PCM Options for Supercharged 454 / 4L80E

[dave w]

Here is what I'm thinking for a $85 2 BAR Conversion, see pic below. Currently the engine idles at about 40 Kpa. All feedback welcome!

dave w

[EagleMark]

Nice find, Mark. I've got similar data squirreled away here because I can never find it on the 'net when I need it.

Problem with the internet is when you go back the website and information is gone... when I find good stuff I save it all in a folder... but for now the chart he needed is here with a link...

Here is what I'm thinking for a $85 2 BAR Conversion, see pic below. Currently the engine idles at about 40 Kpa. All feedback welcome!

dave w

You and 1project2many seem to have your heads wrapped around this... other feedback is, did you ever get the adx I worked on, working? Gotta have data to do this. Don't think Datamaster does boost and I know it can't be custimized! Was it fianlly hooking up right and no glitch? Then some values are going to need to be changed to match 2 bar! In doing the TunerPro Look Up I found a few turbo and supercahrged adx files... Probably going to want to watch closely knock and if your lucky $85 adx may have retard. I changed the knock history table in my LT1 to spit out retard instead of knock counts and it gives me exact figure in cell to reduce.

[1project2many]

Dave, you've got the right idea with the chart for the two tables. The MAP voltage values in the table won't change, so the pressure they represent has to be adjusted. As long as you have a way to keep track of what your tuning you're good. I would probably get the definition file and ADX set up to show the correct values just to prevent a silly mistake but that may be because I've had more years to demonstrate to myself that I can actually make them. :) (I once accidentally set up a cal to enable lean cruise when in boost! I didn't hurt anything but it took a real effort to figure out why AFR was going leaner when the VE and PE tables were all set up for richer operation. )


Datamaster for $58 has checkboxes for OE 2 BAR cal or aftermarket 3 BAR cal. I wish it were more user configurable though. For $58 with DIS it doesn't display spark advance correctly. The displayed timing gets lower as spark advance increases! In order to get the correct values I have to subtract the reference angle from the displayed timing values. The result, without the sign, is the actual timing.

[dave w]

I seem to be having trouble with my digital camera. I've resorted to my cell camera.

dave w

[dave w]

Problem with the internet is when you go back the website and information is gone... when I find good stuff I save it all in a folder... but for now the chart he needed is here with a link...

You and 1project2many seem to have your heads wrapped around this... other feedback is, did you ever get the adx I worked on, working? Gotta have data to do this. Don't think Datamaster does boost and I know it can't be custimized! Was it fianlly hooking up right and no glitch? Then some values are going to need to be changed to match 2 bar! In doing the TunerPro Look Up I found a few turbo and supercahrged adx files... Probably going to want to watch closely knock and if your lucky $85 adx may have retard. I changed the knock history table in my LT1 to spit out retard instead of knock counts and it gives me exact figure in cell to reduce.

I posted some pics. I am using a TunerPro .xdf, and data logging with DataMaster TTS. As many of you know, I tune for hire. This is a tune I am hired to do, so the final decision to convert to 2 BAR is not mine. At this point, I don't know if the owner will decide to go 2 BAR or not? If every "Truck Magazine" had 2 BAR conversions articles for superchargers, then I'm sure the owner would buy into the idea. I'm thinking the owner will not want to "Guinea Pig" what must seem like a wild idea to someone who does not even have an email address? The vehicle owner uses the Dually to tow "Toys" to some remote areas. I'm thinking the vehicle owner wants any available "Scan Tool Technician" to be able to help, should a problem occur. I'm always willing to share the information from a tune, unless otherwise requested not to.

dave w

[1project2many]

Dave, I can understand your situation. Many good technicians won't want to get involved with that engine as soon as they see the S/C installed, and rightly so. No one wants to be held responsible when a good fix is made bad by incomplete, improper, or badly implemented prior work. And when it comes to custom tuning, I'm sure you're well aware that everything down to faulty brake light bulbs and bad music on the radio will be blamed on the computer and the tune once you make a single change. I've been there myself plenty of times. If I were trying to sell the MAP conversion I would sell it by comparing it to adding a set of high quality aftermarket gauges to a truck with factory gauges. The factory gauges are still there, but they're just not as accurate as the ones you're putting in. If he goes for the swap I'd make a simple 3 column chart to include for anyone using a traditional scan tool: "If your scantool show this kPa, or this MAP voltage, the real MAP is this." All other scantool readings will look normal. I'd give the guy a few copies of my card and I'd probably tape one to the ecm and another to the hood so tech support is available in case he's broken down. And I'd probably point out that he's already been a guinea pig by installing an aftermarket part on a computer controlled engine which is not understood by the computer. Again, that's if I felt making the sale was worth the effort.

Good luck.

[EagleMark]

Plus it's an OEM part used on factory turbo and supercharger applications! It looks the same and will mount the same and plug in the same...

I'm curious what the manufacturer of the Supercharger says about tune after installation?

[dave w]

Plus it's an OEM part used on factory turbo and supercharger applications! It looks the same and will mount the same and plug in the same...

I'm curious what the manufacturer of the Supercharger says about tune after installation?

NOTHING about tuning!

The Supercharger Manufacture recommends more fuel, recommending fuel pump upgrade and adding an adjustable fuel pressure regulator!

dave w

[1project2many]

NOTHING about tuning!

The Supercharger Manufacture recommends more fuel, recommending fuel pump upgrade and adding an adjustable fuel pressure regulator!

dave w

I've been through something similar. The customer did a no-no and improved the airflow of a stock 8.2 by changing cam and having head work done before adding the S/C. S/C maker refused to give any help... S/C system is designed for stock engine period. I asked for injector flow... "Proprietary." Silly... numbers were on outside of injector. I also asked about mfgr adjusting separate controller PW for fuel based on dyno readings. "Nope." I even threatened to pull the controller apart and make changes myself. "It's encoded and you can't read it." I didn't buy that story but it was ultimately the customer's decision and he didn't want to upset the S/C maker. About a month later he called to tell me he'd burnt a valve and was replacing the non-stock components with stockers. All because one company didn't want to play ball.

Loosing about 1/3 of the VE / Timing table for boost will only hurt overall drive ability.

For this application you would likely be ok. The weight of the vehicle and relatively slow changes in speed won't require high resolution tables to correct for transients. It is possible to rewrite the VE and fuel tables to make up for some lost resolution.

The 2 BAR calibration conversion without XDF and ADX file modification should be a 2 hr job. Changing the MAP sensor and modifying the connector probably won't require an hour's labor. Additional tuning cost depends on how much time is required.

[dave w]

Dave, I can understand your situation. Many good technicians won't want to get involved with that engine as soon as they see the S/C installed, and rightly so. No one wants to be held responsible when a good fix is made bad by incomplete, improper, or badly implemented prior work. And when it comes to custom tuning, I'm sure you're well aware that everything down to faulty brake light bulbs and bad music on the radio will be blamed on the computer and the tune once you make a single change. I've been there myself plenty of times. If I were trying to sell the MAP conversion I would sell it by comparing it to adding a set of high quality aftermarket gauges to a truck with factory gauges. The factory gauges are still there, but they're just not as accurate as the ones you're putting in. If he goes for the swap I'd make a simple 3 column chart to include for anyone using a traditional scan tool: "If your scantool show this kPa, or this MAP voltage, the real MAP is this." All other scantool readings will look normal. I'd give the guy a few copies of my card and I'd probably tape one to the ecm and another to the hood so tech support is available in case he's broken down. And I'd probably point out that he's already been a guinea pig by installing an aftermarket part on a computer controlled engine which is not understood by the computer. Again, that's if I felt making the sale was worth the effort.

Good luck.

The technical information exchange about converting the Supercharger to a 2 BAR MAP is good stuff. I'm in hopes others find the exchange of information on a 2 BAR MAP conversion useful. I really appreciate the input 1project2many!

I'm not going to get rich by selling and servicing EFI Systems, but it helps support my "Toy" addiction. I sure can't quit my "day job" on the few sales I get each month. Ultimately, I'd like the vehicle owner to have a good tune. Seems the best option available for a good tune is a 2 BAR MAP conversion.

dave w

[JeepsAndGuns]

Not to hijack the thread, but as always, I want to learn a little here. I understand what a 2bar map sensor is.
From what I am reading, swapping to a 2bar map sensor is about the only real hard part that needs changed when going to forced industion? Since the 2 bar has the same output signal (if I am reading this thread correctly) then the only real mod to the code or tune would be whatever is needed for the fuel and spark parameters? I was thinking there was a lot more to it than that. I thought you had to use a forced induction specific ecm/pcm, and a forced induction specific cal/bin.
So again unless I am misunderstanding it, all thats really needed is to edit the XDF to display the correct map numbers in place of the old numbers?
I'm still a noob and still learning.
I have had a few dreams of installing two small turbos on my engine, one on each header. (where the little smiley that sets there and drools...lol)

[dave w]

Not to hijack the thread, but as always, I want to learn a little here. I understand what a 2bar map sensor is.
From what I am reading, swapping to a 2bar map sensor is about the only real hard part that needs changed when going to forced industion? Since the 2 bar has the same output signal (if I am reading this thread correctly) then the only real mod to the code or tune would be whatever is needed for the fuel and spark parameters? I was thinking there was a lot more to it than that. I thought you had to use a forced induction specific ecm/pcm, and a forced induction specific cal/bin.
So again unless I am misunderstanding it, all thats really needed is to edit the XDF to display the correct map numbers in place of the old numbers?
I'm still a noob and still learning.
I have had a few dreams of installing two small turbos on my engine, one on each header. (where the little smiley that sets there and drools...lol)

The original thinking of this thread was to install forced induction specific ECM / PCM. Possibly the "Best Option" is to upgrade ECM / PCM. The idea / option of converting the current PCM to use 2 BAR was an excellent idea from 1project2many! Like mention earlier, all vacuum / Kpa parameters will need to be re-calibrated to a 2 BAR scale. Ultimately, converting the PCM to use a 2 BAR MAP has trade-offs in drive ability. I personally would like a VE / Timing table extension for the Boost and still use all the original VE / Timing table for natural aspiration!! Loosing about 1/3 of the VE / Timing table for boost will only hurt overall drive ability.

dave w

[TravisMartin]

I'm always willing to share the information from a tune, unless otherwise requested not to.

dave w

How did this turn out? I'm brand new here, and to EFI mods, and have a project underway that would benefit from your experience. I'm putting a '95 TBI 454/4L80E into my '78 C10 shorty. I'm confident I can handle the hardware and wiring end, but not so much on tuning. I'll start with the stock '95 tune to sort out the conversion, but I have a Whipple kit waiting in the wings that I'd like to add to the mix, so I could sure use some pointers. How did the customer's dually turn out?

Thanks!

Travis

[dave w]

How did this turn out? I'm brand new here, and to EFI mods, and have a project underway that would benefit from your experience. I'm putting a '95 TBI 454/4L80E into my '78 C10 shorty. I'm confident I can handle the hardware and wiring end, but not so much on tuning. I'll start with the stock '95 tune to sort out the conversion, but I have a Whipple kit waiting in the wings that I'd like to add to the mix, so I could sure use some pointers. How did the customer's dually turn out?

Thanks!

Travis

The Dually owner only contacted me once after accepting delivery, he was selling the Dually without the supercharger and wanted a stock chip.

Hindsight being 20/20, I would recommend using a Dynamic EFI system for boost: http://www.dynamicefi.com/EBL_Choice.php

dave w

[dave w]

Here is what I'm thinking for a $85 2 BAR Conversion, see pic below. Currently the engine idles at about 40 Kpa. All feedback welcome!

dave w

I have revised my thinking on the chart posted in the above tread. The supercharger is rated for 6 psi boost, so I'm thinking the 2 BAR MAP will not show 5 VDC at 6 psi boost. I'm thinking the 6 PSI boost will have a maximum voltage of about 3.4 ~ 3.6 VDC from a 2 BAR MAP sensor. That's not really a good range of voltage for tuning from 20 Kpa to about 140 Kpa.

dave w