Cayenne Diesel - Performance Upgrade?
#136
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Been following posts since purchased PO '13 CD 5 mo. ago....great stuff..thx. Installed BS 6 weeks ago. Just did first long trip from central NC to Pittsburgh....515 mi. Got 37.6 mpg in factory setting on way up and 35.1 on return. Main difference was outside temp. 40 degrees lower on return. Make sense? CD performs beautifully, no problems.
#137
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The cooler the air at the intake, the more power is achieved and the more fuel efficiency you will gain. Not to be confused with a cold engine, this applies to internal combustion engines that have already achieved operating temperature.
//greg//
//greg//
#139
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Am on D5 now, rough estimate of 33 mpg in mixed driving. On C9 I got 34.1 mpg on a 220 mile round trip to/from Nashville; 10% metro/30% TLB/60% freeway. Trip computer reflects 30.2 mpg overall since installing BlueSpark 14 months ago. Quite a bit better than the EPA estimated 23 mpg (combined). Having said that, I have a -4.76% speedometer error (indicated vs GPS). Taking that into consideration, the indicated 30.2 mpg becomes a more realistic 28.8 mpg combined. But it's still satisfying when carrying passengers who happen to notice the MFD numbers. Not too many diesel owners among them, so they're usually quite impressed with such fuel economy in 5400 pounds of rolling steel/fuel/occupants.
//greg//
//greg//
#140
Instructor
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I have noticed the Speedo variation as well. I have been doing actual tank mileage measurements and have 28plus MPG on 300to 500 mile fills. I am up to 8900 miles since May. Very happy with the diesel.
#142
Three Wheelin'
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grohgreg, I did see you mention last year filling up with Shell 46 Cetane. Being that our Diesel fuels in general are much lower Cetane rating than Europe's, do you think that could be the root of many of the problems? Especially since mentioned that these companies didn't test with U.S. spec cars whose engine maps are probably tuned to reflect our lower Cetane ratings. Using the higher power settings in these devices are probably overboosting for our quality of fuel but might work just fine in Europe???
Last edited by hahnmgh63; 04-17-2017 at 02:39 PM.
#143
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Any updates on this thread? Current stats?
#144
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Doubt cetane rating is related. But to amplify, I have also been adding Amsoil Cetane Boost at fill-ups; one ounce per five gallons of #2 diesel. Amsoil claims that amount is sufficient to boost cetane 7 points. Between the Bluespark box and the Amsoil boost, I've seen as high as 39.9 (highway) from Minneapolis (MN) to Rockford (IL). I generally drive in Sport mode at the posted limit + 9mph. Over the last 7000 miles, my average mileage displayed by the PCM is 32.2 mpg (combined). City and/or towing mileage is about 24.
At driver-only weight (I'm ~200#), I still make 0-60 right around six seconds. With left foot hard on brake and accelerator floored, the rev limiter holds RPMs @2500. The turbo is then spun up well into its power range. Take foot quickly off brake - and hold on..
//greg//
At driver-only weight (I'm ~200#), I still make 0-60 right around six seconds. With left foot hard on brake and accelerator floored, the rev limiter holds RPMs @2500. The turbo is then spun up well into its power range. Take foot quickly off brake - and hold on..
//greg//
#145
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Greg . . . you still running E8?
I put the Bluespark on our Q5 and E8 made a noticeable difference but there was noticeable increase in turbo lag and increase in diesel clatter on E8 in the Q5. I already have your updated US code from my Cayenne a couple years ago.
My health continued to decline so I sold it and bought the Q5 for the wife. E8 took the Q5 0-60 from 6.5 to 5.7 but I think that would improve noticeably without what feels like a 1/2 second turbo lag hesitation . . . on E8. I tried D9 which didn't have either issue but also did not pull as strong.
Glad to hear you are still kicking!
I put the Bluespark on our Q5 and E8 made a noticeable difference but there was noticeable increase in turbo lag and increase in diesel clatter on E8 in the Q5. I already have your updated US code from my Cayenne a couple years ago.
My health continued to decline so I sold it and bought the Q5 for the wife. E8 took the Q5 0-60 from 6.5 to 5.7 but I think that would improve noticeably without what feels like a 1/2 second turbo lag hesitation . . . on E8. I tried D9 which didn't have either issue but also did not pull as strong.
Glad to hear you are still kicking!
#147
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On the Cayenne, I press hard on the brake, put it in gear, and floor the accelerator. Rev limiter kicks in and hold RPMs at 2500 until you release the brake. It's a 1700 rpm turbo, so launching at 2500 has it already spooled up. I'm curious whether that technique will work on the Audi
//greg//
//greg//
#148
Racer
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On the Cayenne, I press hard on the brake, put it in gear, and floor the accelerator. Rev limiter kicks in and hold RPMs at 2500 until you release the brake. It's a 1700 rpm turbo, so launching at 2500 has it already spooled up. I'm curious whether that technique will work on the Audi
//greg//
//greg//
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2014 991 TT
2013 958 CD
#149
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It will be interesting to see what impacts Porsche's diesel 'fix' will have on low end torque and range.
Also interesting to see what after market tuners come up with.
Also interesting to see what after market tuners come up with.