grasby

just got an 86 fleetwood..

9 posts in this topic

alright, so i recently got an 86 fleetwood brougham with a 5.0

and im kinda interested in an engine swap

so what engines will fit into my car?

and a little more specifically

(this may be a stupid question but...)

can any of the northstars fit into my car?

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The 1986 Fleetwood Brougham came with the 307 cid V8, which was made for Cadillac by Oldsmobile and is a very good engine. It's an all-iron V8 mated to a THM200-4R, a four-speed automatic with overdrive and lockup torque converter. In good condition, this is a hard combination to beat for the 1986 time frame. My first line of defense would be to get the engine and transmission into good shape; be sure that the timing chain was replaced if it has over 65,000 miles on it. If you want more power, I would look at performance options for the Olds 307 such as a switch to the VIN 9 heads, cam and carburetor to go from 140 to 180 hp. You may already have this if your drivetrain is VIN 9. Or perhaps a switch to an Olds 350, 403, 425, or 455 might be considered if you are looking at used engines. But any change you make will almost certainly require that you fabricate the accessory brackets for the alternator, A/C compressor, etc., and getting the fan belt pulleys to all match up may be a challenge.

If you are interested in a Northstar, you need to know that your car might have an electronically controlled carburetor but the Northstar is a totally computer-controlled engine, and a PCM or ECM is needed to perform the functions of the distributor and drive either four or eight ignition coils. Also, a Northstar weighs 355 pounds which is about 300 pounds less than an Oldsmobile V8 so you will need new front springs and shocks to level the car. Check with chrfab about a Northstar engine, bell housing, carburetor and intake manifold, and PCM for your car. They have DFI options with ECM too, which may open up the use of a 4L60-E or 4L80-E transmission.

Something less expensive and with more performance options would be a Chevrolet 350 engine. It will mate with your existing transmission and work well with it, and you can just about dial in whatever performance you want. If you go over 300 hp, you might want to look at rebuilding your transmission or replacing it with a THM700-R4 or 4L60 (not E), which is the same transmission. A 200 hp engine would be a real pleaser, and up to 350 hp would work OK with your transmission and make you rethink your brakes, tires and handling. With high stall rate torque converters and a beefed-up THM700-R4 the sky's the limit as far as horsepower is concerned.


CTS-V_Dashboard.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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thank you so much, thats a lot of info to digest

but thank you, very detailed, should really help

ill start lookin into that chevy 350 i think

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You will need the bell housing from the Cheverolet to mate your transmission to the Chevrolet V8. If the Chevrolet V8 has a THM350 transmission, the bell housing is the right one because the THM350 has the same bolt pattern as the THM200-4R. You will need to work out the motor supports but that's the main issue. Hooking up the wiring harness and making the exhaust work are simple things.

Be sure and take pictures and post them here.


CTS-V_Dashboard.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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yea thanks, my firneds dad has a 350 he might sell me

i just gotta pull it out of his suburban first

proba a project for this summer

once again, thank you much for the advice

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Keep a digital camera handy, open an account on photobucket, and come back here when you start the job. Even if you don't need help, we would all like to "watch."


CTS-V_Dashboard.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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That would definately be something I'd like to see. A 455HO would be even better... ;)


-95 Gold DeVille 4.9 87,000 miles

-92 Plymouth Colt Eclipse Turbo Engine Swap

-90 Plymouth Colt 12 Valve Engine Swap

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Cadillac Jim, I also have a 1986 Fleetwood which was my dad's last of many Cadillac's. My dad was known as the Cadillac Man. I promised to keep it & want to restore it, I was hoping to someday drop a

Year: 1975

Make: Oldsmobile

Model: Toronado

Cylinders: 8

Vin Code: W

Engine Size: 7.5

Part Number: DOG05

Engine Info:

OLDS 455 72-76 COMP ENG

Brougham.

Can you give me your thoughts on that. Thank You

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I believe that the 1975 Toronado is front wheel drive, and as such putting that engine in a rear wheel drive car may be a challenge, although the listing you give is "72-76" and the 455 was used in the Toronado only in the 1968-1970 model years so the engine mounts, accessory brackets, etc. may be the same for the 455 block and heads over that year range. That does NOT mean that the 307 accessory brackets will bolt to the 455. The 455 came in two flavors, 375 hp and 400 hp; the VIN code "W" probably means the 400 hp version. The Olds 455 is probably within 100 pounds of the 307 so that should not be a big problem, but it is a "big block" Oldsmobile while the 307 is a "small block" Oldsmobile and the weight may be significantly more than that of the 307; I would weigh an example of both engines at a recycling yard to be sure. The deck height of the 455 is higher than that of the 307 by 1.3 inches, so you may have a problem with hood clearance.

An easier switch at less cost, with easier-to-find parts and maintenance, is the 350 cid Chevrolet engine. The Olds 350 is another possibility.

The 307 of 1986 was a fine engine for its period, as I said in the original thread in 2009. Unless you are interested in making a project car out of this 1986 Fleetwood (suspension, brakes, transmission, rear axle,...), you might consider restoring that engine, or possibly upgrading it to the 180 hp version if it isn't already. Look at the 8th digit of your VIN; if it's an "8" you have the 180 hp engine.


CTS-V_Dashboard.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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