Turbo motor

[Bruce Plecan]

|
| Under boost I have noticed that my car has a tendency to ping more at
| 3000 rpm , which I would guess is the tuned configuration of the motor.
| So boost and/or timing can be reduced. If the timing is reduced to
| prevent any detonation, and the boost is left alone. It will generate
| spectacular boost numbers and it runs strong. But it runs about the same
| when I reduce the timing a little bit and limit the boost. So it looks
| like there are two different ways to get to the same point. So what is
| the best way to tune a turbocharger motor? I would guess reducing the
| timing a little, and then limit boost to prevent detonation...

There's never a good reason to burn more fuel then what the engine needs.
All the extra carbon has to go somewhere.  If you do EGT's AFR and Plug
reading they all should point to one being better than another.

| Also I have noticed that GM spark rpm/load tables arrays seem to be 16
| bytes wide, even when its a Grand National turbo motor. It seems like
| that if its a one atmosphere map unit the table should be 32 bytes wide
| for the same resolution. Any comments on this one?

Well, they been running the Buicks since 86 with the intercooler, and making
good HP.  The syclones since 91.  I'd say that the resolution is good
enough.
Ya, might be nicer, but as far as necessary, that's your call.  To me 19
would be perfect, @ 500rpm steps.
   The big isue is running the right MAP so you don't run out of
CALIBRATION.
If ya run 14 PSI of boost run a 2bar MAP.  If you run 18 use a 3 bar MAP.
That's how I see things
Grumpy