Edumakate me on t3h 7730/7727/9396 and $8f

[Blue Shift]

I figured I'd start a new thread here as an offshoot of the Holset VGT turbo project thread. For those of you who don't know, I have a Holset he351ve variable nozzle turbo that I'm eventually going to install on my 3.4L DOHC V6. All 51 lbs of it. It has a durable sliding nozzle type hotside, and has an HX-40ish compressor side, which my wheel size comparisons and turbo map plotting shows to be in the right ballpark for what I'm trying to do (no HE351ve map exists that I know of), and would be even better if I could run more than 10 lbs. Anyways, forget about that part, as I can handle the mechanical and fabrication part easy enough.

What I really need to know is more about this $8f code, since I have all of about 3 days of reading total knowledge on the subject of ECM tuning. I've heard of $59 too, but assume that since it's SBC/4.3 based with a dizzy, it'd be a less than optimal starting point.

I currently have the 9396 ECM, which if I read correctly is almost exactly the same as the 7727 plus some extra ram, which the 7727 is just a weathertight version of the '30 (which uses non weathertight case and different harness plugs). I would therefore expect to be able to run $8f on my existing ECM, possibly with some wiring harness repinning and tweaking? If this is not correct, stop me before I get too far here.

I've found a TGP bin that was patched for 5 speed use, so @$$uming it was a decent job, I would start there. My idea is to change out my current 3.4 DOHC manual PROM and set it up to run the N/A side on $8f until I actually get the turbo installed. I @$$ume I will need the following:

- Wideband kit, such as the Innovative LM-1
- PROM emulator, (Moates Ostritch 2)
- Datalogging cable for my laptop

- Or something like Moates APU1 Autoprom, which claims to emulate, datalog, and even burn PROMS. Still need WBO2.

[The Dark Side of Will]

What I really need to know is more about this $8f code, since I have all of about 3 days of reading total knowledge on the subject of ECM tuning. I've heard of $59 too, but assume that since it's SBC/4.3 based with a dizzy, it'd be a less than optimal starting point.

$59 also doesn't have very good idle algorithms and is generally pretty tough to tune, from what I hear.
I think Sinister ran $8F in a 9396 for somebody.

[FerrariFan]

I'm not a regular poster here but thought I'd jump in since I may be able to offer some insight. I'm running $8f on a 7727 ecm now. I've got a 3.4 dohc with a intercooled Garrett GT32-76r turbo and 42lb injectors. Runs pretty good so far on 10lbs boost. I've been working on fine tuning it lately with a member from the TGP forum. It has a tendency to stall when coasting to a stop sometimes (5spd) and is hard to start when it's warm. the GM pcm is definately a cheaper alternative to the aftermarket PCMs.
$DF is probably better for NA, I had mine running DF with no problems at all before the turbo. $8f will require a 2bar map sensor.
You'll need a Moates PROM adaptor to plug your emulator into. I'm using Tunerpro with a Moates Ostrich emulator, and an Innovate LC-1 wideband.

Right now I'm trying to figure out how to get the PCM to recognize the Fiero VSS. It indicates 1 mph when I'm doing 60 mph. There is a road speed constant and an IP divisor value in the code but so far changing them doesn't do much. I've checked that I've got continuity from the VSS to the PCM and it checks out. My speedo works fine since it's a programmable vdo and can accept any ppm input.