frenchyd PowerDork
12/20/19 6:34 a.m.

Curtis said:
TheV8Kid said:
No need to get another ECU. All of the truck ECUs are equipped to read a flex fuel sensor. The tricky part is getting the right tune into it that has the ability to read a flex fuel sensor. It is a software issue. Not a hardware issue.

All of our LS cars use a flex fuel sensor. It's great. Fill it with whatever blend comes out of the pump and go. There are tables in the ECU that will add timing and fuel and handle the rest for you.

All of them? Even if it was pre-flex-fuel? As I recall (have to check the vin again... it's been a while since I bought it) this was a pretty early LQ9.

And I will need a different ECM, only for the IAC driver that I'm lacking, but it's good to know that flex fuel is built in. Very curious about your tune. You can send it to me, but at this point I haven't gone down the rabbit hole of EFI tuning. I haven't even found the rabbit or the hole. My idea of building an EFI engine is to do the hardware: injector impedance, flow, pressure, fuel line sizing, cam selection, blah blah... then give it all to a dyno-tuner-geek-computer-rainman and guide him through some of what I want.

I'm a theater tech director, so as a metaphor.... I build the physical set so that actors can perform their art. I work with lighting designers, sound designers, and set painters, so that I can say "in this scene, I want [insert character] to look sullen and guilty, so make the lights look like that." It is someone else's job to know what colors will portray that, program three universes of DMX-512, decode the protocol of light fixtures from 7 different manufacturers and 4 different decades. It is the painter's job to provide paint colors and translucency to complement it, and a sound engineer to bandpass their microphone to convey an emotion. I engineer the physical stuff... the computer geeky stuff is somewhat foreign to me. But dagnabbit, I wanna learn.

I'm very interested in hearing more. I'm totally old-school and this is my first EFI build. Ever. Other than rebuilding a 350 TPI to stock specs for someone. My idea of tuning a fuel curve is drilling and tapping for an adjustable primary step-up in the air horn of a Qjet. Not kidding. The last ignition curve I tuned was spot-welding the advance plate in an HEI to limit mechanical advance.

Let's talk.

I'm eagerly following this for my V12's my experience with computers isn't as complete as many who post here and make it sound so easy.

I've more than a few times thought to go retro. Switch the system to mechanical which is extremely easy for me to both understand and do.

The problem is Jaguar's are almost all analog, tuning consists of unsoldering a resister and soldering in a different resister. Not key strokes.
The next easy approach seems to replace all the sensors with Chevy sensors. ( injectors etc ) then plug in a Megasquirt and teach it to speak British. Or something.

alfadriver MegaDork
12/20/19 7:26 a.m.

Curtis said:
alfadriver said:
In reply to TheV8Kid :

Curtis- you may just want to keep the whole thing as is.

Well, if activating flex fuel is as easy as a mouse click and a sensor on the fuel rail, why would I? Or am I missing something?

Can you be a lot more specific where you got this powertrain? And any parts codes on the module? Can look those up on HP tuners as Calvin is suggesting and go from there. Then you will have to go back and get the pedal for the throttle input. :)

Lets hope the easy button is there!

TheV8Kid Dork
12/20/19 9:14 a.m.

Here is my tune. Have at it.

https://drive.google.com/file/d/1Q1ZjKrSJjCrs9A0O1rRvsmXB3cyj_k2U/view?usp=sharing

You will obviously have to adjust the parameters to make suit your engine to make it work, but the tune is from a 2002 Silverado. I would recommend you find a tune on the Tune Repository for an engine similar to yours, and copy everything over to mine except for the flex fue stuff. As long as the ECU is not 98 Camaro, or a 97 Corvette, and not a P59, you're good.

For others that didn't realize it was so simple. With a stand alone, it is even easier. This is about as complicated as the tables get with an aftermarket ECU.

Curtis GRM+ Memberand UltimaDork
12/20/19 10:50 a.m.

alfadriver said:
Can you be a lot more specific where you got this powertrain? And any parts codes on the module? Can look those up on HP tuners as Calvin is suggesting and go from there. Then you will have to go back and get the pedal for the throttle input. :)

Lets hope the easy button is there!

Yes I have the VIN and part numbers, but not handy at the moment. The whole story is I bought the engine about 4 years ago and got started building it. It's currently a longblock but I got busy with this "life" thing, moved, got a great job that takes a very disproportionate amount of my time, etc. All going in a 67 LeMans with a T56. I will need a different ECM anyway. I don't want the electronic throttle. I want a direct connection between my foot and the throttle plate. Already bought a 102mm TB. The electronic has just enough lag to be annoying. If I'm going to get serious about performance driving, I want to feel it. I also dig engineering simplicity. Fewer things to fail.

I finally have work to a point where I can take time for myself so I'm back at it. I'll get part numbers from the ECM soon, but here is what I know from memory;

LQ9 (stock shortblock) from an 02 (I think) Escalade with throttle by wire
AI fully CNC ported 243 LS6 heads (click for specs)
234/240 @ 50 cam, 113 LSA, I think .621" lift
11.3:1
.025" quench
1-7/8" full length headers
Aeromotive A1000 pump (but might also use a Holley electric I have since the A1000 is overkill)
55 lb injectors (FiTech)
T56, aluminum flywheel

The rest is inconsequential to the discussion.

Curtis GRM+ Memberand UltimaDork
12/20/19 10:51 a.m.

In reply to TheV8Kid :

Thank you for the tune! I was going to just pay someone to do it, but now it looks like it's rabbit hole time.

TheV8Kid Dork
12/20/19 11:54 a.m.

In reply to Curtis :

It will still need some tuning, but it at least has flex fuel working. Good luck.