Triple Bypass - Sounds Serious!
11-28-2006, 12:48 PM
#31
Three Wheelin'
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pzull,
if you cruise on closed throttle, do you pop?
I do, so is that a problem or is it normal to be lean on lift off? (I love the popping, it sounds MEAN!)
My acceleration and general running is all perfect.
if you cruise on closed throttle, do you pop?
I do, so is that a problem or is it normal to be lean on lift off? (I love the popping, it sounds MEAN!)
My acceleration and general running is all perfect.
Last edited by 911addict; 11-28-2006 at 05:49 PM.
11-28-2006, 08:26 PM
#33
Race Car
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I believe most EFI cars including my 3.2 carrera shut off fuel when you lift off the gas above certain RPM. I am guessing the CIS can't do this so I suppose it just leans out the mixture to save fuel. As no power is being produced it should be safe.
Correct me if I am wrong guys.
Correct me if I am wrong guys.
11-28-2006, 09:20 PM
#34
Not Forgotten
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In my understanding the only time a CIS 930/965 is in DANGER from running lean is at WOT, if your car is below 400bhp then the standard (euro) CIS can cope without issue. Above this then the various; fuel enrichment, adjustable WUR, digital WUR, seventh injector, fuel head mod etc are used to get more fuel. With your foot off the accelerator there is little if any air or fuel getting into your cylinders, and also no load on the engine, therefore no knock, no pre-detonation, no problem
11-28-2006, 09:57 PM
#35
Burning Brakes
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Originally Posted by 911addict
pzull,
if you cruise on closed throttle, do you pop?
I do, so is that a problem or is it normal to be lean on lift off? (I love the popping, it sounds MEAN!)
My acceleration and general running is all perfect.
if you cruise on closed throttle, do you pop?
I do, so is that a problem or is it normal to be lean on lift off? (I love the popping, it sounds MEAN!)
My acceleration and general running is all perfect.
However if there is for any reason an overboost situation I would get flames as he tuned in fuel dump and ignition retardation to protect the engine. But it not a situation I am looking forward to
12-04-2006, 09:13 PM
#36
Three Wheelin'
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Talking of POPS.....
I went on a 2 hour run to the PCGB HQ on Sunday and went with another couple of 3.3 turbos :-)
On the way back, as we drove through some villages the roads were very narrow and the sound of my exhaust echoed. It really burbles and pops (& bangs) on lift off. Pedestrians all looked. The 965 behind me said it sounds amazing. He has a G-pipe and now wants the double (cat bypass)....
When we got on the motorway, he heard my Wastegate bypass scream and he wants one of those too!
I went on a 2 hour run to the PCGB HQ on Sunday and went with another couple of 3.3 turbos :-)
On the way back, as we drove through some villages the roads were very narrow and the sound of my exhaust echoed. It really burbles and pops (& bangs) on lift off. Pedestrians all looked. The 965 behind me said it sounds amazing. He has a G-pipe and now wants the double (cat bypass)....
When we got on the motorway, he heard my Wastegate bypass scream and he wants one of those too!
