Yet another tuning question
Road Warrior
Joined: Feb 2009
Posts: 1,274
Likes: 130
From: Now Western TN
You can actually get mileage and performance. The settings become a little trickier with a lot of mountain riding because you are into the throttle a lot going up mountain passes so the trick is to set the performance part of the tune only where you really demand it. But if your riding calls for climbing a lot of steep grades mileage is going to suck no matter what. You have to give the thing gas.
From some quick research:
"Altitude decreases an engine’s octane requirements because of the change in air pressure. The higher elevations have a lower level of air pressure, which means an engine needs less octane to properly fire due to the lower ambient pressure. In certain states, such as Colorado where the altitude is generally above 5,000 feet in the mountain regions, 85 octane gasoline is sold, while in lower elevations 87 octane is the lowest sold.
When an engine requires lower levels of octane to “fire,” the overall efficiency of the engine is also lowered, which means the engine works harder to achieve the same results. However, less fuel burns, which means the overall fuel-per-mile efficiency is increased because the engine is working at a reduced compression rate. In short, you can get higher miles-per-gallon at higher elevations, but the power of the engine is also somewhat reduced."
So what I am asking is how does all this effect the tuning at places like Denver? If he tunes for Denver but then goes to Kansas and loses 4000 ft of altitude, what happens to his gas mileage and perfromance?
Also how do you compare that to like iClick who is most likely at sea level?
How does his mileage to performance hold up in the higher elevations?
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
It's a little bit of a complicated question. The way I have always understood things is oxygen density is what matters the most. The higher elevation the less oxygen. Less oxygen, less power, so more throttle to maintain speed.
Thread Starter
|
Cruiser
Joined: Apr 2012
Posts: 165
Likes: 0
From: Denver
What tuner do you have installed now?
I have a SERT now so no real ability to view or change anything.
A head wind might explain the bad mileage at 80mph if you experienced it only once, but even then that would seem low. If the current tune takes a dive toward the rich for the KPA reading realized at 80mph this could happen. I've seen lots of tunes running closed-loop (14.4 - 14.6:1) up to 80 KPA, then 13.0:1 (open-loop) at 85 KPA, and that will make a big difference if you ride there often, as it isn't hard to move above 80 KPA in normal riding. Having a look at your AFR table would be helpful.
The PV would be a good recommendation, but be prepared to do some homework. There's a sticky thread for the PV in the tuner section of HDForums. There is the so-called AutoTune tuning method, which basically let's the PV do the datalogging and calculations with minimal user interaction, and a multi-step method of using WinPV and PVTune software (downloadable from the DJ site) for more selective tuning. I use the latter, as I like the control. There's no reason you can't tune for maximum mileage for your setup with little or no performance decrease, but if you have a mismatch somewhere (e.g., cam and pipes) you may never get it dialed in to your requirements.
What do you mean by mismatch? How would I know? I had an andrews 48H before the 57H and the head job. I was getting close to 50mpg on the interstate then. Don't ask me why I changed. Right now I'm wishing I hadn't.
FWIW, I just helped a guy with a 103 w/57H cams installed and he is only getting 25mpg, so you're doing much better than he is. He has mismatched parts and we're working on a fix now, although I'm not a hardware matchmaker, so I can only help him with the tuning.
I have a SERT now so no real ability to view or change anything.
A head wind might explain the bad mileage at 80mph if you experienced it only once, but even then that would seem low. If the current tune takes a dive toward the rich for the KPA reading realized at 80mph this could happen. I've seen lots of tunes running closed-loop (14.4 - 14.6:1) up to 80 KPA, then 13.0:1 (open-loop) at 85 KPA, and that will make a big difference if you ride there often, as it isn't hard to move above 80 KPA in normal riding. Having a look at your AFR table would be helpful.
The PV would be a good recommendation, but be prepared to do some homework. There's a sticky thread for the PV in the tuner section of HDForums. There is the so-called AutoTune tuning method, which basically let's the PV do the datalogging and calculations with minimal user interaction, and a multi-step method of using WinPV and PVTune software (downloadable from the DJ site) for more selective tuning. I use the latter, as I like the control. There's no reason you can't tune for maximum mileage for your setup with little or no performance decrease, but if you have a mismatch somewhere (e.g., cam and pipes) you may never get it dialed in to your requirements.
What do you mean by mismatch? How would I know? I had an andrews 48H before the 57H and the head job. I was getting close to 50mpg on the interstate then. Don't ask me why I changed. Right now I'm wishing I hadn't.
FWIW, I just helped a guy with a 103 w/57H cams installed and he is only getting 25mpg, so you're doing much better than he is. He has mismatched parts and we're working on a fix now, although I'm not a hardware matchmaker, so I can only help him with the tuning.
Thread Starter
|
Cruiser
Joined: Apr 2012
Posts: 165
Likes: 0
From: Denver
I've read a number of your posts in different threads. Your views are one of the reasons I may give tuning a try. I seems auto tune pro with wide band sensors would help and maybe expedite the process of getting a tune I might be happy with. Do you agree?
Thread Starter
|
Cruiser
Joined: Apr 2012
Posts: 165
Likes: 0
From: Denver
Now that you mention it. I wonder if I actually had it in gear. That would explain the good gas mileage. LOL.
Thread Starter
|
Cruiser
Joined: Apr 2012
Posts: 165
Likes: 0
From: Denver
That's not really what I am asking, I asking about air density/barometric pressure and the effect it has on the motor, not mountian riding.
From some quick research:
"Altitude decreases an engine’s octane requirements because of the change in air pressure. The higher elevations have a lower level of air pressure, which means an engine needs less octane to properly fire due to the lower ambient pressure. In certain states, such as Colorado where the altitude is generally above 5,000 feet in the mountain regions, 85 octane gasoline is sold, while in lower elevations 87 octane is the lowest sold.
When an engine requires lower levels of octane to “fire,” the overall efficiency of the engine is also lowered, which means the engine works harder to achieve the same results. However, less fuel burns, which means the overall fuel-per-mile efficiency is increased because the engine is working at a reduced compression rate. In short, you can get higher miles-per-gallon at higher elevations, but the power of the engine is also somewhat reduced."
So what I am asking is how does all this effect the tuning at places like Denver? If he tunes for Denver but then goes to Kansas and loses 4000 ft of altitude, what happens to his gas mileage and perfromance?
Also how do you compare that to like iClick who is most likely at sea level?
How does his mileage to performance hold up in the higher elevations?
From some quick research:
"Altitude decreases an engine’s octane requirements because of the change in air pressure. The higher elevations have a lower level of air pressure, which means an engine needs less octane to properly fire due to the lower ambient pressure. In certain states, such as Colorado where the altitude is generally above 5,000 feet in the mountain regions, 85 octane gasoline is sold, while in lower elevations 87 octane is the lowest sold.
When an engine requires lower levels of octane to “fire,” the overall efficiency of the engine is also lowered, which means the engine works harder to achieve the same results. However, less fuel burns, which means the overall fuel-per-mile efficiency is increased because the engine is working at a reduced compression rate. In short, you can get higher miles-per-gallon at higher elevations, but the power of the engine is also somewhat reduced."
So what I am asking is how does all this effect the tuning at places like Denver? If he tunes for Denver but then goes to Kansas and loses 4000 ft of altitude, what happens to his gas mileage and perfromance?
Also how do you compare that to like iClick who is most likely at sea level?
How does his mileage to performance hold up in the higher elevations?
Road Master
Joined: May 2008
Posts: 1,196
Likes: 14
From: connecticut
I recently built a tman 107 for a customer. He got between 47-52 mpg in touring mode on the highway70-80 mph traveling from Connecticut to key west Florida. He was consistently .5 to 1.2 gals less fuel than a stock 110. The owner always has been a fuel miser compared to my driving style.
The build can be seen here and its tuned with a tts making 131.5 hp.
https://www.hdforums.com/forum/touri...107-build.html
The build can be seen here and its tuned with a tts making 131.5 hp.
https://www.hdforums.com/forum/touri...107-build.html
Thread
Thread Starter
Forum
Replies
Last Post
dschock
Ignition/Tuner/ECM/Fuel Injection
3
Jun 11, 2014 08:22 PM