Spark Tuning

[Programmer]

PMFJI--disconnecting the TV cable sets the transmission internal pressures
at maximum. This is "default" in case of a broken cable  and the possibility
of lunching a
transmission.

Lyndon IPTECH
-----Original Message-----
From: Marc Piccioni <mpiccioni at attcanada.net>
To: 'gmecm at efi332.eng.ohio-state.edu' <gmecm at efi332.eng.ohio-state.edu>
Date: August 7, 1999 7:35 PM
Subject: RE: Spark Tuning


>Careful, the 4L60 uses the kickdown cable to alter the line pressure in the
>transmission -> WOT generates high line pressure to ensure proper shifting
>and clutch pressures. Disconnecting it may result in a toasted
>transmission.
>
>/Marc
>
>----------
>From: Dave Zug[SMTP:dzug at delanet.com]
>Sent: August 4, 1999 3:42 AM
>To: gmecm at efi332.eng.ohio-state.edu
>Subject: Re: Spark Tuning
>
>Hi Mark thanks for the info ant time...
>
>The car has ALUM heads.. admittedly the intake runners in the heads
>are far too large for the stock TPI setup and I've lost some of my
>monster torque I used to have. (200cc intake riunners on the heads,
>2.02 intake, 1.60 exh) the car is an automatic w. 2.73 or 2.77 or
>whatever  (the really bad gears). the factory correct cal is AUJL.
>the differences are mainly the TCC stuff. I thought the supercharger
>would make up for the TPI setup a bit and give me a decent setup but
>it looks like I'll be going for more boost and an intercooler and
>intake runners  and probably headers to compensate.
>
>Now 4th gear at 600 rpm.. in an automatic may be tough, I wonder if
>I can unhook the TV cable and lock the tcc manually or something to
>get close.
>
>with the stock vette cal ARAP I get 1 knock count every 1-2 shift so
>I see I have a ways to go before the engine is unhappy.  what
>generally can I expect from the alum verses iron heads in the
>way of advance toleration for a given octane?
>
>
>> From:          "Mark Romans" <romans at pacbell.net>
>> To:            <gmecm at efi332.eng.ohio-state.edu>
>> Subject:       Re: Spark Tuning
>> Date:          Sat, 31 Jul 1999 15:00:06 -0700
>> Reply-to:      gmecm at efi332.eng.ohio-state.edu
>
>> Hi Dave:   I have a friend that has an 89 TPI engine is his 79 Camaro, he
>> also has installed a 95 6spd and a Vortech.  He has recently been having
>> ignition problems.  I have done a series of chips for him to address a
>> number of driveability problems.  He called me and just pulled off the
>MSD
>> boost timing controller.  His ign problems are gone and he can't believe
>how
>> well the car is running.  He has run it with diacom and recorded some
>runs
>> and says detonation is minimal,  ie: the ecm is pulling some timing out,
>but
>> not much and not near what the max is.  I have it set to pull out as much
>as
>> 15 degrees and it is not pulling out more the 6-8.  The weather has been
>a
>> bit cooler than normal for Northern CA so it may still detonate a bit
>more
>> if it gets over 100 out, so we'll have to wait and see.
>>
>> The way we tuned the car was to make sure it had plenty of fuel,  02
>above
>> 900 mv and load the engine in 4th down to about 600 rpm and go to wot and
>> record the run to redline with the diacom.  This puts the engine under
>max
>> load.  If the ecm is not pulling out more than a few degrees of timing,
>> perfect.  I have tried for zero knock retard and the car slows down.
> Also
>> in lower gears since the rpm's climb faster the engine likes a few more
>> degrees of timing.
>>
>> Are you running aluminum or iron heads?  Is this an automatic or manual
>> trans?
>>
>> Mark
>> -----Original Message-----
>> From: Dave Zug <dzug at delanet.com>
>> To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
>> Date: Friday, July 30, 1999 12:40 PM
>> Subject: Spark Tuning
>>
>>
>> Don't think I've seen this subject and thought I'd get a head start
>> on it...
>>
>> Background:  1989 5.7l TPI, 165 ECM, ARAP (vette 350) BIN,
>> Supercharger, alum 200cc intake runner heads, stock compression,
>> 13.50 quarter mile on 5 psi boost w/ stock chip.
>>
>> What I plan on doing is subtracting 8 or 9 degrees from the stock
>> main spark table.. going for a few runs, checking the data... then
>> bumping all the load / rpm values that did NOT knock up a degree, and
>> all the ones that DID knock down a degree (lower --> toward 0 btdc).
>>
>> Now WOT spark advance I see is available to me as well. that's not
>> what I'm doing right now. and I know I gotta get the fueling right
>> to be able to start the sparking stuff, correct?
>>
>> If I can get a large range represented in the 1 run of recorded data,
>> then I may be able to feed it into a (this is getting old I know)
>> utility that will spit out a new table (just looks at rpm, lv8, knock
>> and decides +1 , 0 , or -1, pretty easy)
>>
>> I've thrown out my guess on procedure here.. if anyone has the "real"
>> way please educate us! thanks.
>> ~~~
>> Dave Z. www.delanet.com/~tgp
>>
>>
>>
>>
>~~~
>Dave Z. www.delanet.com/~tgp
>
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