Start – 1 – 2 – 3 – 4 – 5 – 6 – 7 – 8 – 9 – 10 – 11 – 12 – 13
In which I refine the EFI Tuning, lose interest, and sell it.
Lucky 13. The bonus page of goodness!
8063 $4D Tuning that worked (subject to change):
Holley Big-Bore TBI unit, GM pod with 61lb Injectors
Fuel Pressure = 18psi, vacuum-referenced-fuel-pressure-regulator (provides 12psi at low MAP – you need this).
61lb injectors at 13psi (stock) can feed about 245hp. This engine should make about 320hp. If you raise the fuel pressure, the injector “acts” bigger – you need to tell the computer that it now has a bigger injector
Deceleration Fuel Cut Off can do weird things to tuning. Best to turn it off.
Deceleration Enleanment can do weird things to tuning. I reduced the top two settings as there was some odd throttle-response issues going on. Might be an idea to disable it.
This just didn’t make sense. Did the ECU actually expect to be totally lean (like 0V)?
Magic happened here. I -think- reducing the O2 Proportional Gains makes the computer react LESS when the O2 fluctuates. The O2 says lean, but the ECU would always pull fuel, and I was getting lean surge. I reduced this a lot.
Not by any means completely refined, but working well so far.
It -seems- to drive really well so far.
(Addendum – I took out a LOT more O2 Prop Gain across the board, as well as INT Delay O2 Error Multiplier. This “calmed” the O2 reaction down and smoothed the driveability significantly)
Added an engine oil cooler to knock down engine temps.
(Addendum: Oil cooler removed, because I felt it was taking away oil pressure, and it took way too long to heat up in the fall.)
Finished building the battery-disconnect knob, as per drag rules. Still need to label “OFF” once the paint has cured a bit more (Tremclad “Hammered” finish, one of my favourites, right up there with “Bed Liner”).
And started replacing the interior paneling for a more finished look. The rear plastics are almost impossible to find, so I took my time trimming them.
Way back I bought a Tach Adapter off eBay that was programmed to take the 8 pulses of the V8 and turn it into 3 pulses for the stock tach. It was sort of successful, but not something you would rely on. It kinda fidgeted and floated around. I contacted them, and they said to put a 100K resistor inline with the input as that would affect the Time Constant of the circuit and smooth it out. Now, I’m not an electrical engineer, but I figured the tach adapter wasn’t getting a significant signal, and adding a resistor inline would just make it less significant a signal. And it did. The tach was lazier and worse.
So, because I didn’t want to have to troubleshoot this, I decided to put the Firebird factory tach guts in the Firefly cluster. Something I should have done back then. It was actually easier than I feared.
First, pull the tachs out:
Here are the tach guts side by side. Firebird on left, Firefly on right:
Backside, Firebird on left, Firefly on right. No, I didn’t notice any similarities yet:
I sanded down the perimeter of the Firebird tach face (I smoothed it up more later), and drilled two holes so it could line up with the existing holes in the Firefly face. The sweep is different, and the scale is different between the two, so I can’t just plunk the ‘Bird guts and use the Firefly face:
Then I noticed they were very similar. The Firebird cluster is made by Denso. The guts are super super similar. I bet if I just changed these mounting pins…..
By unsoldering them….
And attaching the Firefly pins to the Firebird tach guts….
It will all fit inside the cluster, and use the existing wiring and everything:
And it did!
Apparently the car made it to BangShift.com! I am honoured!!
Started finishing off the interior panels. I need to make this car more “presentable.”
First, make a pattern out of cardboard.
Then I transferred the pattern onto 1/8″ hardboard, but it turned out I didn’t have the right panel clips, so instead I made the panel out of 1/16″ ABS.
Then wrapped in gray marine vinyl I picked up at Fabricland, but gluing this down with 3M 77 adhesive was a gooey mess, so I don’t have pictures. I didn’t like how my panel clips fit under the vinyl, so instead I just poked a hole and ran them through. You will get over it. Could paint the clips gray if I care enough.
I’m half-way through the passenger side panel pattern right now.
Old and Busted:
New Hotness:
Trial fit driver’s side, because I apparently can’t measure, and need to buy more vinyl:
Trimmed the speaker covers to finish the cage:
Finally built a proper battery box, vented to the underside of the car.
Over this past winter, I started psyching myself up with enthusiasm for driving the car again. And winter just kept coming, and coming, and coming….
Finally it got warm enough and spring arrived, so I put plates on it to remind myself why I’m not in love with it any more.
The first drive to my work was full of “oh yes, this thing is a riot!” and on the way back I was “yeah, ok, I’m done with it.” I want to start the ’61 Apache.
Oh, and the battery died at work. Jumped it off the alternator bolt (it’s easy to get to) to get home, and went and bought a new battery, as a result of this:
The one remaining “carbon” header gasket I didn’t replace got replaced. I -do- like Remflex.
I’ve decided.
I submitted the Firefly to www.bringatrailer.com to be sold. It should go live within two weeks. I will post the auction here when it happens.
- I’m excited – Selling it means I can start the ’61 Apache
- I’m scared – BaT will list it only as a “no reserve” auction; I don’t want to just give it away.
As such, I’ve got a bit of a push to finish a few details.
In cleaning the car for pictures, I noticed the passenger floor was wet with coolant – the heater core repair I did previously did not hold, so I bought a new heater core. Which is not exactly the same shape, so I had to make changes to the mounting of the heater core. It’s much simpler now, and hopefully just as rigid.
I also made a simple fill panel to cover the radio and heater void spaces.
I also finished the bottom of the window net mounts. The net is ten years old, and disintegrating as I handle it.
The Fiendish Firefly listed on Bring-A-Trailer
Picture requests:
The Firefly was hauled to the new owner. It was fun, but now it’s over. May the new owner carry the torch to new heights, after a big, long, hazer.
New owners sent this, probably their first strip adventure in the car:
And I also produced this:
And to whomever owns the car now:
“Moates” closed as of 2022. BoostedNW.com is now carrying the torch of OBD chip burning etc.
And, just in case you need it: The Last V8 Firefly tuning files.
But truthfully, I would ditch the whole EFI and throw a 4-barrel and HEI on there and be done. You’d make more power with less hassle. Keeping the EFI was what helped keep this car on a low budget for me, plus, I liked the challenge, but it isn’t the best setup. (-GW 2023)