target a/f ratio in vac
i know the a/f in boost should be about 11.5:1 but that about in vac does it have to be as rich????
|
Re: target a/f ratio in vac
14.7 in vaccum. 11.5:1 is a safe but you can go leaner.
|
Re: target a/f ratio in vac
its my built h22 im shure it could take sum leaning out maybe 12:1 in boost???
|
Re: target a/f ratio in vac
Yep.
|
Re: target a/f ratio in vac
Although CSaddict is correct in saying you can tune leaner in boost, YOU should not since you don't seem to know much about tuning. Running a richer AFR accomplishes two things. First being it slows the flame front down. Running a 11.5:1 at 20* of timing is similiar to running 12.0:1 AFR at 19* of timing. The other benefit of running richer is the fact that fuel helps cool combustion temps down a bit. In the end, running in the 11's is more than fine. If you are a tuning novice, its better to run richer than to run leaner.
As far as vaccum is concerned. The first 5 columns can be high 14's low 15's. The next 3 columns should be mid/low 14's. The next column should be low 13's. Next column should be mid to low 12's. The rest of the boost portion of the map should be in the 11's. I'm going by columns assuming you are running a normal Honda ECU editing software and you aren't retarded and changed around all the vac headers. |
Re: target a/f ratio in vac
thanks for the info guys
i got a mild tune on the car now that is low to mid 11's in boost with the timeing retarded .9 per psi witch i know is overkill but its jest street tuned for now im running 13psi on a turbonetics 62-1 i wanna fine tune it when i get on the dyno |
Re: target a/f ratio in vac
15.2-15.7 in vacuum :)
JD, please explain to the noobs! |
Re: target a/f ratio in vac
yeah please explain.........eh.....to the noobs...........out there.
not to me of course ;) |
Re: target a/f ratio in vac
There is nothing more to say. Flame speed is fastests between 12-13AFR. Anything richer or leaner makes the flame speed down. This means when you run leaner, you need to advance your timing. So you are advancing your timing and removing fuel. This could be potentially dangerous as this could potentially cause detonation. You have to understand the low will be low, but that doesn't mean detonation won't occur. It just means when it occurs, it will be far less severe. So instead of just having your pistons blown to pieces, they will die a slow death and when you go abuse your car for a bit, they will finally fail, even though the tune was fine under the heavier load conditions. In the end, you really have to understand what some are able to do is not what others are able to do. When your knowledge/experience level is low, you can't just tune for 17's AFR and expect everything to be fine. The answer is exactly what I said above. You may be able to go a touch leaner in the 4-6th columns(meaning 14.7:1-15.3:1) but again, is 1-2mpg worth the possiblity of fatiguing your pistons to the point of possible failure?
|
Re: target a/f ratio in vac
53 mpg from a D15B7 that put 121 to the wheels.......
Get a vacuum gauge and watch it during normal driving....... My current map has 41 degrees at 3000 rpm and 11", 49 degrees at 18" with the dizzy at a base of 16 BTDC, but mind is cranked to 22-23 BTDC, normal cruising = 52 degrees total timing. No loss in power, no pinging, just I understand lean burn, like Honda used on the VX setup. |
Re: target a/f ratio in vac
Agreed, I ran my turbo y7 at 16:1 for cruise and got 40 mpg. 8:1 compression didn't hurt.
|
Re: target a/f ratio in vac
I get 42 mpg running closed loop on my Z6/Y5 setup 8)
|
Re: target a/f ratio in vac
Originally Posted by Inquisition
There is nothing more to say. Flame speed is fastests between 12-13AFR. Anything richer or leaner makes the flame speed down. This means when you run leaner, you need to advance your timing. So you are advancing your timing and removing fuel. This could be potentially dangerous as this could potentially cause detonation. You have to understand the low will be low, but that doesn't mean detonation won't occur. It just means when it occurs, it will be far less severe. So instead of just having your pistons blown to pieces, they will die a slow death and when you go abuse your car for a bit, they will finally fail, even though the tune was fine under the heavier load conditions. In the end, you really have to understand what some are able to do is not what others are able to do. When your knowledge/experience level is low, you can't just tune for 17's AFR and expect everything to be fine. The answer is exactly what I said above. You may be able to go a touch leaner in the 4-6th columns(meaning 14.7:1-15.3:1) but again, is 1-2mpg worth the possiblity of fatiguing your pistons to the point of possible failure?
Tell you what man go ahead and tune your map to between 12-13 all the way accross the board but don't tell someone else to do it. |
Re: target a/f ratio in vac
Originally Posted by snm95ls
Good god man. Have you ever monitered a stock map? If it is so detrimental to the engine to run lean in LOW load conditions then why have the OEMs been doing it for 20 years? You do realize that stock programs do allow for a small amount of detonation at sustained under cruise conditions. Hell even GM, who was pretty much on the forefront of EFI innovation for a long time, ran the craptasm TBI setups into the 17:1 range. That's it, they engineered the damn things to fail due to piston fatigue.
Tell you what man go ahead and tune your map to between 12-13 all the way accross the board but don't tell someone else to do it. PS: Within the last 20 years not too many cars have been lean burning cars. I'd say its fair to say that 90ish% of cars target stoich in cruising conditions due to emmissions. Lean burning cars were anomaly. PPS: The 12-13AFR was referenced simply because people should know that is when the flame moves the fastest. Some people would think that when they lean out their AFRs they should retard their timing because thats what they do under WOT conditions. I was simply illustrating that as flame speed slows down, you need to start the process of combustion earlier to allow the peak cylinder pressure to occur at the optimal point. |
Re: target a/f ratio in vac
You have some good points I will agree.
My reading comprehension doesn't suck. I don't like people that come off as prickish know it alls. Starting your post by saying, "There is nothing more to say." makes you sound like an ass. Your previous post was much more useful. I you don't wnat people to misunderstand information then maybe you should work on your composition skills. Have a good day sir. :-\ |
Re: target a/f ratio in vac
Originally Posted by snm95ls
You have some good points I will agree.
My reading comprehension doesn't suck. I don't like people that come off as prickish know it alls. Starting your post by saying, "There is nothing more to say." makes you sound like an ass. Your previous post was much more useful. I you don't wnat people to misunderstand information then maybe you should work on your composition skills. Have a good day sir. :-\ its the way you read it. and plus, why do you give a ----, this the damn internet. |
Re: target a/f ratio in vac
he gives a damn because that's what caring people do, they don't want to see an idiot hurt themselve or their pockets.
There are some good guys left around here, and not everyone is out to screw the next guy. although it is the internet we should still look out for each other, whether it's good information being passed around or helping somebody who is broken down on a deserted stretch of highway(not w/out my 45 cocked and locked). |
Re: target a/f ratio in vac
I'm one of the caring guys, very passionate about trannys and gas mileage.
Blundell has taken my tune and use it to tweak a few cars when he was bored. On a loaded dyno at that, lean it out till power drops, then and timing. The thing is once below 10" of vaccum, timing is back to stock, fuel is trimmed about 5% over stock. |
Re: target a/f ratio in vac
Originally Posted by Mista Bone
I'm one of the caring guys, very passionate about trannys and gas mileage.
Blundell has taken my tune and use it to tweak a few cars when he was bored. On a loaded dyno at that, lean it out till power drops, then and timing. The thing is once below 10" of vaccum, timing is back to stock, fuel is trimmed about 5% over stock. |
Re: target a/f ratio in vac
2 Attachment(s)
|
All times are GMT -5. The time now is 01:28 AM. |
© 2024 MH Sub I, LLC dba Internet Brands