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Engine swapping a 454 Vortec and keeping the factory TBI

If you look at where hp/tq numbers went on the change from port fuel injection to direct injection on the other v-8's, 6's and 4 bangers its going to be better.

Just need to see the hp/tq curves.
 
Just posting a long overdue follow up on this. After pulling the intake manifold on this, three out of the four intake valves on the drivers side were bent. One was actually bent, broken and completely out of place. I do wonder what would cause this. The best theory I have at the moment is that the pushrods were just undersized. They are the 5/16 version, There are 3/8 and 7/16 versions out there and this one is upgradeable. Or maybe it was a bad adjustment or it got overworked. I don't know but it was an oily mess as it needed a good regasketing anyway. I'll post pics as the parts come in and it goes back together.
 
CUCV2 said:
Just posting a long overdue follow up on this. After pulling the intake manifold on this, three out of the four intake valves on the drivers side were bent. One was actually bent, broken and completely out of place. I do wonder what would cause this. The best theory I have at the moment is that the pushrods were just undersized. They are the 5/16 version, There are 3/8 and 7/16 versions out there and this one is upgradeable. Or maybe it was a bad adjustment or it got overworked. I don't know but it was an oily mess as it needed a good regasketing anyway. I'll post pics as the parts come in and it goes back together.
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It happened to me from overworking it
 
I think GM is putting the r/d money into the electric side of things. That new Hummer is the wave of the future. I won't be riding that wave, unfortunately it's a little too pricey for me, but I think the gas and diesel R&D money is gone. There are a bunch of companies trying to be the first to get an electric pickup that will actually go more than 500 miles on a charge and not burn through the batteries when towing.
To get back to the topic, though, why are the exhaust ports smaller on the Vortec and the 8.1 than on the older 7.4? I thought free flowing was the goal...that visual is great having all three together. Would the 7.4 heads in the photo be from a gen VI engine? I've got a 96 block but does not have vortec heads, so I'm thinking those are probably the heads I have.
If you need accessory brackets for a serpentine setup on the metric block, let me know, I might have some that work. But it sounds like you're not doing the swap now...way less trouble that's for sure.
By the way, those are some of the cleanest engine compartments I've ever seen. Truly impressive, I wish I had the ability to make things look so clean and neat. Spark plug wires all perfect, even Sambo is looking right at the camera.
 
anwat said:
I think GM is putting the r/d money into the electric side of things. That new Hummer is the wave of the future. I won't be riding that wave, unfortunately it's a little too pricey for me, but I think the gas and diesel R&D money is gone. There are a bunch of companies trying to be the first to get an electric pickup that will actually go more than 500 miles on a charge and not burn through the batteries when towing.
To get back to the topic, though, why are the exhaust ports smaller on the Vortec and the 8.1 than on the older 7.4? I thought free flowing was the goal...that visual is great having all three together. Would the 7.4 heads in the photo be from a gen VI engine? I've got a 96 block but does not have vortec heads, so I'm thinking those are probably the heads I have.
If you need accessory brackets for a serpentine setup on the metric block, let me know, I might have some that work. But it sounds like you're not doing the swap now...way less trouble that's for sure.
By the way, those are some of the cleanest engine compartments I've ever seen. Truly impressive, I wish I had the ability to make things look so clean and neat. Spark plug wires all perfect, even Sambo is looking right at the camera.
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Thanks for the insight. I think you may have been looking at Larry’s post. He does super nice work and definitely is an inspiration to make a clean engine bay. But this engine bay is not in the same league and the Qs you’re asking would be better answered by him. That said, I actually have been cleaning up the 454s engine bay today as well as replacing an ebrake cable that turned into a minor brake restoration.

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CUCV2 said:
Did you put bigger pushrods back in?
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No just stock size.
I was towing hard up the grape vine full throttle for about 6 miles, the engine didn't like it.
It wasn't a bbc, but a 360 dodge.
I bent no 1 exhaust and intake. That ended up bending one valve.
Fixed all and it was fine
 
That’s my mistake. I meant to load two videos of the engine turning over. The first one shows the rocker where the broken pushrod was and it has a catch in the rocking motion. Turns out the washer under the rocker nut is in upside down so the rounded side is where the flat side should be. The second video shows it correct and working correctly. It’s all back together and starts after a after replacing a defective distributor as well. It only stays running for a few seconds and won’t idle though. I think the TBI unit needs a rebuild. Currently debating whether to rebuild this one, just get a remanned unit, or get a performance unit. The budget is tight so it will probably get a rebuild.
 
I could be thinking of something else, but I seem to remember something about the electrical side of TBI that let's the engine start but without the continued signal it just dies after a few seconds?
 
Justin V said:
I could be thinking of something else, but I seem to remember something about the electrical side of TBI that let's the engine start but without the continued signal it just dies after a few seconds?
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One of the fuel injectors keeps pumping fuel after it stalls as well. I know next to nothing about TBI but would definitely like to be chasing the right carrot here. Any help is appreciated.
 
Well the continued release of fuel is definitely a problem, might have more than one problem here...
 
Justin V said:
Well the continued release of fuel is definitely a problem, might have more than one problem here...
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I was planning on replacing the injectors and the idle air control sensor in the rebuild if that is the way forward.

It's amazing that there are so many issues with getting this running but for the brief period it runs, it does sound way better than it used to.
 
I would try to figure out what was wrong with the unit you have on there before you replace it. It sounds like it runs ok when you start it, is that right? What happens when it dies out, does it sputter, rpms drop, does it surge back and forth, what leads it to the stall? Rich or lean? I would agree that it sounds electrical if one injector keeps running after the stall. That's not something that is going to be fixed by getting a rebuilt tbi unit. Do you have the ALDL port hooked up on this? Running that while it starts and runs might give you the clues you need to diagnose what's going on.
 
anwat said:
I would try to figure out what was wrong with the unit you have on there before you replace it. It sounds like it runs ok when you start it, is that right? What happens when it dies out, does it sputter, rpms drop, does it surge back and forth, what leads it to the stall? Rich or lean? I would agree that it sounds electrical if one injector keeps running after the stall. That's not something that is going to be fixed by getting a rebuilt tbi unit. Do you have the ALDL port hooked up on this? Running that while it starts and runs might give you the clues you need to diagnose what's going on.
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It starts ok and even idles for about half a second then sputters out. If you continuously jab the gas pedal, it will stay running, albeit not well.

There is a port to check codes but I have never used it. I think I tried to borrow one from an auto parts store to check it but they didn't have a plug that old. What exactly is an ALDL?
 
CUCV2 said:
One of the fuel injectors keeps pumping fuel after it stalls as well. I know next to nothing about TBI but would definitely like to be chasing the right carrot here. Any help is appreciated.
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I assume it sprays until it loses pressure?

IIRC the injector wires on those are prone to be in bad shape where they meet the throttle body. If grounded (in other words, break in the insulation and the wire is grounding to the TB or air cleaner) the injector would stay open as long as the ignition had power. Inspect the wiring.

Pump will be set to prime the system after sitting with the key off for ~15 seconds, you could disconnect that injector and have someone turn the key to run (not start) while watching, if it sprays fuel disconnected, you know the injector is bad.

I wouldn't replace any of the components until you figure out the problem. Old GM parts are better than new GM parts, things like the IAC and TPS, IMO should not be replaced until they are demonstrated to be the problem.

Not to mention, throwing money at a problem doesn't help one stay on a budget.
 
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In rebuilding the TBI, a piece came out of the pressure regulator that looks like a mini horseshoe. I’m trying to figure out where it goes and what it does to no avail. Hoping someone can shed some light on this.

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