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Posted by: solex Apr 5 2008, 09:01 PM

Anyone know that dish volume for a Mahle Euro spec piston?

Thanks,
Dan

Posted by: Joe Ricard Apr 5 2008, 09:42 PM

Measure it. Just like you do the Chamber Volume.

There is a difference in opinion. but this is what I know and have seen

there is a near flat top piston that is commonly called Euro there is a slight dish you can see with a straight edge.

There is a 3cc dish Mahle Other version of Euro.

There is a 6 cc Dish Mahle U.S
and then a huge dish Mahle like over 10cc Bus

Just measure and calculate your compression ratio.

Posted by: solex Apr 5 2008, 11:30 PM

QUOTE(Joe Ricard @ Apr 5 2008, 11:42 PM)

Measure it. Just like you do the Chamber Volume.

There is a difference in opinion. but this is what I know and have seen

there is a near flat top piston that is commonly called Euro there is a slight dish you can see with a straight edge.

There is a 3cc dish Mahle Other version of Euro.

There is a 6 cc Dish Mahle U.S
and then a huge dish Mahle like over 10cc Bus

Just measure and calculate your compression ratio.

Thanks Joe, I did not measure the volume on the heads but it look like I will need to on the pistons.

Posted by: Joe Ricard Apr 6 2008, 06:20 PM

Yea you are going to learn a lot about measuring before you are done.

When setting your deck aim for .040 close enough to make power and far enough not to be dangerous and crash things.

Posted by: solex Apr 6 2008, 07:09 PM

It is actually the last thing to measure, I was hoping that one of the numbers on the piston would tell me the volume but I cannot make sense of it...

Posted by: solex Apr 7 2008, 04:49 PM

I measured the dish it came up to 2.75 - 3.00 cc's.

Calculating the compression ratio I get 8.1: 1 using a total deck height of 0.60 requiring shims of 0.055 on one side

If I go to a deck height of 0.65 the compression ratio drops to 8.0:1.

Here are my numbers:
Bore 94 mm
Stroke 71 mm
Cylinder chamber volume 56 cc
Dish in Euro Piston 2.75 - 3 cc
Stock Cam
deck height w/o shims
0.005 on one side
0.013 on the other side

New cylinders, pistons rebuild heads and rods.

Now for the questions:
What should I do regarding the shims? I understand that going over 0.60 on a shim is not good, how will this effect my push rods and valve geometry?

One other thing one of the rings is stuck in the landing how to I free it without damaging the landing, ring or piston?

Thanks,
Dan

Posted by: solex Apr 7 2008, 08:25 PM

I free-ed up the top ring, looks like the ring did not seat correctly and dented the landing surface. Should I attempt to clean it up with a file?

Posted by: Joe Ricard Apr 7 2008, 09:24 PM

just my opinion on your deck of .060.

That's a lot of deck. and you will make more power with a bit tighter.

I would be suspect of you measurements if the engine is off that much side to side.

Without messing around with mine it came out .005 difference side to side.

swapping rods and pistons I managed to get it down to a repeatable .002 side to side well with in specs.

Posted by: Jake Raby Apr 7 2008, 09:29 PM

Loose deck= loss of efficiency.

3cc dish= Euro Spec piston
7cc dish- US spec piston
13cc= Bus spec 94mm Piston

Posted by: RJMII Apr 7 2008, 09:51 PM

QUOTE(Jake Raby @ Apr 7 2008, 09:29 PM)

Loose deck

Mr. Raby,

What do you mean by 'loose deck'?

Posted by: Jake Raby Apr 7 2008, 10:09 PM

More than .060

Posted by: orange914 Apr 7 2008, 10:24 PM

QUOTE(solex @ Apr 5 2008, 08:01 PM)

Anyone know that dish volume for a Mahle Euro spec piston?

Thanks,
Dan

mine were 6cc

mike

Posted by: solex Apr 8 2008, 02:09 AM

QUOTE(Jake Raby @ Apr 8 2008, 12:09 AM)

More than .060

Jake do you mean more the .06 on the deck height or more then .06 on the shim. If I go with exactly .060 total deck height I get a compression ration of 8:08:1?

Thanks,
Dan

Posted by: MrKona May 3 2008, 12:10 PM

QUOTE(Jake Raby @ Apr 7 2008, 08:29 PM)