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Engine Swap: 1990 Cadillac Sedan Deville


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I have a a '90 Sedan Deville. To be honest my friend was telling me that rebuilding my engine would be a waste of time, because the manufacture makes it hard to find rebuild kits for this year. I search the web and cannot find any performance parts for my caddy, no crate engines...nothing..... Do i have to swap this engine out for something that gives me more performance? I do not want a street rod caddy or anything, but I would like a performance engine in my car. Are there not aftermarket cams and stuff like that for my year? I always search the web and come up empty. Are there other engines I can swap out with? WHERE ARE THE PERFROMANCE PARTS AT... RAARRR!!

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You can try Allante heads and fuel injection; that engine was rated at 200 hp (your engine was the best non-Allante 4.5 at 190 hp) and they did not change it when the 4.9 came out. The fuel injection is radically different from that used in the other 4.5 engines. The heads may or may not be the same; someone with a 1990 FSM can tell us. I don't know whether the PCM would compensate when the tuning on the fuel injection is working or whether you would need a chip. The Allante PCM *might* work.

Other changes, like putting in a 4.9, would be more expensive than just getting a 1991 or 1992. A Northstar drivetrain switch would be more expensive than a used 1993-1999 model.

There are aftermarket turbo conversions that can be configured for a lot of cars. The exhaust on the front head has a crossover to the first Y pipe in front of the cat that presents a problem with a turbo conversion. This crossover is why you don't see headers for FWD cars.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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What is wrong with the current engine that you need to rebuild it or replace it?

All parts to rebuild it such as bearings, seals, etc. are available - if not from GM, from the aftermarket.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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One of the reasons you don't see a lot of rebuild kits on the market is that this engine has been out of production for 23 years, and few of them ever needed a full rebuild. Aso, Cadillac was only 2.8% of the market in 1990 and thereabouts. You should be able to get whatever you need as parts or gasket kits, though.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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