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Re: Turbo V6 Tuniing continued/Intronics Emulator update



> Excellent work, Jeff!

Thanks, over 200 hours of emulator and testing can tax your patience and
determination.  Almost took that long for the owner of this car to realize
that the car would not run perfect right off, and even after a few days of
tuning, but he learned to accept a few events of stalling and bog but I
think
it was worth it ;-).

> I'm following this thread anxiously, as I'll be doing the same w/ a Sy -
> Vortec heads, cam, 40# injectors (up from 30#) and bigger turbo.  I'm a
> newbie @ chipping, but am learning a lot and have a pretty good prog on
the
> old setup.  Waiting for all the parts to arrive so's I can reassemble the
> beast & get back on the road.

When I am finished doing this chip, I will make notes on what worked best to
accommodate large injectors and post it here, only problem is the TGP bin
approach to things is a bit different than the SyTy bin, but it all helps.

> Regarding the knock retard; *removing* it from the ECU program (or
> disconnecting KS) sounds dangerous to me (ala Kenny Bell's chip) - *but* -
> something to try, if the ECU tables will permit it:  Decay it out *real*
> fast.  One knock event will take about 2 seconds to completely decay out
> the retard, meanwhile you're through the critical RPM/boost range where it
> was needed, probably in the next gear.  If you *are* getting knock retard,
> this can be good for some very nice acceleration improvements - I cut 0.5
> secs off my 0-60 times by setting the decay to 10x normal rate.  You'll
> still have the benefit of the KS retarding when needed, but just for an
> instant, then its back to normal.  I'm looking for almost constant knock
> retard, but in the 2° range or so - then, you know you're real close to
> optimal, and can change the timing tables accordingly

For the engine in the SyTy, though I like your idea, would just say to be
even more careful than usual as these engines can die a quick death from
knocking (I know of many horror stories, cracked heads, cracked blocks,
eewww).  At the point of knock, pressure and temp values inside the
combustion chamber makes some wicked peaks so it is best to keep knock down
low and for the shortest period of time if necessary.  And true, riding the
edge of detonation means your making peak power for your setup.


> As a side note, after installing the cam & modified distributor (moved
> clamping boss), I was getting false knock retard @ 2000 RPMs of up to 18°.
> Moved the KS to the front of the engine (where the KS for the MSD unit
was)
> and its ok now.  Checked the knock indication w/ a stethoscope.  Re-hooked
> up the rear, stock KS recently (after maybe 500 miles on the new stuff),
> and false knock @ 2000 is now down to 4° or so.  I assume a thousand or so
> more miles, whatever's causing it will be worn in even more, and it may be
> gone.  Then, I'll re-hook up the original KS.  BTW, the SyTy KS has a 3.9k
> internal parallel resistor, so the ECU knows its not there; can't just
> unhook it w/o throwing a code (checks for open or short).

Nice researching and testing there Barry, glad to hear the SyTy ECM will not
accept an un-plugged knock sensor, too critical for these engines boosted.
I too have an extra knock sensor in my Typhoon, running off an MSD, and have
changed the sensor to match the stock one so the frequency is more matched
to this engine per GM (yea they have been known to be lame in their
engineering but the MSD does not offer different sensors for different
engines), and I set it to yell before the Corvette knock control system
running off the DFI shows me knock retard values.

> I'm also using an MSD 6a box w/ MSD's adjustable timing control - makes
> timing adjustments quicker & easier than doing chip changes here; can go
> +/- 8°.  Now, if there were just a way of doing the same thing w/ injector
> 'on' time........  Time for an emulator.......

>From the values you find that work on the MSD, you could program them into
the chip based on areas of spark changes that worked, nice idea.  AS FOR the
emulator from Intronics, for the TGP ECM it did not work out well
((  Everything hooked up well and ran after some playing but as soon as I
made a single value change, the service engine soon light would flicker once
and the Diacom would be kicked off line!!!  After a couple of single
changes, done slowly on the emulator the ECM decided to complain and through
in the limp home towel, oh well, $89 is not much but at least the value for
others here to keep looking was of greater value.

> BTW, don't let Grumpy find out that you're relying on stock oxy sensor for
> fuel values............}:}E

Yep, ol grumpy is always on the prowl for our best interest, keeps us all
on our toes.

> Keep it up & let us (me) know how it goes - Barry










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