[uhcoug2011]

Originally Posted by shiv@vishnu

There are two factors which dictate subjective smoothness of a tune car:

1) The throttle angle at which boost is enhanced. The earlier, the more torquey the engine will feel. Too early and you get a "whiz-bang" effect in the first half of throttle travel followed by a slightly less responsive 2nd half of travel. Might be pleasant in stop and go traffic but not very progressive when driving hard. Especially with 350+whp.

2) The rate at which boost is enhanced with respect to time (once the DME establishes the target). Too quick and you can get a nice punchy effect at the expense of smoothness. Too slow and you sacrifice response in lower gears and induce an annoying "rubber band" effect with respect to throttle application and torque delivery.

That said, smoothness has NOTHING TO DO with type of tune (piggyback, flash, etc,.) It is completely dependent on mapping and (with the case of pigggybacks) the quality and quantity of input variables. PROcede v1 and v2 dictated points 1 and 2 by looking only at boost pressure. v3 added a TPS input and we all saw now much things improved. v3 Rev.2 (canbus) now adds 4 more variables for load determination. The effects are subtle but there if anyone wants to do a comparison between Rev.1 and Rev.2 when running the same map.

Ultimately, throttle response is largely subjective. Some like it enhanced in addition to the extra power. Some like to slow it down with the extra power. For that reason, we make it user adjustable with the PROcede (scale of 1-5).

Cheers
shiv

+1 Excellent Response