What size orifice for leak down test?
04-09-2003, 02:34 PM
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What size orifice for leak down test? I need to do a leak down test on my engine. I'm making up my own leak down tester. What size orifice do I need to create the proper pressure drop through our rings/valves to get the correct reading?
Anybody have a schematic?
Anybody have a schematic?
04-09-2003, 03:10 PM
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Re: What size orifice for leak down test? I was looking at this yesterday. Google is your friend. http://www.google.com
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew
04-09-2003, 03:54 PM
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Re: What size orifice for leak down test? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Camaroholic:
<strong> I was looking at this yesterday. Google is your friend. http://www.google.com
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks! This is what I was looking for in the site you referenced:
"The damper valve
This necessary part is merely a restriction between the regulator and the gauge. The easiest way is to plug the middle pipe with epoxy and afterward drill a 0.040" (#60 or 1 mm drill bit) hole."
Seems to me that .040 thousandths might not be right for all engines. For example you won't get the same pressure loss with a given orifice on a 3" bore, small valve engine as you would on a 4" bore, large valve assuming both are in same condition. I need the correct orifice for our 3.90 diameter bore engine with stock valves. Also flow coefficient of the orifice will vary the indicated pressure drop.
<strong> I was looking at this yesterday. Google is your friend. http://www.google.com
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks! This is what I was looking for in the site you referenced:
"The damper valve
This necessary part is merely a restriction between the regulator and the gauge. The easiest way is to plug the middle pipe with epoxy and afterward drill a 0.040" (#60 or 1 mm drill bit) hole."
Seems to me that .040 thousandths might not be right for all engines. For example you won't get the same pressure loss with a given orifice on a 3" bore, small valve engine as you would on a 4" bore, large valve assuming both are in same condition. I need the correct orifice for our 3.90 diameter bore engine with stock valves. Also flow coefficient of the orifice will vary the indicated pressure drop.
04-14-2003, 01:05 AM
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Re: What size orifice for leak down test? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Camaroholic:
<strong> I was looking at this yesterday. Google is your friend. http://www.google.com
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I finished my leak down test using .040 orifice. I got anywhere from 96-98 % loss throught all cylinders. Looks like my engine is in great shape. I found my plugs to be very black. Looks like my problem is way to rich a mixture.
I also did a compression check while I had all 8 plugs and every cylinder check in at 225 psi.
Thanks Andrew for the lead!
<strong> I was looking at this yesterday. Google is your friend. http://www.google.com
http://www.xs11.com/tips/misc/misc3.shtml
There are a ton of 'instructions' on the 'net.
Summit sells the Tavia checker for $73 or so, and their own brand for ~$63.
I've not decided which way to go.
-Andrew </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I finished my leak down test using .040 orifice. I got anywhere from 96-98 % loss throught all cylinders. Looks like my engine is in great shape. I found my plugs to be very black. Looks like my problem is way to rich a mixture.
I also did a compression check while I had all 8 plugs and every cylinder check in at 225 psi.
Thanks Andrew for the lead!
