Crazy Calibration Question

[Two Fangs]

OK, So I understand that I can use the Stoich table in HPT as a global fuel adder, which is cool. What this allows me to do is max my stoich table at 32 and cut the size of my E85 injectors by over two thirds to limit the amount of scaling I have to do to fit under the 63.5 lb/hr hard coded limit in the IFR table. By drpping the fuel pressure on my ID2000s just a tad, I do not need to scale at all to fit under the limit. So while this means I can keep all of my low end MAF resolution since I do not have to scale this thing, I am not sure that the benefits are as exciting as I would like them to be. The reason is, I am still stuck with a 1.36 g/cyl limit on the spark tables. On the 2008 E38s, the g/cyl axis is not scaleable. It would seem like I could just make sure the last row of the table will carry the thing out under crazy boost, but I wanted to get some thoughts on it. Should I just scale anyway to get the spark table increased? At 20 PSI, I am going to run out eventually anyway, without scaling the thing so crazy that I lose all of my low end resolution. I am thinking if I drop the last row a few degrees of the HO timing able, I should be able to let the bottom row carry me out, but wanted thoughts on it. That is all...

[NicD]

OK,

So I understand that I can use the Stoich table in HPT as a global fuel adder, which is cool. What this allows me to do is max my stoich table at 32 and cut the size of my E85 injectors by over two thirds to limit the amount of scaling I have to do to fit under the 63.5 lb/hr hard coded limit in the IFR table. By drpping the fuel pressure on my ID2000s just a tad, I do not need to scale at all to fit under the limit.

So while this means I can keep all of my low end MAF resolution since I do not have to scale this thing, I am not sure that the benefits are as exciting as I would like them to be.

The reason is, I am still stuck with a 1.36 g/cyl limit on the spark tables. On the 2008 E38s, the g/cyl axis is not scaleable. It would seem like I could just make sure the last row of the table will carry the thing out under crazy boost, but I wanted to get some thoughts on it. Should I just scale anyway to get the spark table increased? At 20 PSI, I am going to run out eventually anyway, without scaling the thing so crazy that I lose all of my low end resolution.

I am thinking if I drop the last row a few degrees of the HO timing able, I should be able to let the bottom row carry me out, but wanted thoughts on it.

That is all...

Yes, using the stoich table works well for getting around scaling limits or to make the math nicer so to speak but yes the spark tables don't change and you are still stuck with their limitations. At first glance this would appear to cause a problem especially with turbo cars and their pretty dynamic boost swings with not being able to have lower/higher timing commanded at the higher boost levels but I really much prefer to keep the timing lower anyways and just let boost do it's thing. This keeps heads on motors by not trying to push the timing hard at the middle boost levels since when you really want to push it you are going to be at higher boost anyways and you will more than likely be at that bottom row anywhere in the middle/high boost range.

Of course you could always make it a 3d solution by commanding different a/f ratios per boost level and using the timing/afr table and throwing that in the mix, but personally I think that's over complicating something that isn't necessary.

[Two Fangs]

Thanks, Nic I appreciate the reply.