351W with FAST EZ-EFI...it lives...watch the video!

[sick88tbird]

to be more exact... EZ-EFI is a sub-brand (or line of products) under the FAST brand name. It was made initially for the 4-injector 4-barrel EFI system that bolts on to most 4-barrel type intake manifolds. Hence the questions about models/etc.

Well said.

And yes King, that was the first time I saw a 2-door panther...and when I moved to SC I could no longer tolerate the worn out, rusted t-bird anymore and went on a year long mission to find a decent 2-door CV which involved a few trips to Atlanta to look at ragged out junk until I came upon this one...while it has many flaws still, it's the best one I could find within a 3-4hr drive in my price range....and the fact that it has less rust than 2-3yr old cars in Jersey, well, that's just icing on the cake.

Thanks,
Don

[torquelover]

Sweet. The sound reminds me of my old 351 P72. How's the driveability?

[King_V]

Definitely keep us informed on how the system's learning/adapting goes - and the improvements in how the beast runs!

[sick88tbird]

It's learning more and more...it's a little grumpy in open loop, but as soon as it hits 140* it starts learning...cold starts have improved but the system doesn't go into learning until 140*...??? I won't complain...I do have some occasional idle surge and I think it's due to the current timing curve...hopefully this weekend I can recurve it and see how it does...it's got stupid heavy springs and most likely a 21L advance slot(which = 42* mechanical advance) which will have to be welded up to narrow the slot, I think 20-24* mechanical advance would be ideal with 10-12* initial and the vacuum can will have to be tuned by feel going down the road.

-Don

[King_V]

Hm, yeah, I guess it doesn't learn in open-loop (how would it know what to adjust without feedback from the O2 sensors)? On the other hand, I'd thought that once it starts getting info from the O2 sensors, it'd be able to compensate regardless of temperature....

Does the open-loop mode have to maybe be manually reprogrammed? I've never really worked with any non-stock fuel-injection systems, and only know a bit of theory at best.

[sick88tbird]

I actually made a mistake in my last post...it pretty much is NEVER in open loop...as soon as the wideband o2 sensor is heated up (about 10-15 seconds after key-on) it's looking at it to make fuel adjustments...it's just the adaptive learning that doesn't start until 140*. It has 4 different live data screens and one of the screens has o2c%, which means the fuel correction percentage, kinda like watching short term fuel trim through a scanner on an OBD-II car, sometimes it's positive, sometimes it's negative and it's working to keep the a/f ratio where I set it to be...I set idle a/f to 13.9, wot a/f to 12.8 and cruise to 14.0. I don't know how right those numbers are, I think wot a/f is pretty decent, I'm not a professional tuner so there is a learning curve for me as well as the fuel injection system...lol.

I really need to get the timing curve right though before getting crazy with trying different a/f ratios...both can have a profound affect on idle quality and drivability, that much I know for sure. I bumped the timing a hair last week and now around 3500-3800 at wot it's pinging...I'm pretty sure it has the 21L advance arm which will be getting welded up and basically made into a 10L or 13L arm...or I'll weld one side up to a 10 and the other side to a 13, that way I can see which one is better for my combination. I'd be willing to bet that right now, one side is a 21 and the other is an 18...maybe a 15 at best, which is still too much.

It currently feels like there is not enough timing down low and then when the heavy spring tries to let the party start, there is too much timing...with the right curve, it should pick up on both ends...I'll keep everyone posted.

-Don

[sick88tbird]

Oh buddy, it's on now! I took the duraspark distributor apart early today expecting difficulty....it was uber-easy!(being only 2 weeks old helps too). I found that I indeed had a 21L arm on one side and a 16L on the other and it was using the 16L...so 32* of mechanical advance...I found the measurements for all the arms and proceeded to weld up both sides, one to a 10L and the other to a 12L...of course now I forget which one I'm using...lol...I think the 10L side and I bumped my base timing to 10*. It should work out to 30* total, but it's actually showing 32-ish, which is fine for me...and I used the two yellow springs from the Crane kit to get the mechanical at full advance by 2600-ish and it's close.

And wouldn't you know it...so far, no annoying idle oscillations...oh and the vacuum can from the Crane kit is much smaller and instead of 45* at idle with it plugged in(the old can) it's now around 35* which I like. However, if I plan to put anymore base timing in it, I have to pull the distributor and turn it a tooth or two...no big deal, I suppose.

Daddy likes!

-Don

[King_V]

Awesome, great to hear!

As to A/F ratios . . now, again, keep in mind that I know theory, not practice, but I could've sworn I'd come across reading that - for idle you'd actually want the stoichiometric 14.7 or close to it . . light cruise you could actually do something in the low 15.x range, and, well, of course WOT has to be a tad on the rich side, though you'd have to experiment a bit to see what the engine likes best in that regard.

Heck, I remember an older car or two (carbureted, early 70s) where the underhood stickers said to set the idle mixture to 14.7:1.... though how they expected you to know when you'd hit that ratio is beyond me...

Take this with a boulder of salt.....

[sick88tbird]

The only reason I haven't gone leaner on cruise is because of how the FAST system works...past 50% throttle opening it starts to interpolate between cruise a/f and wot a/f...basically meaning the closer you get to WOT, the closer your a/f gets to your preset WOT a/f ratio.

Like I said, I still have a lot to learn about tuning it...at least it's a forgiving system. I may try a leaner idle...my only concern is then cold starts...it'll fire up and run at 1400-1600rpm for a second and when it starts to come down the a/f pegs 15.9 and if it doesn't stall, it comes damn close and it'll do that 2-3 times(if it doesn't stall) before stabilizing. The occasional idle surge is back, but RARE and very easy to make stop...when it does it, I just barely crack the throttle to bring it up to about 1000rpm and ease it back down and it's good....I still think that and the cold start issue is a matter of the idle getting whacked around from the vacuum advance swinging the timing all around when the IAC is going haywire trying to control idle speed...IDK for sure...just a theory.

Currently replacing t-stat gasket(cheapo one started leaking) and reclocking the distributor so I can get a little more advance out of it...10* initial was it before the distributor hit the t-stat area of the intake.

Good times,
Don

[King_V]

Hrm, that is sort of odd... when you mean cold starts, do you mean behavior before the O2 sensors are warm enough to give a reading? Or just the sub-140-degree behavior? Eh, may not even be an important question, it's more my own curiosity about how the EZ-EFI system works....

[sick88tbird]

Cold starts under about 80* coolant temp are a little sketchy. I'm giving it a little throttle when I key it on now to try and give it an extra shot of fuel and it seems to be helping...but on cold starts, the o2 correction factor is like +25-30%...meaning it's adding that much fuel to maintain my 13.9 idle a/f ratio....once it's fully warmed up it's like -1-5%, so at hot idle, it's taking a little fuel out. I'm thinking about moving the IAT sensor to the air box...the FAST tech guys say it's fine in the intake even though it's getting to 170-180* cruising around town but I still don't care for it.

-Don

[sly]

+1 to the air box. Mass air systems in general seem to be happier about it there.

[sick88tbird]

+1 to the air box. Mass air systems in general seem to be happier about it there.

But what about aftermarket Speed Density based systems? lol I believe that there is certain programming written in the computer to do certain things during very high IAT readings...yeah it's got adaptive learning, but I think it may be easier (and quicker) for it to learn if it doesn't have to try to "unlearn" certain base parameters.

Timing update...I set it back to about 9* initial and 30-31* total mechanical...ran like a raped ape from 1st through 3rd(to 4200rpm) but in 4th around 3800rpm, I had the slightest little pinging(no noticable power loss) so I immediately backed off...and my mechanical is at full advance by 3000rpm(give or take a little), so I'm thinking about making my WOT a/f a little richer...probably go from 12.8 to 12.2-12.4....it's hard to tune WOT on the street through 4th gear...in a small town...lol. About 3/4 of the fuel in the tank is 93 and the rest is 87...I think this car is destined to chug premium from here on out.

-Don

[sly]

Mass air systems seem to use head temp sensors for that or expect the driver to know that when the steam starts coming out, to turn it off.

[King_V]

Can you ask customer support about it? I don't really know much about these things, but I've read that the help/support that comes with the purchase of EZ-EFI is top notch.

Unless, of course, that's one of those pay-per-incident type of things, which I can't imagine will be much fun...