J-series Acura/Honda

[Fred]

No pressure, but GET IT DONE YESTERDAY! How was that? :-) I really don't mind. The main thing is for your engine to have a decent rough tune on it, and a datalog proving it. Then I'll be totally relaxed about what you're doing. Until then I'm just a little anxious with occasional flash backs of that log that you posted above at night, like nightmares. ;-)

I don't understand your hall sensor comment, at all.

Re the BIP373, it's just a triple darlington suited for ignition use, they're OK, but not great. There are other devices from ON semi and ST that are better choices, and much more widely available. The BIP373 is just available from the MS crowd, and I dunno about you, but that bothers me. Search octopart for ignition igbt and see if you can find something in a to220 with 10+ amps and 400+ volts and a price/availability combo that doesn't make you cry.

[Peter]

The hall sensor looks kind of like:

Code: Select all

 
       tooth     tooth  missing tooth   tooth
       ____      ____                   ____          5V
      |    |    |    |                 |    |
      |    |    |    |                 |    |
  ____|    |____|    |_________________|    |___      0V

And the max chip looks like:

So do I need to invert the hall sensors output?

I'm going to try and keep from getting distracted, and get some tuning done today. This is kind of what I feel is going to be going on in the VE table. After drawing it I realized the map axis needs to be moved up a little to match my chart, but in general I feel like it's not too bad.

I'm thinking that the idle area should be a little rich so that it'll run well off idle. The Deceleration area should make it run lean to save fuel since I'll mainly use that area for an engine brake. I'm thinking the cruise area should give me an AFR of about 15.4:1. Then have the acceleration area around 14.7, and the WOT around 13.6. I'm planning on using a smooth curve over the rarely used areas.

[Dan]

be careful with AFR's that close to the lean side of things. Make sure your fuel is good quality if running AFR's that tight.

[Peter]

be careful with AFR's that close to the lean side of things. Make sure your fuel is good quality if running AFR's that tight.

Ya, a lot of places only sell fuel with 10% ethanol in it. I would like a switch on the dash that would let me inform the computer of the my estimation of the ethanol content in the fuel. Some day maybe. Mostly I just enjoy giving Fred nightmares.

[Dan]

Flex Fuel sensor perhaps? future code might support it or you could hack your own in?

[Fred]

+1 to Dan's first post. I have a lot more comments, but do NOT aim for 13.6 in boost, even if it's light boost, that's very marginal without water injection or similar.

Aim for stoich idle, and then richen it up if it's too shitty to drive without accel enrich, and whinge about me adding it that code.

Be careful cruising at 80+kpa with below stoich mixtures, you could easily get very high EGTs and detonation in that area. Adding boost doesn't make the 100kpa sites less loaded than they were before you added boost, if you catch my drift.

I'd probably be aiming for 11:1 or 12:1 in boost and then lean it down from there later. The default lambda table that comes with the code is suitable for a default for almost any engine. Don't even think about that shit right now, jut get your VE ironed out more and tweak the lambda table IF it's not working right for you.

If you have time to skype soon, let me know, at this point I WANT to have a chat to you about tuning. I'm no expert, but I feel I can add some value.

10% ethanol fuels have fuck all effect on anything, don't worry about that, it's the norm world wide. If you fill it with e85, expect it to run like shit. And :-p re nightmares. Read above advice and let's talk soon.

Fred.

[Fred]

Also, you're doing this fuel tuning with OEM advanced-as-fuck ignition timing! IE, you should be even richer than normal to compensate for that. Just FYI.

[Dan]

+1 to what fred said!

[Peter]

I've got a couple k-type thermocouples sitting around. If you are right, being able to see that I'm knocking on the door or 1200F (~650C) would get me to mind my manners. What do we need to do to get them setup?

[Dan]

I've got a couple k-type thermocouples sitting around. If you are right, being able to see that I'm knocking on the door or 1200F (~650C) would get me to mind my manners. What do we need to do to get them setup?

see here viewtopic.php?f=9&t=1621

would require some code support from Fred though, and he is a busy man at present!