Kpa?!

Discussion on Future Megajolt hardware / software upgrades.

Moderators: JeffC, rdoherty, stieg, brentp

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jetstuff
Posts: 29
Joined: Sun Jun 01, 2008 8:14 am
Location: Norfolk, England

Kpa?!

Post by jetstuff »

hi Brent,
is there any chance of converting the vacuum gauge to Hg (inches of mercury) instead of Kpa??

Thanks

john

MartinM
Posts: 433
Joined: Sat Aug 27, 2005 12:08 pm

Post by MartinM »

...and would you want that in absolute inHg or relative to atmospheric inHg...and positive or negative numbers?

My experience is that Hg figures tend to be relative to atmospheric and although almost always quoted as positive numbers, are actually the amount of "depression" relative to atmsopheric ie a manifold pressure of 2 inches of Hg often means 2 inches of vacuum ie about 29 inches of pressure. Confusing, or what ;)

At least 0-100 kPa is (well, seems to me to be) pretty obvious in terms of which is the vacuum end, even if it's the wrong units.

But having lots of choices in the Configurator (kPa vs. in Hg, absolute or relative to atmospheric, and depression is positive or negative etc) seems a good idea to me as well :)

brentp
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Post by brentp »

KiloPascals was chosen because it seemed to offer a clean transition from vacuum to (optional) boost, depending on the engine's configuration. Most vacuum/boost gauges transition from inches of Mercury to PSI of boost, which would have to be replicated in the gauge (i.e. I'm lazy. :))

But I would agree, more knobs to turn in the software is always good, so I put it on the the wish list. However, aren't we all supposed to be moving to metric? :)
Brent Picasso
CEO and Founder, Autosport Labs
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DannyP
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Joined: Sun Apr 09, 2006 3:48 pm

Post by DannyP »

Wasn't that supposed to happen around 1976 or so?

At least all my tools are metric!

jetstuff
Posts: 29
Joined: Sun Jun 01, 2008 8:14 am
Location: Norfolk, England

Post by jetstuff »

brentp wrote:KiloPascals was chosen because it seemed to offer a clean transition from vacuum to (optional) boost, depending on the engine's configuration. Most vacuum/boost gauges transition from inches of Mercury to PSI of boost, which would have to be replicated in the gauge (i.e. I'm lazy. :))

But I would agree, more knobs to turn in the software is always good, so I put it on the the wish list. However, aren't we all supposed to be moving to metric? :)
I had forgotton that some may be using boost!....my tools are still very much Imperial for this car...(40 year old TR :P )....I'm surprised that USA is going metric too....I can somehow visualise 'inches of mercury' but I have no idea how tall this guy called Pascal was? :wink:

john

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