engine swap for 81
Thread Starter
Safety Car
Joined: Dec 2006
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From: NC
2025 Corvette of the Year Finalist - Unmodified
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engine swap for 81
I hav a friend who will be removing low mileage orginal 350 from 1981 auto. Plans to store the orginal and swap in gm crate motor. Currently considering the zz4 or the 350 ho. Does anyone have any feedback on this swap. Any areas to be aware of and any opinions on which would be a better choice. Will mainly be a street cruiser. Please feel free to offer advice. Thanks, got2hav1
Instructor
Joined: Jul 2007
Posts: 228
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From: Price Utah
350 ho
I purchased a 350 ho for installation in a 63 Chevy 2 and have been extremely pleased. It came from Pace performance. One item to be aware of is the camshaft lift limitation with vortech heads, about .480 lift with a 1.5 rocker arm. If a higher lift cam is anticipated have the valve guide area
cut for clearance. Comp cams sells the tools for this.
cut for clearance. Comp cams sells the tools for this.
Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
I have the GM Fast Burn. I love it. The only thing to be aware of is Water Pump. It is a reverse fow so you need to go with electric fans.
If you use the edlebrock 8812 pump you can use all of the factory pulleys and the pump clear the timming cover. There is a GM pump that fits a ZZ4 so you can use the factory pulleys but it will give you a lot of problems with timming cover clearance and leaks.
Good luck
If you use the edlebrock 8812 pump you can use all of the factory pulleys and the pump clear the timming cover. There is a GM pump that fits a ZZ4 so you can use the factory pulleys but it will give you a lot of problems with timming cover clearance and leaks.
Good luck
Thread Starter
Safety Car
Joined: Dec 2006
Posts: 3,936
Likes: 1,921
From: NC
2025 Corvette of the Year Finalist - Unmodified
2024 C7 of the Year Winner - Unmodified
2023 C7 of the Year Finalist - Unmodified
2019 C6 of Year Finalist (performance mods)
I have the GM Fast Burn. I love it. The only thing to be aware of is Water Pump. It is a reverse fow so you need to go with electric fans.
If you use the edlebrock 8812 pump you can use all of the factory pulleys and the pump clear the timming cover. There is a GM pump that fits a ZZ4 so you can use the factory pulleys but it will give you a lot of problems with timming cover clearance and leaks.
Good luck
If you use the edlebrock 8812 pump you can use all of the factory pulleys and the pump clear the timming cover. There is a GM pump that fits a ZZ4 so you can use the factory pulleys but it will give you a lot of problems with timming cover clearance and leaks.
Good luck
