Digital Tuning new inj / maf - need tune?

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
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Maryland
Hi all, been a while since I mingled here but here we go again.

A little history > My previous setup with 30lb injectors was custom tuned via SCT chip. I did not run an FMU. Can anyone tell me how the chip references boost in this type of setup? Am I correct it took signal from the MAF and used that to add fuel under boost? Whatever it did, it worked and would add the fuel needed to keep the AF in the 11's under boost.

Recently I changed from 30lb inj to 42's. I sent my MAF in to Pro-M and had it recalibrated for the 42's and paid extra for the 30 point data sheet. I put the 42 lb injectors and recalibrated MAF in. It runs fine under normal driving conditions but when I hammer down and go into boost, the fuel is no longer there. I have a wideband and I can clearly see, as boost comes in and increases, the AF gets increasingly lean. I mean way lean to the point of detonation.

I will call Pro-M and see what they can tell me. Meanwhile, is it normal to need a redo the chip tune when recalibrating MAF and upsizing injectors? Remember, no FMU, but management via custom tune.
 
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From what I know the chip was tuned to your set up, change the set up change the tune on the chip.
This is part of the reason why aftermarket diy ecus have become so popular, if you make any changes you can
adjust your tune without paying someone to do it.
Although knowing how and what to adjust takes some time to learn.
 
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Found one local shop that lists $500 for dyno tuning. Heck, thats half way to a Megasquirt and diy tuning.
That's one of the reasons an aftermarket ecu is so tempting.
I'm not saying just because you changed your injectors you should ditch your stock ecu but if you want the ability to tune
yourself this might give you an excuse.
I've been really happy with my PimpXS , still learning but a91what on this forum is a huge help.
 
I might try a Moates Jaybird along with their binary software to tune my SCT 6600 chip myself. I sent Moates a message to see if this will work. I'll let you know what I hear.

In other thoughts, I really like the features of the Megasquirt PNP2. I really like the knock sensor capability of it. It would be nice to have that on guard to cut timing automatically if anything went wrong.

Tuners in my area are so busy they dont even answer the phone. They have not returned messages either. I think they're steeped in the newer stuff. When I leave a message and say, "92 Foxbody with SCT chip", they probably are thinking...........pass
 
Moates responded fast. Although they recommend their chips primarily, they said the Jaybird along with their binary software will allow me to tune the SCT 6600. But if I used their Quarterhorse chip instead of the SCT, I could data log on a laptop and really have a more focused picture of whats happening.

Heck, for less than one dyno tuning session I can go with the Moates stuff and do it all my self, repeatedly as needed. Just need to get through the learning curve.

So, the Moates route would cost me about $400 if I wanted the Quarterhourse for data logging.

Or, Megasquirt would be $800 (more features is the lure here). And, with this route I could sell the SCT, sell the Pro M MAF and sell the refurbished A9L. I could probably get a total of $500 for all those parts. It's looking better and better for the Megasquirt route
 
I ran a Moates quaterhorse originally, had a tune put on it by dirty dirty racing and my car ran really well but
I never invested the time to learn binary editor.
Ended up going the PimpXS route (MS3) , imo it's pretty user friendly if you invest some time.
 
Dyno tune chips are becoming a thing of the past. With the MS stuff and the holley terminator x stuff being so cheap its more cost effective to go aftermarket standalone ecu. I sold my anderson pms 4 for $425 and bought a holley terminator x (937f) kit for $1149.

To answer your question, you can't change maf's and injectors w/o redoing the chip. More cost effective to go aftermarket ecu.
 
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I think ill go with Moates QH. Theyre support looks good and ill also get the binary editor for Ford And the Jaybird to burn my own tunes.

My reason is I have two Foxbody cars and with a $400 cost for the Moates stuff ill be able to tune both cars as many times I want. The QH can data log in real time. Ill first put the QH in the convertible and data log to see whats its doing. Then ill take that info and use it to write a data map in the software editor. I’ll use the Jaybird to burn that map on to the SCT 6600 chip i currently have in the LX, and swap that SCT in to the convertible. Finally, ill use the QH to data log In the LX, take the info and use QH in the LX.

So, combined with what i already have, $400 gets me full DIY tuning capability for both cars. I also currently have two fresh A9Ls and one fresh A9P so im not in need to replace those anytime soon. Good factory ecu’s are as reliable as they come.

Local tuners want $500 just to get one car even in the tuning bay, if you can wait for their scarce availability. Their voicemail actually said, “we’re so busy we dont answer the phone so leave a message and we’ll contact you“. I left a message two weeks ago and have yet to hear back.
 
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I think ill go with Moates QH. Theyre support looks good and ill also get the binary editor for Ford And the Jaybird to burn my own tunes.

My reason is I have two Foxbody cars and with a $400 cost for the Moates stuff ill be able to tune both cars as many times I want. The QH can data log in real time. Ill first put the QH in the convertible and data log to see whats its doing. Then ill take that info and use it to write a data map in the software editor. I’ll use the Jaybird to burn that map on to the SCT 6600 chip i currently have in the LX, and swap that SCT in to the convertible. Finally, ill use the QH to data log In the LX, take the info and use QH in the LX.

So, combined with what i already have, $400 gets me full DIY tuning capability for both cars. I also currently have two fresh A9Ls and one fresh A9P so im not in need to replace those anytime soon. Good factory ecu’s are as reliable as they come.

Local tuners want $500 just to get one car even in the tuning bay, if you can wait for their scarce availability. Their voicemail actually said, “we’re so busy we dont answer the phone so leave a message and we’ll contact you“. I left a message two weeks ago and have yet to hear back.
I'd like to know what you are getting and see some pics of the Moates stuff.I currently don't need tuning stuff but as l do all my own repairs and I'm cheap as he'll that price seems right up my alley.If you can do before and after vids that would help my old ass.Thanks.
 
I just won an ebay auction for Moates tuning stuff. Even though I was considering Megasquirt, I wanted to see if I could get a deal on this Moates stuff.

I think I got a good deal. Paid $307 all included for these items listed below. Now I can buy blank chips for $75 each and tune as many cars in these platforms I choose to.

Quarter horse (retails $249.99)

Jaybird. (Retails $75.00)

Optoisolator. (Retails $40.00)

Binary editor w/dongle (retails $171.00)
 
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You got a good deal !
I still have my quarter horse and Binary editor/dongle, I should probably sell it.
What is the optoisolator for ?

Looks like it helps maintain the usb signal so you dont get booted in the middle of logging data or making adjustments. Heres the info from Moates on it.

 
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