Just moved from Dallas to Denver, Colorado, and I notice that in first gear, my 2000 Infiniti I30t doesn't pick up power until 3000 RPMs. Seems to have a big power surge at 3000 RPMs.
It only does this when I'm in Colorado, and not in Dallas. I've noticed this since I've done several trips back and forth between both cities.
Two differences, the octane of the premium gas in Dallas is 93 while it's 91 here. I know that they use lower octane gas in higher altitudes. Can this cause the low power / surge at 3000 RPMs in first gear?
Since I'm now a permanent resident in Colorado, is there an adjustment that has to be done for the higher altitude?
Any ideas on what I should do?
Thanks.
Car Info:
2000 Infiniti I30t112000 MilesRegular Oil Changes with Mobil 1 oilAlways used premium gasRecently change out spark plugsReplaced air filter about 1 month ago.Located in Denver, Colorado.
Altitude Adjustments?
There's no adjustments necessary. The mass airflow sensor measures the air correctly in both locations. 93 octane is less prone to knocking, but the knock sensor will back off timing if necessary to compensate.Short answer is that the car has a lot harder time breathing up there, just as people do, so sluggishness is to be expected. I remember the performance difference clearly on my trips to Boulder.
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (DAEDALUS)
Unfortunately the weather reports are not REAL but locally corrected barometer [for altitude]. Each 333 feet is 1% less dense, thus the BMEP is 1% lower. Torque is a direct function of BMEP. Compression ratio times air density x air amount volume>>>>>> yields peak pressure after/during the burn peak [15-17 degrees after top dead center of the piston position].
The rod angularity must be just right to create max torque [twisting motion on the crank] not too early to drive the crank via rod into the bearing......or just to late to exert maximum moment of force.
See what ignition advance retard does........max pressure at just the absolute right moment in time to turn the crank not beat it to death with preignition/knock abnormal operation.
OEM timing is ALWAYS on the conservative side by a lot to increase bearing life and engine longevity.
Unfortunately they cannot guess what REAL octane the fuel is at that one moment in time..........thus knock sensors and a kind of short term accumlative learning in ecu. AND some extra backoff just in case for dirty combustion pieces worn plugs etc.
Each 1000 feet above AMSL can allow a 0.9-1.4 octane point reduction in requirement. Denver in theory [at 68F] could allow a 4.5-7.0 drop in octane but..........the refineries take this in account to save money and use NATIONAL LABELS to avoid confusing public. They juggle the research vs motor octane components to further minimize cost [a point in the motor test cost 1-2 cents more per gallon to make than a single point in research test]..........fill up in Denver or other high place and drive to a lower altitude and more heat ------ping/knock city if your engine is sensitive.
Atlanta at 1000 feet labels 91+ as 93 because it acts that way in a special temp test at 68F but in Summer heat may not test above 91. Rarer to see 93 at warm sea level cause it doesn't exist.
There really are only 2 grades of gasoline produced [fungible regular and fungible premium] with differing Reid vapor points and some emission tricks for EPA zones. Since ethanol cannot be transported by pipeline [picks up the water in lines used to divide the batches]. Splash blended in at local depot.
MTBE oxygenated gasoline could/can be transported via pipelines......so actual 4 types might be around raw reg and raw premium, then MTBE reg and MTBE premium.
Did some testing [this month] on 89 vs 93 as long as the temp was below 50F fine, Q rattled like hell at 60F on 89 [QT retailers]..........it took a can of BG44K or 2 full tanks of 93 to get back to normal after a single tank or two of 89.
Save a penny making a million gallons a day means $10,000 per day x 365 days.......some real money to the bottom line.
The blending chemist/the blending computer engineer........running on the ragged edge of knock to keep their jobs and maybe get a tiny bonus.
"Lets see this load is going to a cold high altitude place [will it be warm or cold the day it's used by the engine].....I'm going to save a $1,000 bucks and make the higher ups happy ........unfortunately who knows it might get diverted to somewhere else along the pipeline.
You really cannot trust the pump labels everywhere on every day as the hourly mix changes constantly.......and by the time it gets to filling stations it has interreacted for days......weeks plus the time in your tank.
The salvation is that different 10,000, 100,000 gallon lots get blended together in the giant holding tanks [local big city tank farms] where the pipeline water slugs get separated out.......kind of like cows milk by the gallon.........a little bit of each cow included. Hope mine wasn't sick that day........takes a lot of young kids in a swimming pool to make it unsafe for swimming.
The rod angularity must be just right to create max torque [twisting motion on the crank] not too early to drive the crank via rod into the bearing......or just to late to exert maximum moment of force.
See what ignition advance retard does........max pressure at just the absolute right moment in time to turn the crank not beat it to death with preignition/knock abnormal operation.
OEM timing is ALWAYS on the conservative side by a lot to increase bearing life and engine longevity.
Unfortunately they cannot guess what REAL octane the fuel is at that one moment in time..........thus knock sensors and a kind of short term accumlative learning in ecu. AND some extra backoff just in case for dirty combustion pieces worn plugs etc.
Each 1000 feet above AMSL can allow a 0.9-1.4 octane point reduction in requirement. Denver in theory [at 68F] could allow a 4.5-7.0 drop in octane but..........the refineries take this in account to save money and use NATIONAL LABELS to avoid confusing public. They juggle the research vs motor octane components to further minimize cost [a point in the motor test cost 1-2 cents more per gallon to make than a single point in research test]..........fill up in Denver or other high place and drive to a lower altitude and more heat ------ping/knock city if your engine is sensitive.
Atlanta at 1000 feet labels 91+ as 93 because it acts that way in a special temp test at 68F but in Summer heat may not test above 91. Rarer to see 93 at warm sea level cause it doesn't exist.
There really are only 2 grades of gasoline produced [fungible regular and fungible premium] with differing Reid vapor points and some emission tricks for EPA zones. Since ethanol cannot be transported by pipeline [picks up the water in lines used to divide the batches]. Splash blended in at local depot.
MTBE oxygenated gasoline could/can be transported via pipelines......so actual 4 types might be around raw reg and raw premium, then MTBE reg and MTBE premium.
Did some testing [this month] on 89 vs 93 as long as the temp was below 50F fine, Q rattled like hell at 60F on 89 [QT retailers]..........it took a can of BG44K or 2 full tanks of 93 to get back to normal after a single tank or two of 89.
Save a penny making a million gallons a day means $10,000 per day x 365 days.......some real money to the bottom line.
The blending chemist/the blending computer engineer........running on the ragged edge of knock to keep their jobs and maybe get a tiny bonus.
"Lets see this load is going to a cold high altitude place [will it be warm or cold the day it's used by the engine].....I'm going to save a $1,000 bucks and make the higher ups happy ........unfortunately who knows it might get diverted to somewhere else along the pipeline.
You really cannot trust the pump labels everywhere on every day as the hourly mix changes constantly.......and by the time it gets to filling stations it has interreacted for days......weeks plus the time in your tank.
The salvation is that different 10,000, 100,000 gallon lots get blended together in the giant holding tanks [local big city tank farms] where the pipeline water slugs get separated out.......kind of like cows milk by the gallon.........a little bit of each cow included. Hope mine wasn't sick that day........takes a lot of young kids in a swimming pool to make it unsafe for swimming.