine you have but the picture below is from a US M3 turbo CP piston..... *8.5:1 CP ratio*
I would certainly take them to your local friendly engine machine shop and have them check the reliefs against the correct specification that they should be...
There is nothing abnormal about the valve reliefs being asymmetrical, in itself.
Pistons are supposed to go one way, and probably have an arrow of some sort which may point to the front.
Are they supposed to grove like that on the edges of the piston wall? I'll be ordering CP pistons and pauter rods next month.
BTW are those from VAC? And is your set up for the S52 8:5:1?
They are CP pistons from VAC.
“The bitterness of poor quality remains long after the sweetness of low price is forgotten” – Benjamin Franklin
The larger cuts are still smooth despite cutting into the side. Here are some better images per the request.
You can see why someone who wouldn't know better might wonder.
“The bitterness of poor quality remains long after the sweetness of low price is forgotten” – Benjamin Franklin
With those new pictures I would say they are fine.
Especially as they are from VAC. One way fitment.
no problem FTW
The side with the bigger cuts goes on the intake side of the motor.
-Kyle 1995 Custom Turbo M3 SOLD!
Hmmm. These all look similar:
Rob - 2000 BMW Z3 M Roadster | 1986 Porsche 944 5.3L LM4
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