88' Caddy

88' Cadday

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Hello everyone,

My ride is 88' Brougham d'elegance Olds 307 c.u. 71K miles on the clock original miles. I bought 5 years ago from an old lady in Toronto after her husband passed away. The car in pristine condition inside out. However, the paint needs a little bit of attention some blemishes there and here. but nothing serious. Although the Olds 307 is under-powered, it pulls the car good. The car drives amazingly and I do not care about power that much.

I will send pics later of my ride.

Thanks for reading
 

Olds 307 and 403

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Awesome
 

Intragration

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Love the box Cadillacs. Please do post pics when you can. I still have a soft spot for all those old 307 cars. They were slow, but they were still Olds V8s. Just a reminiscence, but '88 when your car was new was when I was starting to get into cars. I was buying late-'60s to early-'70s cars. That was 32 years ago, and cars that age at that time were 1956s. Time flies ha ha.
 

88' Cadday

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IMG_20180629_205308960.jpg
 

Intragration

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Great car, very clean! Looks great in white. I assume that is the factory vinyl top. It's interesting, because I remember '88s having sort of a vinyl insert in the rear "opera window", that made it more of a porthole with vinyl trim around it. Did a quick search, and it seems both kinds exist. Maybe it was a mid-year transition to use up '87 parts? Do you know when yours was built?
 

88' Cadday

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Yes 87. The owner purchased it that year. I saw the original bill of sale when I bought the car
 

Intragration

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Come on man, let's see some more pics! You say paint problems, but she looks uncommonly clean and shiny to me.
 

Olds 307 and 403

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Looks in great shape, surprised the 307 can move that big car.
 

88' Cadday

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Yes, indeed. 307 produces enough power to move the car and considered to be one the most reliable engine of that era. The only thing that I hate about this car is the Computer Controlled Carb with too many vacuum lines. I know that I am getting very good MPG; however, I have been bothered recently with too many check engine lights throwing codes #21, #34, and #43.
 
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Olds 307 and 403

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Melville, Saskatchewan
Yeah, the CCC carb was kind of Goofy and can be a pain. We only got them for 86 through 90 up here. Olds tested the TBI, 3 intakes exist but decided to stayed carbed till the bitter end.
 
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Intragration

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Others will have a better answer than I will, but it's my understanding that you just need to replace the carb and the distributor. Thing is, if there's nothing wrong with them, it's a somewhat expensive and pointless effort with a 307. You won't get any more power, and your economy might go down, at least at low-RPM/idle.

One way to prevent check engine codes is to pull the circuit board out of the check engine driver module. It's a little green "can" that's hidden behind the glovebox. (See picture) You just flip open the top as shown, and remove the board that's inside. I don't know exactly what the codes you're getting mean, but they're essentially messages for things that would be happening anyway if you didn't have CCC, and by pulling the circuit board, you just won't be troubled with being alerted to them anymore.

Bear in mind, this advice is coming from someone who doesn't and wouldn't have CCC. It's probably a fine invention, but cars ran fine without it before it was invented. My car was originally CCC, but I converted it by way of putting a 455 in it. A 455 would fit in yours too... :giggle:

Picture 1577.jpg
 
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88' Cadday

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Others will have a better answer than I will, but it's my understanding that you just need to replace the carb and the distributor. Thing is, if there's nothing wrong with them, it's a somewhat expensive and pointless effort with a 307. You won't get any more power, and your economy might go down, at least at low-RPM/idle.

One way to prevent check engine codes is to pull the circuit board out of the check engine driver module. It's a little green "can" that's hidden behind the glovebox. (See picture) You just flip open the top as shown, and remove the board that's inside. I don't know exactly what the codes you're getting mean, but they're essentially messages for things that would be happening anyway if you didn't have CCC, and by pulling the circuit board, you just won't be troubled with being alerted to them anymore.

Bear in mind, this advice is coming from someone who doesn't and wouldn't have CCC. It's probably a fine invention, but cars ran fine without it before it was invented. My car was originally CCC, but I converted it by way of putting a 455 in it. A 455 would fit in yours too... :giggle:

View attachment 1117
Thanks for the advice, Intragration. I will look into this more closely.
Regarding to swapping the engine to better performance engine such as olds 350, 403, or 455. What is the best overall and easy to find of the aforementioned engines? Are all of them drop in engines? I heard olds 350 and 403 are the easiest to swap, right?
 

Intragration

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I'd imagine that the 350 and 403 would be easier to find, they're newer, and probably less in-demand than the 455. The 350 and 403 both have the same deck height as the 307, so they're technically closer to a drop-in swap. The 455 has a taller deck height, so the engine is taller and a little wider, and it uses different components such as intake manifold, brackets, and headers if you go that way. If you were able to find a fully-dressed 455, that would almost be a direct drop-in, except you'd probably have to do something about reconnecting the exhaust. The 350 and 403, I'm PRETTY sure that everything would be interchangeable, although if you got a motor that didn't have an intake, I don't think you'd want to swap over your 307 intake. But accessories should all bolt right up. Of course, if you're going in the direction of a swap, you'd definitely want to get the carb and distributor, as you're not going to want to move the CCC stuff over to a motor of a different displacement. I think it's technically possible, but not advisable.

Another consideration is transmission. I'm not sure what you have in there, but I'm guessing it's a 200-4R. Totally pulling this out of the air now, but those are fairly light-duty transmissions from the factory, but I believe they have fairly decent aftermarket support, as they also came in the Grand National. If this is it, I BELIEVE it could be beefed up. If you decide to change to something else, that could be opening a can of worms, with driveshaft length and crossmember pad location.

I'm pretty sure you have an 8.5" rear in there, which if that's true, it should hold up to the power, but gearing might be lackluster. I really don't know what gears it would have, but it could be something from 2.41 to 2.93. (Could also be something totally different.) Depending on what you have, a gear swap could actually be a pretty good supporting mod, if you were planning to keep the car and eventually upgrade the motor. If you had something like 2.41s, this is something that could be done sooner rather than later, and would probably make it more fun to drive in the short term. If you already have 2.93s, those actually aren't awful, and I think would work ok.
 

Olds 307 and 403

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A stock or mild 350 is an easy replacement. The 403 is a siamese bore motor, more torque but tends to run hotter. You also need to control the lock up torque converter unhooking the CCC carb and distributor. Something like a shift kit is a good idea with more power. Of course a D5 converter and maybe steeper gears, not a problem with a 2004R trans.
 

Intragration

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A stock or mild 350 is an easy replacement. The 403 is a siamese bore motor, more torque but tends to run hotter. You also need to control the lock up torque converter unhooking the CCC carb and distributor. Something like a shift kit is a good idea with more power. Of course a D5 converter and maybe steeper gears, not a problem with a 2004R trans.
Just out of curiosity, is there any problem running a transmission that has a lock-up torque converter WITHOUT locking it up? I suppose because it has a top gear steeper than 1:1, there is more mechanical resistance in 4th gear, and so therefore additional potential heat generation/efficiency loss. But is this a BAD thing, to not run the lock-up, or are you just leaving some additional economy on the table? Literally just curious.
 

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
It can create heat from the extra slippage, probably minimal in a stock converter. Plus the 300 rpm drop helps especially if he does a gear swap to help move this huge car. Between the .67 OD and the 250 to 300 rpm less with the converter locked up, drops rpm by about 1000 at highway speeds.