Mike Frye

Woot.



(just ordered a new set of tires from Tire Rack too, will be installed by next week this time) New chips and new tires just in time for spring!!!

Jon B.

Ken, would this slight stutter be at idle? I'm confused about what should be perceiving as a stutter which I think I may also have.

PorKen

It's OK. I've started talking to myself after so much time road testing.

Besides overall better fueling, the main new feature is the semi-automatic compensation for (older) MAFs. If you adjust the CO screw ± for proper emissions at idle, WOT fueling should be kept in range, too. If you need yet more fuel at WOT (~1 point AFR), plug the LH (not the EZF) 'octane loop' plugs together.

Generally, as MAFs age, they output less voltage, but even rebuilt MAFs vary in output a tiny amount (sometimes they are off quite a bit ). This tiny change makes a large difference in fueling when multiplied by RPM. Stock, the CO screw changes part throttle fueling, but not noticeably at WOT. The factory deals with this by just making it very rich at full throttle/high rpm. I'm trying to keep a reasonable and consistent AFR at WOT (~12.5:1) to get that extra bit of HP.

It would have been better if I had changed the MAF scaling too, but there's only so much room in the tiny EPROM. As it is, I had to delete the code for injector cutoff on decel in order to make room for the 50+ bytes of hex code I added.

PorKen

A note for the manual shifter types. I found that because it runs so smoothly with the new chips that you can turn the idle screw in too far for idle recovery if you use the stock idle set routine. The idle will drop too far at times, then spring back up annoyingly, trying to recover.

I spent a good amount of time trying to 'fix' this in the chip, before realizing I could just back out the screw.

In short, with a 5-speed, set the CO @ the stock ~680 rpm, then turn the idle set screw out roughly two full turns. This will make about a 800 rpm idle (similar to GTs).

Jon B.

Ken, with your chips on my '86 I know Stan (mrMerlin) adjusted everything correctly. Also, the car is running a rebuilt MAF, and he did the adjustment after the fact. I'm just wondering if my "stutter" would go away with the new chip wipe like yours did.

It's a very small thing that I'm noticing at Idle, and I've also noticed the car doesn't like to chug around at close to idle speed in first. It seems whatever your "final" wipe seemed to fix this sort of thing.

PorKen

The V3.0 stutter was at light throttle, usually between 1800 and 2200 rpm.

I'm not sure what version you'd have installed, but the new one may fix the idle/low rpm problem. FWIW, my '86.5 auto has always had a 'tick' at idle when the O2 loop swings lean, even when it was stock.

...

Forgot to add this before - these are not as nice looking as the Bosch units, but they are pretty close for the price. There is one aftermarket version that looks awful. Don't know the seller.

http://cgi.ebay.com/ebaymotors/ws/eB...m=150568166980

Jon B.

I think I've got the light throttle stutter as well. I was playing with the car in the garage today and it seems that we are talking about the same thing.

Eturbo924

I am sure this has been asked to death... but never saw an answer... any chance you will be working on an S4 chip set?

BC

Wouldn't an adjustable FPR be a better choice for long range usage?

PorKen

No S4 chip.

AFPR could be good or bad. Good: it gives you more things to adjust. Bad: you need to adjust more things.

Darklands

Hello Ken,
no chance for bigger eproms?Is the injector cut off very bad for milage?Here in Germany fuel is very expensive. 1.50 € /l.
My engine runs great after the first 2-3 km.But after a cold start I have the feeling the engine has to much fuel,stalls and after lifting the throttle pedal goes on.
I have a new maf,new temp 2 sensor new plugs,new ignition wires ,new rotors and caps and the complete intake job done.
Also new ford motorsport inj. .

Cheers

Karsten

PorKen

No reasonable way to put a larger EPROM on the LH. I think you could change the EZF EPROM from a 2K byte 2716 to fully use the LH's 4K byte 2732 without too much trouble (just one wire to add on the board). If I turbo/supercharge someday, I may do that when I would swap the EZF MAP sensor for a 2 bar.

The injector cutoff should not affect mileage. Stock, it only kicks in if you lift >2100 rpm (when warm, >2800 when cold). With the V3 chip, at very high rpm with no load, the injectors almost cut off anyway, giving a >20:1 AFR. Below 3500 or so, the AFRs return to 14.7:1, as if it were idling.

The V3 chip fuels better at all temps. At most rpms, at part throttle (if the CO is adjusted properly), the AFR is right around 14.7 after the coolant gauge gets into the white box, even with the O2 sensor unplugged. It feels a bit more sporty with the sensor unplugged, as you are not fighting the O2 loop all the time. More like your S2, I imagine.

PorKen

Speaking of mileage...

I've made a running change (LH v3.2) of the behavior of the LH 'octane loop'. Now, when the plugs are connected, instead of the usual slow sine wave of ~13.5 to ~15.5 AFR to supply the different sections of the factory cats, AFR is a nearly flat 15.2~15.4 at part throttle/idle. Hopefully, this 'lean mode' will make for an extra mpg or so.

So far, I haven't seen any increase in coolant temps, and no ignition chip changes were needed. (Note, although there should be less HC, there may be a slight increase in NOx in this mode.)

Richter12x2

As awesome as your chips are from the stock computer - it makes me wonder what you'd be capable of if you used something like Megasquirt as a jumping off point and made entirely new snapin ECUs with upgraded components. Would that give you more room to play?
You absolutely cannot beat your current offering for the price point, especially though. I'll have to get with you about the upgrade as soon as I get my 928 together again (redoing interior and adding the AIR kit).

tilac999

OK then, how about an '85 ROW chip?