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Posting here to subscribe. I read through these posts and I can add a few things.
They recommend the GM 3 bar supercharger MAP sensor number 12592525. I believe if you use a different sensor, you'll need to compensate for it in the software.
The ECM provided with these kits are identical. If you don't use a 4L60/80 transmission, the ECM doesn't care. You'd only need a VSS input if you're using the transmission control.
It's impossible to make a harness that will fit every installation. It's pretty long. I think the IAC cable was like four feet from the main harness.
FiTech will NOT provide a harness schematic.
The installation manual meticulously describes the fuel pump pulse wave control and how to adjust it to vary the fuel pump voltage. But the fuel pump comes off a standard contact relay, not a solid state relay. Like pulling teeth, they finally admitted it's not controlled, just on or off through the relay.
I've spoken with Mike who was nice but he passed me to Bryce, saying he was the Ultimate LS "guy". He had a few things wrong and didn't have answers. Maybe I'll ask for Kirk next time?
Thus far, their phone & email support sucks.
My engine? I'm the oddball here, a 496 big block outfitted with all LS1 sensors and hardware.
After talking with Kirk at FItech I was told I could run the GM 2 bar map sensor and wouldn't have to change anything on the PCM. Voltage changes for atmospshere depending on the sensor (1,2,3 bar) so I'm not sure how that works. Worst case is a change of the MAP value and the scalar like in HP tuners.
I think dmracing was having a ignition issue after the swap and that's why there is the idle issue.
No Ignition problem. Brand new coils. I was told by Fitech after sending them the video I need to set my IAC. They sent me the direction on how to do it.
No Ignition problem. Brand new coils. I was told by Fitech after sending them the video I need to set my IAC. They sent me the direction on how to do it.
I feel like if they had the ability to set a two-step or something like that I would go with this setup on mine. But the MS Gold box from EFI source is my current front runner because of the amount of different options it has available(while more expensive as well $1225), but its plug and play and he can preload a mass array of tunes on it prior to it getting to you so it makes startup much easier. I've shot them an email and asked about the future and if there will be an ability for a 2 step, but I don't think ill hear back from FItech anytime soon with all the com's issues you guys are having. But ill be running a mostly stock Gen IV 4.8, 7875 t4 setup with a cam and springs, with the factory truck intake. So we will see, maybe if you guys have some good success with it ill hold back on the two step for now seeing as its a majority street car, with only the occasional trip to the track,
I feel like if they had the ability to set a two-step or something like that I would go with this setup on mine. But the MS Gold box from EFI source is my current front runner because of the amount of different options it has available(while more expensive as well $1225), but its plug and play and he can preload a mass array of tunes on it prior to it getting to you so it make startup much easier.
Ive read too many things about the MS stuff having issues. Sure they have a ton of features, small package but the PCMs arent even water tight... says alot about the company (which is a computer company not a automotive performance company). Lots of guys chase there tails tuning just to find out a hardware problem in the PCM causing issues. Again this is just me and my opinion and what ive read just randomly searching.
My plugs were bad, but the iac couldnt control the idle because of the way it was. Also if you don't have the fan relay controller turn off it will mess with the idle
Turn the driver’s side throttle adjustment screw IN (clockwise) half a turn to start with, with that done turn the key on and go to dashboard and find TPS and make sure it reads zero. If not, then shut the key off and wait for the numbers to go black then turn the key on again. Once that reads zero start the vehicle and find IAC Steps on dashboard. This number needs to be within 3-10 at warm idle. If the number reads zero then slowly turn the screw OUT (counter clockwise) until the IAC steps reads between 3-10. If the number is above 10 then shut the vehicle off and turn the screw IN as stated above and repeat the process until the IAC steps are between 3-10.
Turn the driver’s side throttle adjustment screw IN (clockwise) half a turn to start with, with that done turn the key on and go to dashboard and find TPS and make sure it reads zero. If not, then shut the key off and wait for the numbers to go black then turn the key on again. Once that reads zero start the vehicle and find IAC Steps on dashboard. This number needs to be within 3-10 at warm idle. If the number reads zero then slowly turn the screw OUT (counter clockwise) until the IAC steps reads between 3-10. If the number is above 10 then shut the vehicle off and turn the screw IN as stated above and repeat the process until the IAC steps are between 3-10.
Interesting, the throttle screw is on the pass side but either way it seems weird. Stock TPS needs to be adjusted the same way but you have to unplug the TPS and turn the key on for 30s to reset the TPS after adjusting the TB screw. Are you sure you dont have to remove the TPS sensor plug and reset the TPS The same way? Or maybe FItech resets the TPS at every key on which would be ideal.
I was told also that the IAC should be able to compensate for the 2nd fan turn on (AC). Basically that it has enough travel to do so. WHen you think about it the cold start on this motors can be 1000 rpms and settle down to 550 stock so the IAC can control at least 500rpms worth of air.
I was told today that he doesn't speak with people by phone, he only responds via email. And that he lives out of state from FiTech.
Bingo. Hes the one who responded to me when I was initially asking questions via the website contact section. Now I just respond to his email when I need to. Typical reply time is 1-2 days.
So far Kirk has been accurate on everything Ive gotten so far. I wont know about the MAP sensor till I plug it in and set it up. But seeing that I'm entertaining the idea of turbo vs my superharger I might just go with a 3BAR map sensor and call it a day.
My plugs were bad, but the iac couldnt control the idle because of the way it was. Also if you don't have the fan relay controller turn off it will mess with the idle
Side note to your cam idle issue. The cam setting will control the idle airflow settings for different cam profiles. Your cam setting of 2 is considered mild (stock - mild) or a small bump over stock cam specs. You are wayyyy higher than that, I would personally be setting it to cam setting of 3 for yours. You might find that it will come back to idle alittle better.
Side note to your cam idle issue. The cam setting will control the idle airflow settings for different cam profiles. Your cam setting of 2 is considered mild (stock - mild) or a small bump over stock cam specs. You are wayyyy higher than that, I would personally be setting it to cam setting of 3 for yours. You might find that it will come back to idle alittle better.
I thought Kirk would have recommended a higher cam setting too
Yours is a 4.8/5.3 or 5.7? Your heads don't match the smaller 4.8/5.3 so I'm assuming 5.7. I thought your cam specs were in the 230-240 range if I remember correctly so I would bump that up to level 3 cam in the PCM. Get your IAC counts correct at hot idle and see what she does. The issue is large cams are very inefficient at idle/low Rpms so they require less air and fuel than stock like cams. Also the added air if you have cam overlap will fool the 02 into thinking it's leaner than it really is and add to the problem.
Things like throttle blipping cause lots of issues with surge and idle stabilization as the pcm try's to calculate airflow needs for desired rpm when the cam is so large it makes it difficult.
Eh, the cubes will help mellow that cam out. I would still try cam setting 3 and see what it does. For a 5.7 that cam would be considered average to extreme. See attached pic. But I would think the cubes would bring that down to a solid Mild/average cam.
09-05-2017, 08:32 PM
