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Posted: Sat Apr 02, 2005 11:06 pm
by Jim K
Ross, indeed in Europe since...forever, the metric notation has been to use the comma for decimals and dot for thousands etc. I had to go the other (your) way when I moved to Canada and revert back to 'ours' when I returned to Greece. What has really screwed things up for a lot of people, is the advent of the Euro. You will see both notations, like 9,95E or 9.95E. Which is right? Well, since we're still metric, money must follow suit and the correct notation is 9,95E. To complicate things, ads in various price lists go either way! Can you imagine someone doing money calculations in Euros and $ at the same time?
One solution is to get rid of any fractions of currency, ie only leave 1E, 2E, 3E etc, but that would create...social revolt, making life a lot more expensive! The 0,01E, 0,02E and 0,05E are useless anyway and there have been proposals in Europe to abolish them. Don't forget that the highly-paid Eurobrains (of questionable contents,possibly fertilizer!), imposed no less than 15 (!!!!!!!!!) denominations on us-UNBELIEVABLY stupid!!!!!
Well, thats it, so much for thread hijack!
Jim K.

Posted: Sun Apr 03, 2005 12:36 am
by Mats
That's the way we write it, plays all kinds of tricks on you when you use US Software I'll tell you...

You will probably write it that way too when you change to the Metric system.

1000000 <- million :P
or
1 000 000 if you have problems with large numbers. :D

I have never understood why the hell anyone would include commas in the middle of one number. This is why stuff crash on Mars you know. ;)

Posted: Sun Apr 03, 2005 2:40 am
by Alfaross69
Yikes I had no idea this would stike a nerve but the thread can bear with us for a moment .
I thought we were changing over to metric 15 -20 years ago it was official and then between the housewives who couldn't put down a measuring cup with avoir du pois measurements and pick up a metric measuring cup and the industrial workers who just refused because they had marginal educations simply wouldn't allow it. Drives engineers, scientific folks,anybody who had metric taught in high school crazy. Mix in a wee bit of nationalism it still hasn't taken hold. the automotive industry slowy incorporated metric bolts into many autos so now its a mix.I guess its just what you learn but I had no idea that there were decimal commas only points. I thought science was an international language and these standards were worked out long ago .very hmmmmmmmm.

Posted: Sun Apr 03, 2005 10:25 am
by Maurizio
:D metric / imperial system. I can write books about conversion hick ups even from suppliers. But back on topic. I used a plexiglas plate and a 5 cc syringe. Combustion chamber where 48,48,49 and 47 cc .

Posted: Sun Apr 03, 2005 12:42 pm
by Jim K
You've just begun to scratch the surface of hard work! Now you must equalize chamber volumes to the largest one by careful grinding. It may take anywhere up to 4 hours and countless repeated precision measurements! When that is done, you must make sure combustion volumes are equal, by bolting the head to the block with a used head gasket and cc'ing all cylinders in turn, with the pistons at TDC of course. If you have any discrepancies there, start crying, because rod lengths will be at fault. When that is also done, you must decide how much to mill off the head for the desired CR and then worry again about how close your valves are to the pistons! :)
Jim K.

Posted: Sun Apr 03, 2005 12:58 pm
by Mats
Damn you're evil Jim... hahaha.

Posted: Sun Apr 03, 2005 11:32 pm
by Maurizio
:D I'm taking a short cut. I have to rebuilt the bottom end. So the rod gets new piston bearings. Machining is measured afterwards, so I can skip that fault factor (goal +/0.01) I will not mill the head. CR will be made with the pistons and then I do not have to worry about the valve reliefs later. But now I worry a lot about valves.....

Piston top of a standard piston is about 0.75 mm above the liner at TDC. Head gasket is 1.8 mm uncompressed. What would be the real height of a compressed gasket. I want move the piston down from TDC to compensate for gasket heigt and measure the secound compound of the cumbustion chamber volume.

:lol: I 've made this saturday a nice fixture to mount and rotate the engine from a (scrapped) IKEA trolly.

Posted: Tue Apr 05, 2005 7:57 am
by TNT
Another big difference with the metric and imperial system is that we in Europe don't say quarter pounter (sp?) with cheese but roayal with cheese(not to mention that in our McD's we can get beer!). :shock:

Posted: Tue Apr 05, 2005 9:52 am
by Mats
Yeah right. Quit quoting movies... :P

Posted: Tue Apr 05, 2005 11:21 am
by Jim K
Maurizio, like I said, do yourself a favor and use an OLD (used!) head gasket for all calculations. To check for valve/piston clearance, rotate engine without head gasket!!!
Depending on maker, head gaskets can compress during use by 0,5mm or more!
Jim K.

Posted: Wed Apr 06, 2005 12:09 am
by Maurizio
JimGreek wrote:To check for valve/piston clearance, rotate engine without head gasket!!!
I 'm using this approach for the piston design. :wink:

Posted: Mon Apr 11, 2005 11:46 pm
by Maurizio
Ok,

I'm looking for some feed-back ... 8)

In the following picture is the timing diagram of the TS cams (motor code 062.24).

Image

My interpretation is that when the vvt is switched, the intake cam is advanced by the the vvt over 32 degrees. Rotational speed of the cam is 0.5 times the crank. So intake cam will rotate over 16 degrees form its marking on the cam cap.

Is my argumentation right?
Does anybody know where the large tolerance (0/- 7 deg) comes from?

Saluti,
Maurizio

Posted: Fri Apr 15, 2005 2:58 am
by Alfaross69
JimGreek wrote:You've just begun to scratch the surface of hard work! Now you must equalize chamber volumes to the largest one by careful grinding. It may take anywhere up to 4 hours and countless repeated precision measurements! When that is done, you must make sure combustion volumes are equal, by bolting the head to the block with a used head gasket and cc'ing all cylinders in turn, with the pistons at TDC of course. If you have any discrepancies there, start crying, because rod lengths will be at fault. When that is also done, you must decide how much to mill off the head for the desired CR and then worry again about how close your valves are to the pistons! :)
Jim K.
Jim
Would you explain how with the head in place how to CC all the cylinders your way.

Posted: Fri Apr 15, 2005 3:04 am
by Alfaross69
JimGreek wrote:Maurizio, like I said, do yourself a favor and use an OLD (used!) head gasket for all calculations. To check for valve/piston clearance, rotate engine without head gasket!!!
Depending on maker, head gaskets can compress during use by 0,5mm or more!
Jim K.
This "go no go method" should tell you that you clear but by how much?
One technique we use is to put "plastilina" or modeling clay on top of the piston and rotate thru a revolution and let the valves imprint the clay. This clearance can then be measured thru the clay with a depth gauge on your calipers

Posted: Fri Apr 15, 2005 3:12 am
by Mats
Alfaross69 wrote:
JimGreek wrote:You've just begun to scratch the surface of hard work! Now you must equalize chamber volumes to the largest one by careful grinding. It may take anywhere up to 4 hours and countless repeated precision measurements! When that is done, you must make sure combustion volumes are equal, by bolting the head to the block with a used head gasket and cc'ing all cylinders in turn, with the pistons at TDC of course. If you have any discrepancies there, start crying, because rod lengths will be at fault. When that is also done, you must decide how much to mill off the head for the desired CR and then worry again about how close your valves are to the pistons! :)
Jim K.
Jim
Would you explain how with the head in place how to measure combustion volume your way.
With a burette. Seal the piston to liner with some grease, torque the head down and fill the combustion chamber through the spark plug hole using a burette, stop when you reach the bottom thread.

That's the combustion chamber volume.