12200411 PCM swap for 1996 to 2000 GMT400 trucks

[PlayingWithTBI]

I'm a little curious how friendly tuner pro is, any screenshots?

Here's some from 7747 bin with $42 mask just to give you an idea;

You must be registered for see images attach

You must be registered for see images attach

Lots of good commentary too

You must be registered for see images attach

More info:

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?3256-Tuner-Pro-FAQ-and-Tutorials

https://www.tunerpro.net/

 

[Christian Steffen]

Here's some from 7747 bin with $42 mask just to give you an idea;

You must be registered for see images attach

You must be registered for see images attach

Lots of good commentary too

You must be registered for see images attach

More info:

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?3256-Tuner-Pro-FAQ-and-Tutorials

https://www.tunerpro.net/

For that kind of money I would certainly give it a try if I didn't already have hp tuners. It doesn't look quite a friendly, but for <$100 vs $600 i would try it lol

 

[John Cunningham]

Hey Christian here is a question that you may know or not know but I will give it a shot.

I have the 0411 pcm and even purchased the correct holder for it. I have read the EFI connection book as well.

I am aware that I have the 512kb pcm and that is has the all the information that lextech gave me for my truck.....perfect.

Having said that I am building a 496 for this truck and wanted to prep it for the COP modification at a later date which simply means I must add the 24x timer behind the timing cover during the build. I would remove the 4x and replace it with the 24x piece so can use COP.

Since the same 0411 can use either the 4x or 24x can I install the 24x now in preparation at a later date and still use my normal dist and wires etc as it stands not............or?

If I add the 24x do you HAVE TO use the cop at this time.

One of the issues is 8.1 Valve covers do not work as they are too shallow. As you know the valve train is deeper in the casting thereby a thinner cover was used.

There is only 1 ..thats one valve cover assembly that will work. It has to be from the
L21 454 found in the larger cab chassis trucks like the top kick etc. They had COP and not the normal L29 pickups that gmt400 trucks have. For some reason the larger trucks from 1998 thru 2000 used the L21 COP.

These valve covers I cannot seem to locate. Maybe you know of a source.

My main question is could I use the 24x wheel right now and use the rest of the ignition system?

Thanks John

 

[Christian Steffen]

Hey Christian here is a question that you may know or not know but I will give it a shot.

I have the 0411 pcm and even purchased the correct holder for it. I have read the EFI connection book as well.

I am aware that I have the 512kb pcm and that is has the all the information that lextech gave me for my truck.....perfect.

Having said that I am building a 496 for this truck and wanted to prep it for the COP modification at a later date which simply means I must add the 24x timer behind the timing cover during the build. I would remove the 4x and replace it with the 24x piece so can use COP.

Since the same 0411 can use either the 4x or 24x can I install the 24x now in preparation at a later date and still use my normal dist and wires etc as it stands not............or?

If I add the 24x do you HAVE TO use the cop at this time.

One of the issues is 8.1 Valve covers do not work as they are too shallow. As you know the valve train is deeper in the casting thereby a thinner cover was used.

There is only 1 ..thats one valve cover assembly that will work. It has to be from the
L21 454 found in the larger cab chassis trucks like the top kick etc. They had COP and not the normal L29 pickups that gmt400 trucks have. For some reason the larger trucks from 1998 thru 2000 used the L21 COP.

These valve covers I cannot seem to locate. Maybe you know of a source.

My main question is could I use the 24x wheel right now and use the rest of the ignition system?

Thanks John

I have not personally done this swap or really looked into it, so someone please correct me if I'm wrong here.

As far as I know you will not be able to run the 24x reluctor without going all the way to 24x. The computer will still pick up all those reluctor teeth.

I don't have any foos spots to get a set of those valve covers. Check salvage yards ? Perhaps build a set of brackers? I believe @PolarBear made some for his 24x sbc.

 

[John Cunningham]

I have not personally done this swap or really looked into it, so someone please correct me if I'm wrong here.

As far as I know you will not be able to run the 24x reluctor without going all the way to 24x. The computer will still pick up all those reluctor teeth.

I don't have any foos spots to get a set of those valve covers. Check salvage yards ? Perhaps build a set of brackers? I believe @PolarBear made some for his 24x sbc.

Lextech wrote back and said once you install the 24x you have to complete the cop conversion..I want it to look factory so unless I find those covers I wont do it.
I not sure that they give that much improvement with a low compression low rpm engine..the only reason to complete the 0411 swap is not having to rely on somebody to send my box back and forth etc..Christian was was the noticeable change that you saw during your conversion to the 0411 pcm?

 

[Christian Steffen]

Lextech wrote back and said once you install the 24x you have to complete the cop conversion..I want it to look factory so unless I find those covers I wont do it.
I not sure that they give that much improvement with a low compression low rpm engine..the only reason to complete the 0411 swap is not having to rely on somebody to send my box back and forth etc..Christian was was the noticeable change that you saw during your conversion to the 0411 pcm?

Well I went from a mail order tuned black box to self tuned 0411.. so yes there were a lot of changes that are noticeable. I have tuned a truck with the black box since and a couple others with 0411s and the tuning goes better with the 0411. There is a lot more that you can do with this computer. If you're already having custom tuning done (which you are) then imo its a no brainer to go 0411.

 

[L31MaxExpress]

Well I went from a mail order tuned black box to self tuned 0411.. so yes there were a lot of changes that are noticeable. I have tuned a truck with the black box since and a couple others with 0411s and the tuning goes better with the 0411. There is a lot more that you can do with this computer. If you're already having custom tuning done (which you are) then imo its a no brainer to go 0411.

I can do as much in the Black Box as the 0411 however the 0411 is still a vastly superior PCM and has much better code running it.
Black Box PCMs have been reversed alot more by TunerCats than HP. TunerCats has many more options you can alter in the tuning.

 

[PolarBear]

I can do as much in the Black Box as the 0411 however the 0411 is still a vastly superior PCM and has much better code running it.
Black Box PCMs have been reversed alot more by TunerCats than HP. TunerCats has many more options you can alter in the tuning.

Lol... just lol...

Well I went from a mail order tuned black box to self tuned 0411.. so yes there were a lot of changes that are noticeable. I have tuned a truck with the black box since and a couple others with 0411s and the tuning goes better with the 0411. There is a lot more that you can do with this computer. If you're already having custom tuning done (which you are) then imo its a no brainer to go 0411.

John, Jeff (Lextech) is totally right. Once you remove the 4x wheel. You're totally committed to COP ignition.

For the coil packs, I bought some ICT Billet coil relocation brackets and welded them to a set of aluminum valvecovers.

As far as I know, I'm one of a handful guys who have successfully finished the 24x COP conversion and tuned it correctly to where it's a fully functioning vehicle.

Here are some pictures of my coil bracket setup.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Also, here are some 24x videos I made. As it seems theres very little accurate documentation available.

xc_hide_links_from_guests_guests_error_hide_media

xc_hide_links_from_guests_guests_error_hide_media

 

[eshaw]

PolarBear thanks for making this post! Lots of good information here. I've been exploring this information for my truck as well but it will be a long while before I get to it. How long have you been using HP Tuners and how do you like it??? Have you ever used EFI Live and if you have how do the two compare? One other question. What all is involved in making the swap over to E85 use?

 

[Christian Steffen]

Lol... just lol...



John, Jeff (Lextech) is totally right. Once you remove the 4x wheel. You're totally committed to COP ignition.

For the coil packs, I bought some ICT Billet coil relocation brackets and welded them to a set of aluminum valvecovers.

As far as I know, I'm one of a handful guys who have successfully finished the 24x COP conversion and tuned it correctly to where it's a fully functioning vehicle.

I really like how your project turned out, definitely unique. I did find a guy on hp tuners/ls1tech forum that converted a mark IV 454 to 24x using an 0411, was another fun project to watch.