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Discussion Starter · #1 · (Edited)
Been wanting to ask, but was hesitant. Hopefully this won't be the dumbest question of the day/week ..

My Cobra is bone stock still, okay, maybe the radio isn't. From what I read the processor retards timing between up shifts (downshifts?) to preserve the transmission from back then warranty repairs on the 94/95 cars. Are other years programmed this way? Even though I'm easy on the car I just don't like that idea a whole lot that it wants to pull the timing back.

I remember taking a 9 month computer course many years ago. It was Cobol, Fortran, and some other language that I don't recall now. Never put it to use except to make a pong game on my Commodore Vic 20- maybe it was a 64. Anyway, the programs always included instructions like if, and, or, then, ... So what inputs is the processor interpreting to make a decision about the timing?

Now ... Could this retard be "tuned" out by simply cutting a circuit board trace or otherwise fooling the ECU to not know that I've changed gears?

I should add- no added chips or trips to the dyno shop.
 

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Been wanting to ask, but was hesitant. Hopefully this won't be the dumbest question of the day/week ..

My Cobra is bone stock still, okay, maybe the radio isn't. From what I read the processor retards timing between up shifts (downshifts?) to preserve the transmission from back then warranty repairs on the 94/95 cars. Are other years programmed this way? Even though I'm easy on the car I just don't like that idea a whole lot that it wants to pull the timing back.

I remember taking a 9 month computer course many years ago. It was Cobol, Fortran, and some other language that I don't recall now. Never put it to use except to make a pong game on my Commodore Vic 20- maybe it was a 64. Anyway, the programs always included instructions like if, and, or, then, ... So what inputs is the processor interpreting to make a decision about the timing?

Now ... Could this retard be "tuned" out by simply cutting a circuit board trace or otherwise fooling the ECU to not know that I've changed gears?

I should add- no added chips or trips to the dyno shop.
Yes, it can be tuned out with a TweecerRT, Moates quarter horse, or SCT chip that is burnt. You'd place that module on the back of the factory computer. There's no other ways to alter the timing curve in the EEC. And yes, the retard is the ECU only commands about 27-28* total timing from 4000rpm which is about 6* short of where you could be. This is why there's so much power to be gained by simply advancing your distributor from the stock 10* to 14-15* you just need to make sure if you do this you only run 91 or better. Reason for this is you could run into pinging/detonation issues at low-mid RPM where the timing curve is more aggressive.
 

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As mentioned above, use 93 octane fuel and set your base timing to 15 degrees. 100x easier than messing with the ECU....
 

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Discussion Starter · #4 ·
Thanks fellas. Yes, base timing, spout removed, is at 14 degrees. I've had no detonation issues even experimenting with 89, may have even tried 87 (?). Makes me now wonder if it truly is at 14, so maybe I'll re-time it by ear in the spring. The cost of fuel is immaterial (at the moment) as I only put less than 2500 miles/yr on the car- only in good weather. I don't care what fuel costs. Always drive with engine speed up, never lug it down. Alternate between 91 and 93 at 1/2 tank. At 9:1 worry that 93 isn't compressed enough. Is it?

Still wondering about that if, and, or, then instruction types- if such instructions are still current. No clue on that. Just curious. Definitely won't go the chip route or have someone tune the car, so many horror stories and thousands of $$ spent only to read about the inevitable driveability issues- for guys like me that aren't up on this and now lack the ability to do it themselves. If I could carb it and be legal it would already be done. I grew up with carbs and had no issues- summer or winter. Change the heads and cam, no problem. Dual point centrifugal advance distributor and dual quads? Done. A screwdriver and you were good to go. Wouldn't argue that EFI and processors and associated input sensors aren't better and more efficient, it's just about that co$t when you want to add a little more.

Yeah, the old conservative white guy got off track. Just wanting to cut to the "trace' and keep the shift a secret.
 

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Thanks fellas. Yes, base timing, spout removed, is at 14 degrees. I've had no detonation issues even experimenting with 89, may have even tried 87 (?). Makes me now wonder if it truly is at 14, so maybe I'll re-time it by ear in the spring. The cost of fuel is immaterial (at the moment) as I only put less than 2500 miles/yr on the car- only in good weather. I don't care what fuel costs. Always drive with engine speed up, never lug it down. Alternate between 91 and 93 at 1/2 tank. At 9:1 worry that 93 isn't compressed enough. Is it?

Still wondering about that if, and, or, then instruction types- if such instructions are still current. No clue on that. Just curious. Definitely won't go the chip route or have someone tune the car, so many horror stories and thousands of $$ spent only to read about the inevitable driveability issues.
Most boosted cars now days are 10:1 or even more. You'll likely be fine. If you are unsure of timing you could get a piston stop and check. It's common the stock balancer rings separate from the rubber and do weird things.

I don't get your question. It's an EEC-IV computer. There's not much point having your car tuned being 100% stock Ford already did that. You could easily have a custom chip burnt that ONLY changes that timing table that would not effect anything else.
 

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Discussion Starter · #6 · (Edited)
What I'm asking to make happen is no doubt wishful thinking based on some computer logic I learned some 38 years ago, and then subsequently forgot. There has to be more than one "input" condition to be present for the processor to decide to retard the timing during (or immediately thereafter?) the shift into another gear. Since an electro-mechanical switch from the clutch isn't in play then what/where are the "if" conditions that cause the processor to "then" make this decision? I'm sure one would be engine vacuum, what might be the others?

Added- And the TPS if you can override the retard by power shifting as I read. Not something I would ever do though.
 

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What I'm asking to make happen is no doubt wishful thinking based on some computer logic I learned some 38 years ago, and then subsequently forgot. There has to be more than one "input" condition to be present for the processor to decide to retard the timing during (or immediately thereafter?) the shift into another gear. Since an electro-mechanical switch from the clutch isn't in play then what/where are the "if" conditions that cause the processor to "then" make this decision? I'm sure one would be engine vacuum, what might be the others?

Added- And the TPS if you can override the retard by power shifting as I read. Not something I would ever do though.
The timing I mentioned is hard coded into the ECU based on load and RPM. May want to google a stock timing table and look. About the only way to trick it would be to make your IAT sensor think it’s -20 outside. But then other problems with drive ability would occur like waaaay too rich. Which would slow you down. Tune it the right way with the methods above or don’t worry and leave it be.
 

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I think the point we are all trying to make is you can add timing very easily by rotating the distributor, which it appears you have already done if you are running 14 degrees base.

You have a bone stock 94 cobra which makes about 215 wheel horsepower on a good day and puts the power through a 2.73 or 3.08 gear (not sure which). So the fact that you are willing to try and reprogram the ECU to try and add a few more degrees of timing in a car that may make 1 more foot of torque on the shifts seems to be about the biggest waste of money mod there is.

You want to go faster, put in some 3:73s and you could easily gap any stock 94 cobra with more timing on the shifts....
 
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Discussion Starter · #9 ·
Appreciate the replies fellas. Agreed, definitely don't want to reprogram the ECU, was just wondering what all goes into the timing decision process and whether or not it could be easily defeated. Certainly wouldn't throw more than a few dollars at it. Maybe there a flow chart available somewhere, I have a friend who works for IBM that I've built a few audio amplifiers for, he owes me ...

Gears are out, the 3:08's must stay because the 3;35 first gear ratio is obscene IMO. Should be in the 2:40 territory, makes for a much more pleasant experience. One recent built Fox body I had was with 4:10's, only good for frying the tires off. If you've ever driven a so called "muscle" car with a CR Muncie 2:20 low from back in the day you might agree.
 

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As a side note... 25 years is a long time for a stock harmonic balancer. Many have spun on the hub with way less time on the clock. Before you keep experimenting with timing, I would replace it with a good aftermarket, like a powerbond SFI or something similar. This will allow you to at least give you the piece of mind that your timing base is at least correct.
 

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Discussion Starter · #11 ·
Thanks for that input. Yes, the balancer was replaced last year at 63K with a Powerbond. I even posted up a thread about that, with photos, as I was completely shocked at the HUGE difference it made in engine feel.

 
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