97 454 L29 Vortec into a 80 K25

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Catbox

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I am the same way.
I just send myself the photos in email.
 

Bextreme04

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Just an update... still waiting for my Chevrolet performance #1 and #5 main bearings to come in.

The big fires here in Oregon caused FedEx to stop delivering for a week due to air quality and now they are waaaaayyyy backed up. They have been in Portland for a week and have just finally made there way here, so hopefully they will be delivered in the next day or two.

I’ve been cleaning parts and prepping them for paint in the meantime, but sadly am lame and don’t have pics. I’ll try and update with pics later tonight if I can get out to the shop tonight.
 

Bextreme04

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Well, didn’t make it out to the shop last night, but here’s some screenshots of the nonsense happening with my FedEx package.
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Catbox

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Some one is having fun scanning the crap out of that package.
 

Bextreme04

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Some one is having fun scanning the crap out of that package.

Yeah, I think most of the "In Transit" ones are automated to go out every 12 hours if there isn't an actual new scan. Its quite the ridiculous situation... 8 days to go from troutdale to salem and still not out on a truck for delivery yet
 

Bextreme04

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Well, bitching about Fedex must have been the magic charm... its now suddenly showing as on the truck and out for delivery! Hopefully I can make some progress on putting the engine together tonight!
 

Markmx6

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The biggest issue is definitely tuning. I was originally planning on using the 2156 Express Van OS and doing my own modifications using TunerPro. Then, I ended up remembering that I had a buddy that built an 8.1L and didn't use the factory EFI system. When I talked to him, it turned out he still had the entire factory 8.1L truck coil set and wiring harnesses sitting in his garage and he was happy to send them to me to get rid of them. So then I decided to run the 7.4 as a CNP setup with a 24x reluctor.

Unfortunately that means I need to do some more surgery on the OS. Currently I'm hoping to start with a 2002 12212156 Silverado 6.0L manual trans 4x4 OS(I couldn't find a 6.0/4L80e/4x4 2156) and segment swap the Express van 4L80E trans segments in. Alternatively I can start with the express van OS and copy in the 6.0L engine segment. Then I have to copy all the 8.1L engine calibration tables values over from a different OS, since they never had an 8.1 in the 2156 OS.

I'm using the OBDX Pro Vt tool, PCM Hammer, and TunerPro RT for all of this, so other than buying the programming tool for $69... it's all free. We'll see if the amount of time spent on using the opensource tools makes up the difference in cost from just using HPTuners or EFI Live.

The other nice thing with this setup is that it will be fully OBD2 and customizable, so I can use the same tool to datalog, tune and send data to a tablet or my phone so I can monitor everything I need to while driving without needing to install extra gauges.

On my 99 Suburban with the 454 I also ran the CNP setup with the 0411. You can buy the reluctor wheel for around $40 because it is the same one the L21 454 uses. If I can find a link I'll post where I got mine from, just make sure to get the crank sensor with it. EFI Connection has them, but at a lot higher price. I did buy their distributor cover though...

I also have a pretty good base tune, but it is an HPTuners file. I could flash your PCM or flash one of the ones I have lying around if you pay the $100 license fee and shipping. Then you could continue tuning with your own software... If you have a way of using the file I have then I would just email it to you. Mine started out as a 4.8 liter tune (I already had a licensed copy) and then made the needed changes.

Found a link for the reluctor wheel
http://oemcats.com/oem-parts/12552480.html
 
Last edited:

Markmx6

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Also I would make sure you budget for headers or manifolds for your exhaust. The square body frame rails are 30 inches wide and the OBS is 40 inches wide. That bit me because I wasn't anticipating it when I put a 91 TBI 454 in an 85 C10 that had a 350...
 

Bextreme04

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On my 99 Suburban with the 454 I also ran the CNP setup with the 0411. You can buy the reluctor wheel for around $40 because it is the same one the L21 454 uses. If I can find a link I'll post where I got mine from, just make sure to get the crank sensor with it. EFI Connection has them, but at a lot higher price. I did buy their distributor cover though...

I also have a pretty good base tune, but it is an HPTuners file. I could flash your PCM or flash one of the ones I have lying around if you pay the $100 license fee and shipping. Then you could continue tuning with your own software... If you have a way of using the file I have then I would just email it to you. Mine started out as a 4.8 liter tune (I already had a licensed copy) and then made the needed changes.

Found a link for the reluctor wheel
http://oemcats.com/oem-parts/12552480.html

I had to get the EFI connection reluctor... the factory L21 reluctor is discontinued and no longer available from anywhere. That OEMcats link and several others are just sites that order from GM. It looks like they are in stock, but when you go to order it they cancel the order a few days later. It sucks, because it only cost about $20 from GM before they discontinued it.

What did you do to mount the coils? Did you just get L21 valve covers? I'm using the factory D581 coils and harness from a buddies 8.1L. Do the 8.1L valve covers fit?

I already have a set of headers for it.
 

Markmx6

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That sucks about the reluctor, I must have been lucky, but it was about 2 years ago...

I didn't have my 8.1 at the time so I didn't have it to use as a reference. I just mounted the coils to the factory vortec valve covers. I made some standoffs using some bolts. I ran the bolts from inside the valve cover facing out and then Threadlocked a... (its a nut, but it is what is used to join two pieces of all thread I'm not sure what it's called) then mounted the coils and used another nut to hold them down. You have to be careful as to where you put the holes because there is not a lot of clearance and I destroyed a set of covers because the bolt head was hitting the rocker arm on the first set.

I used the round coils because, well they were cheap and I had bought them for another project (I was going to convert my 98 5.7 to CNP, but this was a better use)

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Bextreme04

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That sucks about the reluctor, I must have been lucky, but it was about 2 years ago...

I didn't have my 8.1 at the time so I didn't have it to use as a reference. I just mounted the coils to the factory vortec valve covers. I made some standoffs using some bolts. I ran the bolts from inside the valve cover facing out and then Threadlocked a... (its a nut, but it is what is used to join two pieces of all thread I'm not sure what it's called) then mounted the coils and used another nut to hold them down. You have to be careful as to where you put the holes because there is not a lot of clearance and I destroyed a set of covers because the bolt head was hitting the rocker arm on the first set.

I used the round coils because, well they were cheap and I had bought them for another project (I was going to convert my 98 5.7 to CNP, but this was a better use)

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That looks pretty good! The relocation brackets are pretty cheap so I guess I'll either buy a set or try to make my own brackets. The L21 valve covers have the individual mounting points welded on already, just like the 8.1L does.. except the L21 covers have the passenger side skewed to clear the throttle body.

How long have you been running yours? How do you like it? What kind of mileage and power have you been getting out of it?
 

Bextreme04

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They made it finally!!! Time to get the bottom end put together tonight hopefully and then get the pistons in and deck clearance measured.
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TubeTruck

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:popcorn:

Have you made any progress on this? Or is it in another thread? I wanted to drop my 4L80e in over the winter but the cost of converting the 350 to use a reluctor and TPS (plus cam and rebuild kit) I may as well rebuild the EFI 454. So that's my new plan. Mine is an L29 out of a '98 Suburban and I have an 0411 PCM from my 2001 Silverado that had a 6.0/4L80e so I should be golden there. I bought EFI Live about 5 years ago but haven't had a lot of practice with it. I'm trying to learn about upgrading the OS and all that fun stuff. Also looking into switching to COP so please add as many details and part numbers as possible. I'm going to try and spend the winter rebuilding the motor and transmission since it has 259k miles and has never been rebuilt and building the harness.
 

Bextreme04

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K25
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350-4bbl
:popcorn:

Have you made any progress on this? Or is it in another thread? I wanted to drop my 4L80e in over the winter but the cost of converting the 350 to use a reluctor and TPS (plus cam and rebuild kit) I may as well rebuild the EFI 454. So that's my new plan. Mine is an L29 out of a '98 Suburban and I have an 0411 PCM from my 2001 Silverado that had a 6.0/4L80e so I should be golden there. I bought EFI Live about 5 years ago but haven't had a lot of practice with it. I'm trying to learn about upgrading the OS and all that fun stuff. Also looking into switching to COP so please add as many details and part numbers as possible. I'm going to try and spend the winter rebuilding the motor and transmission since it has 259k miles and has never been rebuilt and building the harness.

It's been slowed a bit with the fires and Rona stuff going on. My wife and I also just opened up a business and I've only been able to get out to the shop for an hour every now and then. I got the crank, rear main seal, and oil pump installed. I've also got the crank gear and EFI Connection 24x reluctor wheel. Then I got half of the pistons installed before stalling out with the in-laws coming into town for thanksgiving. I'm hoping to take advantage of the 4-day weekend over thanksgiving to finish stabbing the pistons and get my deck clearance measured. Then I need to set the camshaft and degree it in to make sure all of that is right and get the timing set on and the cover installed.

If I have time after that, I need to finish port matching the intake and heads and then clean and paint everything. I'll get some pics up of where I am now and some of the parts. I got the distributor rebuilt also and bought a set of coil packs, ignition harness, and mounting brackets from a 5.3L for $20 locally.
 

Markmx6

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Mark
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C3500 dually
Engine Size
454
:popcorn:

Have you made any progress on this? Or is it in another thread? I wanted to drop my 4L80e in over the winter but the cost of converting the 350 to use a reluctor and TPS (plus cam and rebuild kit) I may as well rebuild the EFI 454. So that's my new plan. Mine is an L29 out of a '98 Suburban and I have an 0411 PCM from my 2001 Silverado that had a 6.0/4L80e so I should be golden there. I bought EFI Live about 5 years ago but haven't had a lot of practice with it. I'm trying to learn about upgrading the OS and all that fun stuff. Also looking into switching to COP so please add as many details and part numbers as possible. I'm going to try and spend the winter rebuilding the motor and transmission since it has 259k miles and has never been rebuilt and building the harness.

http://www.gmtruckcentral.com/articles/24x.html

This has some useful information for you. I read through this several times before I started cutting wires
 

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