Cadillac Owners Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1 (Edited)
I'm purchasing an Olds 307 out of a '87 Fleetwood Brougham and I just have a few questions first. I know it will match up to the transmission fine and the engine mounts are the same but that's about all I know.:confused:
If anyone out there has done this before I just need to know if there are any necessary steps to take before swapping and if there are any major modifications that need to be done. I almost forgot. Will the wiring harnesses be the same for both engines? Any input would be greatly appreciated. :thumbsup:
By the way. The engine will be going into my '85 Fleetwood Brougham.
 

·
Banned
Joined
·
23 Posts
Advice, yea use the 403 or 472/500 instead. :) I have a 307 with 100,200 miles includes cross over pipe and cat that I would sell cheap. I am the second owner and it ran perfectly when I took it out of my 88 Cutlass this summer.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #3
Vern said:
Advice, yea use the 403 or 472/500 instead. :) I have a 307 with 100,200 miles includes cross over pipe and cat that I would sell cheap. I am the second owner and it ran perfectly when I took it out of my 88 Cutlass this summer.
Well, the 307 is already paid for. I just need to pick it up from the junk yard. I just need to know if there will be many differences in the wiring or any modifications that will need to be made. I bought the 307 for $550, and I figured anything would be better than that 4100. The 307 only has 68,000 miles on it also.
 

·
Banned
Joined
·
23 Posts
CirKlek The 307 is low power and not cost effective with regards to performance mods. But the later ones especially are very smooth like a fuel injected car and they are very durable. I have seen lots of them with 200,000 miles. I hope somebody can help with your questions. $550 ouch around here you could get one for around $200 just because nobody wants them. Good luck
 

·
Registered
Joined
·
12 Posts
Discussion Starter #5
Thanks for the input Vern. :thumbsup: Basically I just want something that is more reliable than the 4100. I'm not really looking for too much power. How come nobody wants these engines anymore? Is it just because of the power issue? Maybe I did pay a little much but this is my first attemp at an engine swap so I figured I'd take what I could get. Plus the engine is in really good shape.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #7
davesdeville said:
I'm in ABQ too, just curious what junkyard did you find that in?
Yeah, I noticed that you were in ABQ. too. Well, I found the motor at Coronado Auto Recyclers in a recently arrived Fleetwood Brougham. I have noticed in other posts that you are pretty knowledgeable about these cadillac engines. Do you know if this is an easy swap to do?
 

·
Banned
1995 ETC, 75 Deville, Cad500 powered 73 Apollo, 94 Mark VIII
Joined
·
7,971 Posts
The 307 swap? It should be a pretty easy swap, but I can't guarantee anything. I really don't know too much about 82 to present engines. The physical placement of the engine doesn't present a problem. The computer system could be a problem, but I don't know because I've never had or worked on/around a car with a computer. Best of luck to you though.
 

·
Registered
Joined
·
26 Posts
CirKleK ,
I am not familiar with the '85/'87 Fleetwoods. Is yours RWD? If so, the Olds engine is a bolt in but you need the mounts from an early to mid '80's Olds Diesel car.
The 307 is better than the 4100 and is much more reliable/easy to work on. Also, if your car is RWD, the 200R4 transmission will suffice.
A 350 Olds engine is much better, but you already have the 307.
The price, while high, is not outrageous. A local junkyard wants $500 for a 60,000 mile engine, but they have had it for quite a while (at least two years) in a building. I guess they are hoping someone will eventually buy it. If they had sold it for less, I would have bought it. Instead, I have seen the light and converted to REAL Cadillac power (472/500's). I paid $250 for an excellent running '72 Eldo 500 (in an '81 Coupe). I repaired the front-end damage to the car and am currently driving it. The engine alone was worth what I paid for the car. The reason I got the car/engine so cheap is because it was SITTING for over two years. As with the laws of supply and demand, since there was no demand around here, the junkyard sold it for whatever they could.
I say this because I performed the swap on one of my '84 RWD Coupes. I replaced the 4100 with a '72 Olds 350. This car will also get a 500.

CirKleK said:
I'm purchasing an Olds 307 out of a '87 Fleetwood Brougham and I just have a few questions first. I know it will match up to the transmission fine and the engine mounts are the same but that's about all I know.:confused:
If anyone out there has done this before I just need to know if there are any necessary steps to take before swapping and if there are any major modifications that need to be done. I almost forgot. Will the wiring harnesses be the same for both engines? Any input would be greatly appreciated. :thumbsup:
By the way. The engine will be going into my '85 Fleetwood Brougham.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #10
Cadillac Pat, what type of diesel car did Olds make that I can get a set of motor mounts out of? Will the ones from the Fleetwood not work? Also, since the 4100 is fuel injected will this pose a problem when switching to the carburated engine? I think I've heard of just pulling the fuses for the fuel injection but I'm not sure. And in response to your question, mine is rear wheel drive so it will bolt right on to the 200-4R transmission. Thanks for your input, it will help, and I hope you can help me with my last few questions.
 

·
Registered
1991 Cadillac Brougham D'Elegance 5.7 Litre, 1994 DeVille
Joined
·
6,796 Posts
If the 307 has a carburetor all you really need to do is wire in an ignition system for it and run the lines to the carb. You'll have to keep track of what wires are for the temperature sensor and oil pressure sensor. I think that's pretty much it.

The way I rememebr it is that a carburetor needs less pressure then fuel injection so I don't know if you could still use the electric fuel pump that's there or a different one. If there's an old style mecanical pump on the engine you probably don't need to use the one on the car at all. But I don't know what GM did with this and I don't know the 80s Broughams.
 

·
Registered
Unicycle
Joined
·
11,009 Posts
brougham said:
If the 307 has a carburetor all you really need to do is wire in an ignition system for it and run the lines to the carb. You'll have to keep track of what wires are for the temperature sensor and oil pressure sensor. I think that's pretty much it.

The way I rememebr it is that a carburetor needs less pressure then fuel injection so I don't know if you could still use the electric fuel pump that's there or a different one. If there's an old style mecanical pump on the engine you probably don't need to use the one on the car at all. But I don't know what GM did with this and I don't know the 80s Broughams.
The 307 has a mechanical fuel pump off the block....

....yeah I can't imagine a high demand for the 307....no power, no aftermarket etc.... although it is a reliable enigne and never, ever dies, pretty solid too....just no power......nothing like keeping my foot to the floor in my moms '89 Brougham for about 1/4 just to get up to 60mph...... but the engine has gone through about 6 overheats in the last 5 years and was not even slightly affected by any of it......
 

·
Registered
Joined
·
135 Posts
4100 is a cursed machine from the get-go... "No one should have to tolerate a car like that".. words directly from GM... I will even go to say that a diesel is a better car than a 4100 as at least you have some heavy duty hardware to work with, a broken 4100 is just a mess to get out of the way, and dont even think about going back with one.

It is pretty tough work to do what you want properly, but the best way to attack it is to have another entire car with a 368/425/500 as a donar and change it ALL over including the transmission, brackets, etc and the differential, front springs and more from a 77-81 REAL cadillac big block car. Your 4 speed metricTH200 is almost as bad as the 4100 and will be your next project soon... Take care of it now! If you dont do it right, you are going to have a life long project on your hands due to just throwing and engine in where it does not match up to the parts around it.... A 307 is a good engine, but it has no business being in a Fleetwood and was just an easy fix to dump the failing HT4100s before cadillac went bust. Its a great engine in a smaller cutlass. If you had an original 307 car, a 403 would be your choice, but you dont... You have an HT4100.

If your 4100 is not a totally mint car, I would not even put this effort and money into is as it would be in vain should the car not be a real gem to begin with . It really is a major project to do correctly, but only a really nice car will your efforts will be rewarded. I think that if you are even doubting your cars condition, it would be cheaper and your efforts would be more rewarded by looking at another car that was not a 4100 and going with that. I hate to say this, but you will understand what I am saying once you are underway with the project should you attempt.

If your car is nice and if you are motivated to do this, I am sure you can look in the paper and find a family that just cant wait to get rid of some old cadillac they inherited for near dirt that would be a nice donar ,77-81 car for a good 4100 candidate swap... I would go for a 425 or 500, simply because its the same amount of work to put any other engine in the car, might as well do it the best you can the first time as the difference in price is really not much. I can tell you first hand on numerous swaps, the bigger engine you put in the car, the more you are going to like it. The cadillac motors are far superior to any of the post 81 alternatives for these cars.

If you already bought the 307 and the salvage yard will not refund you... My advice is to have the salvage yard keep the 307 and apply the money to find you a running wreck of a 77-81 RWD carburated cadillac..entire car...... This is what you need to do the job right.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #14
Ultra Slow, I appreciate your input. I think what I got from your reply was that it is a complete waste of time to put in a 307. Won't it fit alright if I'm getting it out of another Fleetwood? I'm kind of feeling discouraged now. Maybe I should have asked for input first before I bought the engine. I don't have it yet so I might be able to pick up something else but I don't have room for another whole car. I figured it would fit just fine since it's from another Fleetwood. I don't really need anything huge, just something to get me going that's reliable. How many man hours would it take to put in this engine? Are there a lot of modifications that will have to be made? I don't want to have to drag this on for too long. If this is a real waste of time just tell me straight up. Thanks.
 

·
Registered
1991 Cadillac Brougham D'Elegance 5.7 Litre, 1994 DeVille
Joined
·
6,796 Posts
It'll fit but what he's saying is that it's the same amount of work to put any engine in it so you should get one that has more power then the 307.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #16
brougham said:
It'll fit but what he's saying is that it's the same amount of work to put any engine in it so you should get one that has more power then the 307.
O.K., I understand now. Thanks for reassuring me that it'll fit. Maybe I can try and find a bigger one but if I can't I'll just stick with the 307. Thanks.
 

·
Registered
Joined
·
26 Posts
CirKleK,
The reason for a whole car is that while you don't need the whole car, you do need the entire drivetrain if converting to a 368, 425, 472 or 500. The Olds engine will get you what you want, reliability. To use it, you need the brackets/mounts from a similar car...ie and '80's RWD Cadillac that came with an Old's diesel. With the 307, you can keep the trans and the rest of the drivetrain. Upgrading to the bigger Cad engines requires a complete drivetrain change as the TH200R$ is not strong enough and the TH400 will not like the small rear and low gears. The big engines (368/425/472/500), make lots of torque and only need high gears.

Pat

CirKleK said:
O.K., I understand now. Thanks for reassuring me that it'll fit. Maybe I can try and find a bigger one but if I can't I'll just stick with the 307. Thanks.
 
1 - 17 of 17 Posts
Top