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Discussion Starter #1
OK,

Various tweaks, findings-out and twiddlings and I'm finally happy with how the old girl is running :D . A long list of stupid things that are here in the forum and I've re-discovered most all of them :roll: .

Just for the record:-

NG900 Turbo. 1997 Trionic 5.


BCPRES7-11 gapped at 1.1mm with 1.1 Bar (16PSI) boost cause a misfire at high RPM most of the time. No problem at stock 0.8 Bar (11.6 PSI) :( .

BCPRES7-11 gapped at 1.0mm with same boost at high RPM misfire some of the time :( .

BCPRES7 gapped at 0.9mm are spottle doodle :) .
 

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Discussion Starter #3
Yep 0.035".


Not 0.040" or 0.044" like it says in my Haynes manual. Fine for std boost, no good for more.
 

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Yes. Simple conversions. 2.54 cm = 1 inch, which means 25.4 mm = 1 inch.

1 divided by 25.4 = .039 inches. Therefore, .039 inches equals a gap of exactly 1 mm. But, you shout, the metric gap should be .9 mm, it says so right here in the manual. Yea verily, for 90% of .039 = .035433 or .035 inches. Learn it, love it, live it. .9 mm = .035 inches. These are the numbers we should all know by heart.

Tomorrow we shall convert weights from lbs., to kilograms & thence to the stone. Bonus points for long and short tons.
 

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Discussion Starter #5
Just stating that the standard plug gap setting would misfire in my car with a higher than stock boost is all.

Haynes, the NGK site, Halfords book and WIS all specify 1.0mm or 1.1mm gaps. I'm implying, from my experience, that either is too large to work on a modified car.

The mm/inch thing I thought was worth persuing because it wasn't immediately obvious to me that; what knowledgeable people have put on the forum here (0.035") is smaller than the 1.0mm or 1.1mm setting you find in UK sources.

For me, the bottom line is: "SET PLUG GAP SMALLER THAN STOCK WHEN BOOSTING HIGHER THAN STOCK"
 

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Saaboheme said:
Tomorrow we shall convert weights from lbs., to kilograms & thence to the stone. Bonus points for long and short tons.
Imagine me trying to participate first time here on MPG thread, converting miles/gallon into litre/km and vv. I had a piece of paper and calculator in front of me all the time.:lol:
 

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Marquis de Saab said:
Imagine me trying to participate first time here on MPG thread, converting miles/gallon into litre/km and vv. I had a piece of paper and calculator in front of me all the time.:lol:
Don't forget MdS: The Brits use imperial gallons, so the calculations are different. That's why whenever anyone asks about what MPG a SAAB should get the UKers always chime in and make USers think that our cars are mistuned.
 

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Hmm, never had my car misfire at stock boost w/ .039. With .044 yes.......035 is a great setting. You may want to try a little ful injector cleaner.
 

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JMarkert said:
Don't forget MdS: The Brits use imperial gallons, so the calculations are different. That's why whenever anyone asks about what MPG a SAAB should get the UKers always chime in and make USers think that our cars are mistuned.
Yup, always on my mind - 3.78 l/gall in US and something around 4.6 in UK... I haven't got the charts in front at the moment.;)
BTW, regarding that misfire, it does sound logical with so much air pushed inside that more quicker and stable spark is needed, definitely on higher RPM.
 
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