When tuning what should be turned off??

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Turk
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When tuning what should be turned off??

Post by Turk »

Megasquirt v2.2

Ok well I have had trouble tuning for a while now, and want to clear things up to take out variables of what im doing wrong.

1. I have disconnected my Adjustable Fuel pressure regulator from vaccum.
2. Should I turn off accel enrichments (or something?) while tuning?
3. SHould I turn off the Decel stuff as well?
4. I have turned off EGO correction.

Also is it possible for me to be at 7.4 AFR under boost and not blow visible rich smoke? Im still trying to decide whether I am getting good readings out of my LC-1. With my new ground setup I think they are much more reasonable numbers but Im still not 100%.

Cheers
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Fred
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Re: When tuning what should be turned off??

Post by Fred »

Ummm,
  1. You need a vac reference to the fuel pressure regulator or it will not function. This should be setup the same always. Whether you use an adjustable and whether it is rising rate or 1:1 or not are different things. 1:1 is the correct choice, rising rate = fail. You must have the vac ref on that and it must be from the plenum after the throttle.
  2. Yes, in the early stages of tuning you should have accel enrich off or very mild. Accompany that with smooth throttle use so as to not require it.
  3. Yes, decel cut is something you add in after your tune is mint.
  4. Good, EGO should be off until you have a stable base tune at the very least. Furthermore it should be set to only operate in low load stable regions, not in boost, not at high revs.
  5. I strongly doubt your ignition (unless it is a good CDI) would run the engine at all at 7.4:1 AFR, that is dripping wet, black smoking rich. Sounds like the reading is wrong. Have you checked on the LC1 software to ensure it isn't a connection/ms interface issue? Where is the sensor mounted? Angle? Distance from engine/turbo?
  6. NO SUCH THING AS MS v2.2 :-p And you should know better than that! What the man has is ms1 on a 2.2 board with some firmware that he hasn't told us about. Turk, which firmware?
Hope that helps ;-)

Fred.
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Turk
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Re: When tuning what should be turned off??

Post by Turk »

1. It is a 1:1 fuel pressure reg. I need a better vac for my Blow off valve then (yer yer aftermarket ones are shit I know). It is using a T piece off the intake manifold which is shared/ T'd off by the Blow off valve, wastegate, boost gauge, MAP sensor, electronic boost controller ie way too much shit I figure.

2,3,4. Sweet and that is easy enough cheers.

5. I am using the LC-1's gauge for that reading, I never got it to interface with Megasquirt properly. I have tried so many things with wiring the LC-1 and just when I think it is working, it isn't. The sensor is on the dump pipe before the cat, about 50cm (or more) after the turbo. Positioned at like 9-10 o'clock.

My wiring on the LC-1 is like this:

Heater ground and the other ground (???) on one lug, bolted to chassis that has been sandpapered back.

Megasquirt ground, LC-1 gauge ground, gauge headlight reference, on another lug bolted to the same panel (behind gearstick), about 8cm over.

6. Been so long since I have talked about anything megasquirt related. MS1 with 2.2pcb and im not sure on the firmware. Would have to go check. Whatever Radar gave me :).

Cheers man. I would love to get the mx6 back as my daily driver, I am sick of driving a 30 year old car even if it is fun in the rain while my not as old car sits in the garage. Not having the "must work on it otherwise cant drive to work tomorow" motivation has kept it virtually untouched for the last 6 months.
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Fred
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Re: When tuning what should be turned off??

Post by Fred »

Innovate say that the two grounds should be at the same place. I don't necessarily subscribe to this strong and clear manufacturer recommendation, BUT, if your grounds are at different places and the place they are at is dodgy, this could be your problem.

Could it have been calibrated in something other than fresh air? (which way would this make the reading go?)

I'm outa ideas for now, good luck.

Fred.
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WTDeuce
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Re: When tuning what should be turned off??

Post by WTDeuce »

For force inducted cars, the FPR should always stay connected. 1:1 just means its going to go up 1 PSI for each PSI of boost. Disconnecting it results in incorrect fuel delivery when on boost which is gonna throw your tune off.
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Fred
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Re: When tuning what should be turned off??

Post by Fred »

WTDeuce wrote:For ALL cars, the FPR should always stay connected. 1:1 just means its going to go up 1 PSI for each PSI of boost. Disconnecting it results in incorrect fuel delivery when on boost which is gonna throw your tune off.
Fixed! (or can you think of some obscure counter example? seems to me that the statement implies that the manufacturer had it connected, and if that is true it is also true that it should stay connected or the fueling will be wrong)

If it isn't, your fuel delivery IS wrong. With a non 1:1 you get a non linear fuel flow with respect to boost, not ideal. Just a hack for injectors that are too small.

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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