Majoraslayer
I'm Awesome
In another thread I mentioned I picked up an LT1 block from a 1993 Camaro by mistake. Since the quirks with this engine are going to make it hard to resell, I'm debating on finding a way to make it work in my truck. Buying all of the individual parts to do this would likely be more expensive than just buying a different 350 engine altogether and using my mistake as a doorstop. At first I assumed I was just stuck with a high performance, unsellable boat anchor. That's not to say the LT1 is a bad motor, it just doesn't make much sense to buy one unless you're specifically replacing one in your LT1 car. Anyone looking for a 350 SBC will be better off with any other block for flexibility options, and anyone looking for a more advanced EFI performance V8 swap would be more likely to just spring for an LS.
After thinking on it for a while, I realized I can probably pick up a junk LT1 Camaro for much cheaper than buying the parts separately, and just steal most of the parts I need from that. I've not made up my mind on this approach, but it's an option I'm weighing. There are a few possible contenders around me in the $400-$800 range. There's a valid argument to be made about just putting the engine in one of those Camaros if I bought it. That would make a lot of sense. I don't want to make sense with a 90s Camaro though, I want my truck with something cool in it.
The plan would be to (hopefully) take the wiring harness, PCM, radiator/electric fans, hoses, engine accessory brackets, and possibly engine accessories from the donor car and use them in my truck. To fuel it, I'd swap the TBI fuel pump with a direct fit Vortec pump to meet the fuel pressure demand. Of the few GMT400 LT1 swaps I've seen, several mentioned it wasn't a direct bolt-in because the LT1 motor mounts aren't aligned correctly, but I also read that the block has provisions to swap on older SBC mount brackets instead of modifying the frame mounting locations. I think one post I read mentioned that the bolt hole this uses in the block would mean losing a factory mounting location for one of the accessories (A/C pump maybe?) that can somehow be relocated. A costly chunk of this would also be investing in the LS coil pack conversion kit to eliminate the Opti-Spark.
Before criticizing me too heavily, keep in mind I'm just looking at options at the moment, so try not to be too harsh about how stupid this may be. I do have a few questions:
1) I have seen an old video on YouTube where someone had modified LT1 heads to use on an older 350 block, though I don't know how they got their coolant system working with them. That's not what I want to do, but I'm curious if someone here has done it so they could answer this question. I have shortie tube headers on my TBI engine now, running to a brand new dual exhaust. If anyone here has actually tried it, does anyone know if TBI tube headers would be able to bolt onto the LT1 heads? If they do have a different bolt pattern, does anyone happen to make shortie headers for the LT1 that might directly fit in place of my truck headers without modifying my new exhaust?
2) My truck has a 700R4. As I understand it, the LT1 came with a 4L60E behind it, which is basically just a 700R4 with computer management. Would it cause issues with the PCM's management of the engine not to have this control over the transmission? I'm sure the PCM takes data from what the engine is doing to determine shifting for the 4L60E, but I don't know if that goes both ways. Addendum to this question as well, does the 4L60E handle TCC lockup through it's special PCM connection, or is it controlled with the same 4-pin connector as the 700R4? Ideally I'd like to keep my 700R4 instead of having to do a transmission swap if possible.
3) I've seen several threads asking about swapping a Vortec pump into a TBI truck, and everyone says it's a straightforward swap. I understand it will attach right in, but what about fuel lines? I have OEM metal-braided lines going from the pump to the TBI, are these lines able to handle the fuel pressure required by the Vortec pump/LT1 fuel rail?
After thinking on it for a while, I realized I can probably pick up a junk LT1 Camaro for much cheaper than buying the parts separately, and just steal most of the parts I need from that. I've not made up my mind on this approach, but it's an option I'm weighing. There are a few possible contenders around me in the $400-$800 range. There's a valid argument to be made about just putting the engine in one of those Camaros if I bought it. That would make a lot of sense. I don't want to make sense with a 90s Camaro though, I want my truck with something cool in it.
The plan would be to (hopefully) take the wiring harness, PCM, radiator/electric fans, hoses, engine accessory brackets, and possibly engine accessories from the donor car and use them in my truck. To fuel it, I'd swap the TBI fuel pump with a direct fit Vortec pump to meet the fuel pressure demand. Of the few GMT400 LT1 swaps I've seen, several mentioned it wasn't a direct bolt-in because the LT1 motor mounts aren't aligned correctly, but I also read that the block has provisions to swap on older SBC mount brackets instead of modifying the frame mounting locations. I think one post I read mentioned that the bolt hole this uses in the block would mean losing a factory mounting location for one of the accessories (A/C pump maybe?) that can somehow be relocated. A costly chunk of this would also be investing in the LS coil pack conversion kit to eliminate the Opti-Spark.
Before criticizing me too heavily, keep in mind I'm just looking at options at the moment, so try not to be too harsh about how stupid this may be. I do have a few questions:
1) I have seen an old video on YouTube where someone had modified LT1 heads to use on an older 350 block, though I don't know how they got their coolant system working with them. That's not what I want to do, but I'm curious if someone here has done it so they could answer this question. I have shortie tube headers on my TBI engine now, running to a brand new dual exhaust. If anyone here has actually tried it, does anyone know if TBI tube headers would be able to bolt onto the LT1 heads? If they do have a different bolt pattern, does anyone happen to make shortie headers for the LT1 that might directly fit in place of my truck headers without modifying my new exhaust?
2) My truck has a 700R4. As I understand it, the LT1 came with a 4L60E behind it, which is basically just a 700R4 with computer management. Would it cause issues with the PCM's management of the engine not to have this control over the transmission? I'm sure the PCM takes data from what the engine is doing to determine shifting for the 4L60E, but I don't know if that goes both ways. Addendum to this question as well, does the 4L60E handle TCC lockup through it's special PCM connection, or is it controlled with the same 4-pin connector as the 700R4? Ideally I'd like to keep my 700R4 instead of having to do a transmission swap if possible.
3) I've seen several threads asking about swapping a Vortec pump into a TBI truck, and everyone says it's a straightforward swap. I understand it will attach right in, but what about fuel lines? I have OEM metal-braided lines going from the pump to the TBI, are these lines able to handle the fuel pressure required by the Vortec pump/LT1 fuel rail?
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