Modified IDM and tuning

[907DAVE]

Originally Posted by cleatus12r

As far as the whole fuel/"timing" thing goes, you can forget some of the stuff you've learned about a gasser. Too much fuel down low will "snuff out" the turbocharger and you will not get fast spool-up. The same goes with the start of injection; by advancing the "timing", more heat is retained in the cylinder which can slightly delay spool-up. It's good for fuel efficiency and performance once the turbo "lights", but given two identical calibrations but running one with a global offset of a few degrees of retard (from calculated total advance) usually results in faster spool-up due to more exhaust heat being introduced to the turbine inlet.

I did not realize how big of a difference SOI makes until a few minutes ago.

I have been trying to resolve a engine "ping" that just started to develop recently, which for now I am going to blame on our new winter blend of fuel they started selling us.

After many failed attempts to get this noise figured out I switched back to an older tune that I have not ran in many months. The current program had a very aggressive ICP map which resolved most of my smoke issue, but until now I did not realize how much it hurt turbo spool time.

At about the same acceleration rate (cant base this off APP because it is too different) the boost was over 10psi more than it was before. However there was a very slight haze and EGT's were a tad higher.

Interestingly, the power felt about the same even with 10psi more boost.

There is defianatly a trade off/ balancing act to SOI.