E85 500 HP 383 with a L31 truck intake

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Supercharged111

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Yep...GMT800s had the 5.7L vortec in Mexico and Brazil up until 06 or so.

Isuzu box truck had the 5.7 until 03 or 04 here too. The 03 I saw was Blue/Green as well.

Can you post a stock tune for that? This has had my curiosity for some time now. On second though, are there any custom operating systems for that PCM out there?
 

Bloke

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So its not like i can slap this pcm on my truck and try to get a custom tune on it? I only got 138k on the engine. I would like to replace the engine for something other than stock. I can go the 383 route and spend $5k plus on it or find a crate 350/5.7 thats turnkey or rebuild it hopefully for less and come out with close to 300 hp hopefully. I wonder if i rebuild it can i just use the PN that are used on the 383?
 

stutaeng

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Hey guys not hijack this thread, but what is involved in swapping a 4.3 to 5.7 Vortec in a GMT 800? Is it really just adding 2 additional injector wiring? 4.3 is a 1500 2wd.

My computer says 09360605 and has a white and black plug. I thought I had the 0411 ECU, but apparently not?

5.7 would be from my running '00 k3500. Also planning on 4l80 during swap. Looks like some repining is involved, but doesn't seem too bad. Currently looking for 2wd 4l80.
 

Bloke

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Is this PCM better than my own stock PCM in the sense that it has more upgradeable options in it to modify? I have a superchips tune on it and not a custom one. Maybe I should retune my own with a custom tune if anyone still does them to this year truck. I will look into this.

Mind you I wont do this myself. I have neither the time or patience to do these mods. Most I will do is brakes, hoses, belts 7 sparkplugs cause I hate the 8th one by the starter. Fudge that.

I live on the border I would hit a junkyard but in Mexico but that's dangerous since you don't know who owns them and one can find stolen US cars in there at any given time.

I have another stock PCM already with my VIN on it. I have this as a backup due to hypertech not fully writing to the PCM back in 2003. So in the 3rd try and 3rd tow to dealership I went and got another and reflashed for 100 bucks so I wouldn't be with a vehicle while I sent my original back to hypertech to figure out the issue. It would write fully to the pcm over there but it would always stop at 75% when it was on my vehicle. after the 5th try I just went to superchips.
 
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df2x4

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Is this PCM better than my own stock PCM in the sense that it has more upgradeable options in it to modify? I have a superchips tune on it and not a custom one. Maybe I should retune my own with a custom tune if anyone still does them to this year truck. I will look into this.

Mind you I wont do this myself. I have neither the time or patience to do these mods. Most I will do is brakes, hoses, belts 7 sparkplugs cause I hate the 8th one by the starter. Fudge that.

I live on the border I would hit a junkyard but in Mexico but that's dangerous since you don't know who owns them and one can find stolen US cars in there at any given time.

I have another stock PCM already with my VIN on it. I have this as a backup due to hypertech not fully writing to the PCM back in 2003. So in the 3rd try and 3rd tow to dealership I went and got another and reflashed for 100 bucks so I wouldn't be with a vehicle while I sent my original back to hypertech to figure out the issue. It would write fully to the pcm over there but it would always stop at 75% when it was on my vehicle. after the 5th try I just went to superchips.

Good lord... I don't know why anyone messes with those handheld programmers. What a mess.

People do still tune the stock PCMs in the '96+ trucks. Black Bear Performance tuned my red '97. Seeing as you have a '98 though, your stock PCM is actually supported by HPTuners so any local tuner who uses that program should be able to do it.
 

Supercharged111

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Good lord... I don't know why anyone messes with those handheld programmers. What a mess.

People do still tune the stock PCMs in the '96+ trucks. Black Bear Performance tuned my red '97. Seeing as you have a '98 though, your stock PCM is actually supported by HPTuners so any local tuner who uses that program should be able to do it.

98+ is also supported by EFILive. I thought HPT did 96-97 too?
 
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