Thread: Tuning Saga: A Love Story About a Man and His Daughterboard

Maybe the 148,000 miles and 17 years is catching up with me. In my other B13, on the same dyno, I got about 127 WHP with a similar set up, except I was running a HS header. So we shall see what the new header does for me.

In any case, the car feels great on the road. It pulls hard and spins the wheels all the way through first gear.

Thanks again for your input, Bowlcut. Once I install the header, I will check again to see whether the engine runs stronger with an AFR of about 12.5 at WOT. If that's the case, do you see any issues with running it there as a daily driver? Most engines seem to like low 13s, but the OEM tune is more in the mid-twelves at higher RPMs.

It would be interesting to work on the partial throttle portions of the map. I'm really tempted to go ahead and order a RT from Calum. I don't mind spending more time tuning on the road, but for the dyno, the RT would be wonderful.

I will eventually report back with more results. It just takes me a while to get this stuff done.

Bill

Good point, but my engine has a lot of sludge in it too...

I think it probably is the header though.... worse flowing then stock

That isnt a low number for a dynodynamics dyno run and the mod's he has. Looks very very similar to all the bolt on sr20's we have dyno'd on a DD around here in the south. Plus high numbers isnt what you are looking for. When you dyno you are looking for repeatability. Numbers are only good for internet racing IMHO.... But his numbers look spot on for his mods and a/f's. on a dynojet those numbers are upwards of 130hp or more...and for a limited bolt on older motor thats about right. Funny thing was that Carlos had a motor, think it still runs not sure, that had like dang near 300k on it, that always dyno'd 5hp more than everyone with similar mods.... we always thought it was all the extra carbon on the pistons making it a high compression motor...

Only thing id like to see bill is if you gain/loose when you bump up a point to 13.3/13.6 on the a/f's. Remember we were tuning a race car, so we wanted very safe numbers everywhere. I dont know if 12's will blow your motor or not...but if you can get to 13's without sacrificing any power and keep the mpg right, if it were my car id feel a tad better. Im not a know it all on how to make the power...just know how to make the changes in the ecu.

We usually found more power in the timing table than the fuel table. You get your a/f set where you want it, then start messing with timing. and adjust accordingly.

Yea RT makes it sooooo much nicer. Put the basic on another car and use the RT as your tuning device or the such.

Ahh, well I guess in that case I see

Thanks for the info

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Thats a really good link at Wikipedia. So winter fuel is lowering the A/F ratio to about 14:1 so Ethanol must be doing way lower then...

deleted

Yes sir I agree, will be quoting your post there too

14.7 is the AFR goal only for the closed-loop portions of the fuel map. These are the idle to light-throttle, (relatively) low RPM, conditions associated with the areas of the map that I listed above under closed-loop tuning. A factory ECU uses the narrow band O2 sensor placed in the exhaust to keep the AFR near 14.7 in these parts of the map by adjusting fuel delivery based on whether the sensor is reading lean or rich.

But the heavier load and WOT areas (the far right columns of the fuel map) are the areas in operation during WOT dyno testing. In these areas, most SR20DEs get best power output at AFRs of 13.0 to 13.3. I got a few more WHP at 12.5. So, I will probably run at 12.5 in these areas of the map if this continues to be true with further testing.

Thanks for the Wikipedia reference. Glad you found the other posts interesting.

Bill