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.