Tuning a Duratec...

[99Mystique ATX]

I have a non-svt duratec and i've been doing some research on tuning and from what i've found, optimum A/F is around 13-13.2:1 and max timing should be no more than 36 degrees. Is this information correct?

What about changes for mods? I have an optimized Ypipe, SVT exhaust with maganflow res and K&N filter/maf adaptor with heatshield. I also have a 3L taurus MAF, which I grabbed from the junkyard not because I need the higher flow of it but because my MAF went bad. The way the car is tuned right now is just the stock engine tuning with the Taurus MAF curve copied into the program. The tranny program, although not related runs higher shift pressures and slightly qucker shift times.

Also, when we tried to lower my idle, it didn't seem to change any. Maybe my guage is off?

I have a SCT 4-program chip and my buddy is an SCT dealer and has the full package.

EDIT: Forgot to say thanks in advance!

[warmonger]

I wouldn't shoot for 13.2:1 right off the bat. Not all cars will tolerate that level.
Start at 12.5:1 and lean out till you hit 13:1. If the car sounds really good under load you may go a bit leaner, but the difference on my car above 13:1 was very slight and better to be safer than sorry.
I had no issues running it that way because if I needed I could add fuel in just a few seconds.

[99Mystique ATX]

What about timing? Should I shoot for around 36 degrees max??

Also, i'd like to do a tune for regular gas, just so I don't have to run premium all the time. What changes do you make to run regular?? Is it less timing, a richer mix or a combination of both??

Thanks a lot for your help Warmonger!

[DemonSVT]

Also, i'd like to do a tune for regular gas, just so I don't have to run premium all the time. What changes do you make to run regular?? Is it less timing, a richer mix or a combination of both??

Unless you have, a version of, a flip chip you can not have it both ways.

Also you need to remember that you can not have ANY remnants of regular tractor piss in your tank to switch it to the "high octane" setting. That will just induce knock which kill far more timing that a "hot" program gives. A worst case scenario is it may kill more then just the timing if the octane difference is more then a few points. (4 points of octane is a very significant change, 6 points is huge!)
Also when switching between such different tunes the PCM's adaptive parameters are going to take a while to fine tune themselves. Likely more then a tank of fuel.

Then take into account that burning ethanol blends can distort the true octane rating of the fuel because of the large drop in engine efficiency. 5% to 10% is common these days and up to 5% does not need to be stated on the pump. Bastages!

In order to tune for multiple grades on separate tunes you will be doing a lot of datalogging and fine tuning. I mean weeks and longer. There is a reason why the OEM's have test mules they drive for thousands of miles in countless different types of weather conditions.


That is an awful lot of work to save roughly $2 a fill up. That's not even a meal at Taco Bell and the food's cheap there.

20,000 miles a year (50% over the average)
24 mpg (even my 3L gets 21/29 with my lead foot!)
.20 cent differential
$166 or .45 cents a day.

That's not even a soda/pop/candy from vendo-land.

For me it added up to $91 extra for the Entire Year. (a quarter a day!) No brainer from my point of view.

<un-targeting soap box>

I will never understand this whining over regular versus premium! 'nuff said.

</end simple math lesson back to your regular tuning thread>

[99Mystique ATX]

I do quite a bit of driving, probably 20-25k/yr and that was my concern with that, but when you put it into perspective, it really isn't that much different between the two...

I have a Superchip that has the switch so you can choose between 4 programs. But, put into perspective, there's not much point in me doing the two tunes, just one good premium tune.


MMM... Taco Bell...

[warmonger]

I...

MMM... Taco Bell...

lol

I'd tune for whatever gas is in your tank and advance the timing at various rpms until you get things cropping up that you don't like.
Assuming you don't knock, too much timing causes a reduction in power or generally rough feel to the engine. I'd go no more than 2* at a time at various 500rpm increments until you find you've made the most power.
Really takes a while

[DemonSVT]

really takes a while

Wow I was more long winded then Tom and his Greg-like 4 word answer. Maybe I'm not feeling too well.

[warmonger]

Hahaha.

Bastage!