sho_sc
New Member
I'm really calling this one from memory, but the last cell in the stock timing curve is 33 at 7300 RPM??
Need help analyzing log file.
- Thread starter Lupo
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I'm really calling this one from memory, but the last cell in the stock timing curve is 33 at 7300 RPM??
sho_sc
New Member
That's the only thing I could figure out he was doing by looking at his tunes. He knew that the knock sensor was pull timing, so he through in what he thought the curve should be +7. That way the knock sensor would pull out the max and you would still have a good running SHO. The problem is/was you are depending on the knock sensor to work well. Plus, it takes "awhile" after the knock event for the EEC to start pulling timing enough to stop the detenotion. e.g. come around turn 7 at 5K RPM in 3rd gear at part throttle ... "wallop on it", dentonation occurs the EEC pulls 0.25 degrees of timing out, then it occurs again, the EEC pulls 0.5 more degress of timing, but not before breaking a ring landing ......... and then simultaneously 3rd gear breaks. :laugh_ti:
Stock timing curve has 33 @ 7600 and up.
yup 33 just checked it. Is the WOT spark vs rpm the best way to pull timing? i figured it was and thats where i added timing for my n/a tune. i havent built a nitrous tune yet.
right now ive got my n/a tune set to 35* from about 4800 and up. i think my nitrous tune im going set at 29* from then on.
i want to richen up the tune at that point also, which function is best and how much should i add first? (ill be doing this with a wideband)
sorry for the hijack
right now ive got my n/a tune set to 35* from about 4800 and up. i think my nitrous tune im going set at 29* from then on.
i want to richen up the tune at that point also, which function is best and how much should i add first? (ill be doing this with a wideband)
sorry for the hijack
Lupo
New Member
Ok, I set the FP to 44psi. What would be the reason of lowering the higher slope number to 62? This would make it richer in low load conditions?
Lupo
New Member
PIP is profile iginition pickup, and hitting that limit will **** the motor entirely until you restart. It should always be higher than your RPM limit for obvious reasons.
Ted B programmed a LPM for my truck that had a 8000rpm limit, but left the PIP stock at 8000, instead of raising it to 8500+.
Guess what happened when the truck hit 8000rpm?
So if you raise you RPM limit, you also should raise your PIP limit above the RPM limit. For example, if you set your RPM limit 8000, your PIP should be 8500+
Stock is 7300RPM limit, and 8000PIP limit.
In Caledit, RPM and PIP limits are set in "tics". Just take the number 8,300,000, and divide it with the desired RPM to get the proper tics.
Part throttle spark advance does exactly what it says. It applies to part throttle/non-WOT.
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jonheese
Used-To-Know-It-All
Small correction, based on the values at the bottom of Josh's TwEECer page, the factor is actually a lot closer to 8,330,000 tics*RPM.
Regards,
Jon Heese
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Lupo
New Member
Yea, thats right. I was just remembering from off of the top of my head. But it's /RPM not *RPM
jonheese
Used-To-Know-It-All
Hmmm... No, I'm pretty sure it's tics*RPM.Yea, thats right. I was just remembering from off of the top of my head. But it's /RPM not *RPM
Look at it this way:
8,330,00 tics*RPM / 7000 RPM = 1190 tics
8,330,00 tics*RPM / 1190 tics = 7000 RPM
The units have to be tics*RPM to work out.
Regards,
Jon Heese
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Lupo
New Member
Yes, you are right. tics*rpm must = 8,330,000.
In your previous post, I misunderstood your quote as 8,330,000tics*RPM. You needed a period, or comma or "=" after the 8,330,000.
"Small correction, based on the values at the bottom of Josh's TwEECer page, the factor is actually a lot closer to 8,330,000 tics*RPM."
Anways, the correct number is 8,330,000 like you said.
jonheese
Used-To-Know-It-All
Wait, what? Where did you get an equals sign? "Tics*RPM" is a unit, not a command.
I was talking about the units of the constant itself. "8,330,000 tics*RPM", like "26 ft*lbs". No equals sign, just one term with units attached.
Regards,
Jon Heese
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sho_sc
New Member
From what I have read and experienced, the "newer style" injectors are more efficient at low pulse widths than the ones from the late-80s. Clint, of EEC Analyzer fame, suggests 20-25% difference between the slopes.
Now for the reason that, especially with those settings, your SHO will run rich at idle and low speeds:
Injector Offset vs Battery Voltage .. which is an adder done after the EEC does all of its calculations to the injector pulse width. It is a measurement of how long it takes for the injector to open/close once the command is give by the EEC. This measurement includes mechanical and electric response time and is reported in ms. Incorrect Injector Offset settings will show up at low pulse widths, idle and cruise. With BIG injectors, you are probably idling around 1.35 ms. The original X2J Ford tune has the Offset @ 14v set to 1.1875ms which it way too big for modern Big injectors. (that is almost the same as the idle pulse width itself). I would suggest reducing that table to 50% of its original settings ... my current table is set to ~25% of the original Ford settings, however I think mine is a little "too lean".
Another note: I'm currently tuning my SHO with an 80mm Lightning MAF. I've had a problem with my PRO-M MAF and just trying to trouble shoot. Using Josh's numbers (MAF Transfer Curve for the 80mm Lightning) within TwEECer, all I've done is to add 7% to the curve above 3.0v and it looks to be really close ... however, I've not done that much tuning yet.
Lupo
New Member
So Clint suggests removing 20-25% of the offset value, so value for 14v (1.1875 stock) should be set to .890625?
And you yourself would suggest a 50% reduction of the same value to .59375?
So...what I am understanding is this: With the new injectors (accel 48#s like I have), the offset values for stock are too high, causing a rich condition at PT and idle?
Your own current setting is -25% from stock, and you feel you are going lean? Which injectors are you using?
jonheese
Used-To-Know-It-All
Don't confuse injector slopes with injector offset values.
Clint suggests 20-25% difference between the injector slopes. Ransom suggests reducing the injector offset values to 50% for modern big injectors. Two different things.
Sounds right to me. If the response time is considerably quicker then the table predicts (which is likely to be true with "modern" injectors), then the injectors will be open for that much longer, unbeknownst to the EEC, thus rich.
Regards,
Jon Heese
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sho_sc
New Member
Let me clarify ....
The low slope should be around 20 -25% more than the high slope via Clint. e.g. 48/60 [most folks have the high slope higher because they don't have the Injector Offset settings correct]
Injector Offset Vs Battery Voltage settings should be adjusted to reflect 50% of what the orginal Ford X2J tune shows as a starting point. e.g. Ford-14v=1.1875ms 48# Accel-14v=0.6ms
[this setting being too large is what can cause rich idle and low speed]
Mine is actually set to a 75% reduction or more. e.g. 14v=0.28125ms
I use 63# Siemens injectors and I run my fuel pressure at 48.5# making them equivalnet to 66lbers. My injector slope settings are ~66/71. But since I must add ~7% to the low end of the MAF curve (mainly idle range), I suspect that my Injector Offset settings are a little low.
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Lupo
New Member
You are right, I wasn't paying attention to the "slopes" part. Duh...
