Lt1 in 78 malibu
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We retrofitted the Z28 radiator and dual fans. Since we kept all of the electronics from the Z28, the fans are controlled by the PCM just like they were designed to from the factory. Both fans come on together in either low speed or high speed depending on the cooling requirements. They have yet to even require high speed. The low speed has been adequate so far.
I'm not familiar with the carb conversion kits or the opti block off. Does this setup still retain LT1 reverse flow cooling system with the water pump driven off the camshaft?
Did the radiator fit well? I need a radiator anyway. Was wondering with the reverse flow requires the radiator it came with although i dont see why it would.
Yes, carb swap does still retain factory water pump. You can also go electric pump which installs into the stock casting (may go that route, not sure yet) Opti goes away with a blockoff plate and a distributor can be stabbed in the SBC location. The carb intake is available for LT1 thru GMPP
It fits the general dimension well. i think we trimmed part of the Malibu rad support on the bottom so the location of the drain spout for the Z28 radiator would not be obstructed. Also trimmed the post mount off the bottom of the Z rad on the passenger side and used the Malibu type tank bushings on both sides. For the top mount we used the plastic support from the Z28 and trimmed part of it away and drilled some mounting holes. It wasn't a complicated process. Although I wouldn't consider the installation anything near show quality, its very solid and functional. You'll see once you set it in there the type of stuff you'll need to tinker with. Thats the trimmed Z28 top mount piece in the pic.
Man I am diggin' the wagon. Love it. So then did you use z28 rad. hoses? And the steam line from the back of the heads tees into the return (upper - return to rad. From motor) radiator hose right? I was wondering how coolant doesnt back feed up that line back towards the heads
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On the Z28 there is coolant running through the throttle body as well as coolant running through the factory oil cooler. I deleted the oil cooler and bypassed the throttle body coolant flow. Because of this I only needed one return location from the pipes. You see the radiator cap and the plastic overflow hose? Just below that there's a fitting on the Z28 radiator. That's where you'll see the shielded rubber hose where the steam pipes system returns to the radiator. Instead of using the Z28 upper rad hose with T, I used an upper hose from an LT1 Caddy Fleetwood (no tee in upper hose)
Coolant wont flow back to the heads through that fitting. The the reason is the LT1 has reverse flow. So, the water pump pushes coolant through the front of the heads first and then down through the block second. So, the flow from the steam pipes is forced back to the radiator at this upper connection.
Coolant wont flow back to the heads through that fitting. The the reason is the LT1 has reverse flow. So, the water pump pushes coolant through the front of the heads first and then down through the block second. So, the flow from the steam pipes is forced back to the radiator at this upper connection.
Ok gotcha. So you have the steam line going directly into the radiator. I think I will be using the tee method, and also running heater hoses with restrictor valve, but like you will not be running an oil cooler.
I need to buy a radiator regardless. I have been debating whether to use the Z28 radiator or use a fit-for-gbody radiator, such as an aluminum aftermarket. I am running standard trans so will not need trans cooler lines/bungs either.
JD was it you that's running the B Body water pump? I thought about running either B or Y body pump cause there is no oil cooler line. To minimize having to cap things off. Wasnt sure if that would create an issue with accessories lining up.
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