Head Swap Options For 5.7L 350 TBI Engine

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Majoraslayer

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I would avoid the LT1 personally, just to reduce the time messing around.
That seems to be the consensus. I basically spent $400 to inherit someone else's problem. Everyone hates the LT1 and avoids them, which is probably why I had never heard anything about them before. There's probably no chance anyone will ever buy this thing; I would have been better off just setting fire to my paycheck to save the time it will eventually take hauling it off for scrap.
 

tayto

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LT1 is a great motor, if I didn't try to get collector plates on my Squarebody, it's what I would have swapped in there. it shares the same mounts as SBC, so the only thing to sort out is accessories and what you want to do for a distributor. I am not sure what the big deal with the water pump is, it spins the same direction as the TBI/TPI/vortec pump which are reverse direction compared to a regular SBC. you can also swap to an electric water pump which the LT1 guys have been doing for 25+ years. The biggest hurdle is getting a regular distributor in. you would have to buy the LT1 carb intake and get a distributor hole machined in.
 

Majoraslayer

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LT1 is a great motor, if I didn't try to get collector plates on my Squarebody, it's what I would have swapped in there. it shares the same mounts as SBC, so the only thing to sort out is accessories and what you want to do for a distributor. I am not sure what the big deal with the water pump is, it spins the same direction as the TBI/TPI/vortec pump which are reverse direction compared to a regular SBC. you can also swap to an electric water pump which the LT1 guys have been doing for 25+ years. The biggest hurdle is getting a regular distributor in. you would have to buy the LT1 carb intake and get a distributor hole machined in.
Isn't the water pump driven by the timing chain or something? Will a TBI pump even bolt onto it and work? As I understood it just trying to Google around, the OEM water pump is designed around the Opti Spark system and integrates with the timing set, which also drives the distributor. Replacing the distributor itself shouldn't be a problem with an accommodating carb intake, but by the time I change the entire accessory setup and run electric fans, as well as buying a $500 carburetor intake plus the cost of a TBI adapter, I would have come out cheaper and easier just using it as a doorstop and buying a completely different block for my original plan. It's not that I think the LT1 is a bad block, it's just the worst possible block for a direct swap on my truck.
 

L31MaxExpress

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LT1 is a great motor, if I didn't try to get collector plates on my Squarebody, it's what I would have swapped in there. it shares the same mounts as SBC, so the only thing to sort out is accessories and what you want to do for a distributor. I am not sure what the big deal with the water pump is, it spins the same direction as the TBI/TPI/vortec pump which are reverse direction compared to a regular SBC. you can also swap to an electric water pump which the LT1 guys have been doing for 25+ years. The biggest hurdle is getting a regular distributor in. you would have to buy the LT1 carb intake and get a distributor hole machined in.
The LT1 carb manifold already has a distributor hole. I forget the exact size freeze plug but a freeze plug blocks the opti spark hole in the timing cover. Unbolt and remove the oil pump drive and an HEI with a melonized gear drops right in.
 

L31MaxExpress

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Keep the crank driven water pump. I almost went with a LT4 based build in the van rather than a L31 SBC. The biggest issue I found or rather ran into is I really needed a high mount Corvette acessory setup and some re-engineering of alot of ac plumbing to keep both the front and rear ac. I also could not find specs on the Vette compressors displacement.
 

L31MaxExpress

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The LT1s cooling system is not difficult. The water pump hooks to hoses and does its thing. The nice thing on a LT1 or LT4 if you ever lose the belt, the pump keeps on turning. So you can limp it off the road easily.
 

tayto

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The flow is reversed on the LT1.
ya I know that, i guess I don't see why it matters what direction it spins since it's driven by the cam. i assume OP think there's an issue with the accessories? the only issue I could see was the low mount AC unit (I have a caprice LT1) has clearance issues, which can be solved by modifying the frame. I swapped an LT1 into my late 80s Caprice and just heated the frame rail with a torch and them clearance the with a hammer .
 
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