I seem to have started backwards from all the advice I have read from various forums here on thirdgen, although it's not entirely my fault

In October, I had bought an 89 Formula from a guy that already had a ZZ4 crate engine in it (the body was real rough, so I just wanted it for the new engine and TPI setup).
Now this long block already has a pretty hot cam, aluminum heads, etc. and he had it sitting under a stock TPI setup. When I pulled the engine and drive train, I ported the intake and plenum to gasket match the parts. I swapped the whole thing out with my old 305 TBI in my (just painted) 89 Formula - harness, ECM, everything. The ecm also had a stock chip in it, and I postponed ordering a custom chip until I finished the drive train and engine.
Since I have been a member of thirdgen, I have learned a lot of stuff from some very knowledgeable people - especially about computer systems on tuned port systems. Traxion and other people have convinced me to go ahead and program my own chip, so I bought the parts I was lacking and modified a calibration chip to accept a zif.
I went and burned the arap bin into an empty EPROM and stuck it in. It works fine, and though I haven't done any kind of scientific testing, there does seem to be a sotp difference in acceleration.

I know this was a long intro, but here is the question:
I know it can do more, but I need a base starting point for this, and I am not experienced enough to know what king of spark advance, WOT % etc., I should be putting into the tables.
Would a bin from an 89 corvette, for instance be a good place to start? The vette had 58cc aluminum heads
(like my zz4), and a lot of other similarities, so it would make sense to me to use it, but I would like some confirmation before I go ahead an plug it in.
Using the compare function of Tunercat, I can see major differences between the stock 350 bin and a bin from an 89 corvette (ARAR_7165_89vette_auto.bin) in a lot of the tables, and from what I can gather these are because of the higher performance motor used in a vette.

I can't wait until the moderators get a discussion going on the 165 ecm's - I need this info!

(Trax - I think my way of installing a zif on a memcal may be a little more efficient than the method in your tech article - can I send you a separate email? I would like to compare notes )


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89 Firebird Formula
WS6 package,ZZ4 Crate engine
SLP 58MM TB, Edelbrock TES Headers
Random Tech 3" cat, SLP 3" stainless exhaust
9 bolt rear, Hotchiss swing arms, Lakewood panhard rod
Corvette 2/4 servo, kevlar band, full poly rear.
Centerline 16x8 rims, B.F Goodrich drag radials

 

Lee ... feel free to send details. I only worked with the ZIF for a couple of times until I acquired a HyperTech adapter. I prefer using those.

Tim

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TRAXION's 1990 IROC-Z
Best Time = 12.244 @ 112.51mph (1.778 60' / 7.819@88.32mph in the 1/8)
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels.
Gunning for NA 11's with bigger cam, bigger stall, and bigger exhaust.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

 

Find the oem bin that most closely matches your combo.
Start in small steps adding a LITTLE timing, fueling and take notes, and forget SOTP, get something to measure perfopramance.
Start from slow and work towards WOT. Then make a few higher TPS runs. Having a Diacom + or some form of datalogging is helpful.

 

BTW, with the AL heads you might make best power with as little as 28d WOT Timing, and they generaly like a pretty good amount of timing at cruise

 

Grumpy:
I would agree with your statement except if the EGR is disabled on his motor. The ZZ4 does not have EGR passages in the heads since the Vette used external EGR into the manifold. I recently finished programming the timing on my 383 TPI with no EGR and Edelbrock aluminum heads, 9.6:1 compression and 204/214 cam. I had to remove QUITE a bit of light cruise timing. In the end it needed more than 10 degrees less than the stock Vette spark table at 60 to 85 kPa manifold pressure and 1500-3000rpm. These comments are based on what worked for me.

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Dave Zelinka

 

Yelofvr wrote:
Grumpy:
I would agree with your statement except if the EGR is disabled on his motor. The ZZ4 does not have EGR passages in the heads since the Vette used external EGR into the manifold. I recently finished programming the timing on my 383 TPI with no EGR and Edelbrock aluminum heads, 9.6:1 compression and 204/214 cam. I had to remove QUITE a bit of light cruise timing. In the end it needed more than 10 degrees less than the stock Vette spark table at 60 to 85 kPa manifold pressure and 1500-3000rpm. These comments are based on what worked for me.

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Dave Zelinka


You see, this is my problem! I am dealing with an engine that is so far off the stock base that I am having a difficult time in finding a base starting point. Dave is right - although my EGR is physically present, it doesn't do diddly. I did burn a new chip with the 89 vet
Bin, and it ran fine, but I haven't put it on the scanner to check for knock retardation at
Different RPM's. Mostly because it hasn't stopped snowing since December...
I did find http://<a href="http://www.cis.udel....~davis/z28</a> and he has done some prom work based on pretty much the same setup I have on my car, so I think this will be a good base to start from. (He has lots of other bins there - both modified and stock). He ended up reducing his spark timing table by 10 degrees across the board, which is exactly what you advocate.


I have so much to learn…



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89 Firebird Formula
WS6 package,ZZ4 Crate engine
SLP 58MM TB, Edelbrock TES Headers
Random Tech 3" cat, SLP 3" stainless exhaust
9 bolt rear, Hotchiss swing arms, Lakewood panhard rod
Corvette 2/4 servo, kevlar band, full poly rear.
Centerline 16x8 rims, B.F Goodrich drag radials