My Crazy TPS/MAP Thoughts

[SVOboy]

Well. I'll just assume everyone knows how hondas new r18 works, I know you don't, but I can't make a coherent thought, so if anyone wants me to post a good link I will.

Anyway.

WOT reduces pumping losses dramatically, but unfortunately WOT = rich mixture. And especially at the low rpms which we like WOT doesn't mean any more acceleration.

But, what if we were to have a switch that could interrupt the TPS signal and give it a constant whatev. We could go wot but have the fuel stay at a 20% tps thing, so it wouldn't go rich and lug like hell. Mehbe this should be done at the MAP. Actually, yeah, it should be done at the map, but I imagine the tps as well because it'll sense the wot, but you get the idea.

I'm sorry, I'm really tired, mehbe someone clever will make this make sense...

[omgwtfbyobbq]

If we trick the ECU into thinking it's not WOT, but right before WOT where it goes into open loop/rich, then we'll be getting more air than fuel compared to our maps and run the risk of detonation. What would be cool is to rig a knock sensor to interrupt our masking of the TPS if there is knock. We could mess with the MAP signal too, with the same results. I think the limiting factor is what the output range each sensor is, so we could pick the easiest one to fool.

[SVOboy]

The thing is though, especially at low rpm, if you go wot your intake valves aren't really opening up enough to suck very much more air, so the extra fuel just kinda goes blah and you have crap acceleration (at least this is what I notice with my car). So I figure, at least at a certain point, the fact that your rpms are so low means you're not really going to increase airflow enough, but you can eliminate that huge blah of throttle plate friction.

[omgwtfbyobbq]

Hmmm... is there that much extra fuel at low rpm during WOT? I mean, I doubt manufacturers are having the injectors dump any more than the mapped amount of air/fuel, in other words, the throttle plate shouldn't matter much, if at all, but don't take my word for it, I've had some *** ideas. A wideband O2 sensor would show you how rich you're running... And I bet that's just what any one of us needs, more crap to spend money on!

edit- I see, the r18 ECU can delay the intake valve closing to get more air and reduce pumping losses. Yeah, changing the throttle plate/or MAP signal may do the same thing, except you'll essentially be running lean, an since your ECU doesn't know how to deal with it, if you get knock or run too lean, it may throw a code, pull timing, and possibly switch to open loop. If you really want to lean your engine out, I'd go with a stand alone ECU that allows for knock sensor input.

[SVOboy]

Well, lemme take a screen shot in a second. A WBO2 would be nice, but I'm too lazy to spend 150 on the controller and all that ****.

[SVOboy]

The last columns are junk but that's my ecu fuel map right there,

[omgwtfbyobbq]

Well then, mess with the signal and run it lean to see what happens. Hopefully you can find a spot where the ECU tolerates your lean running condition...

Edit- Is that pressure and injector pulse duration?

[SVOboy]

Indeed, I believe that's what it is. Anyway, the ecu will tolerate any lean condition I tell it to, mwahhaa. So yeah, I'll think about it.