Carburator Deville 472, 69 vs. 72

[Soren Johnson]

What differs the carburators on the 472 engine, 1969 and 1972?
Is it at all possible to convert the 72 carb to work on the 69 engine?
What should in that case be done?

[TJ Hopland]

Did you just get the 69 block and heads and the rest came off your 72?  It should be workable but it would have been ideal to keep the whole 69 setup.   I dont remember what was the problem with the 72?  Did it ever run right for you?   Just trying to figure out what you are using as a base line for how it should be performing and if some of the original problems may be parts you still have.

One thing they never could seem to leave alone over the years was the choke I know there were times it was round and other times it was a rectangle.    The number of, timing, and pressure on the vacuum ports often changed year to year depending on the equipment it needed to control.   Often the cams changed year to year so they changed the general tune of the carb and the timing curves to match and meet the emissions of the day.   Even different models came with different carbs like say and eldo vs a deville.   Not sure what was really different since the engines were pretty close but there must have been some slight differences.  The basic cruise operation is pretty simple on a carb, you are pretty much operating on the main jets and pretty basic physics.  Where it gets all complicated is all the transitional states.  That is where all the extra bits and tweaking and differences come in. 

There was a period in that era where the exhaust crossover under the carb was open so you had to use the proper base gasket and even at that I guess they are somewhat prone to burning up. 

A stock 69 engine is going to want to run premium gas. 

A 69 still has the plastic timing gear problem so hopefully before it went in someone put a metal chain set in there. 

 

[Soren Johnson]

If I get a -69 carb, will my -72 air cleaner fit?
Checked eBay, and Edelbrock seems to be a often sold carb there.
Is that a good carb or should I stick with original?
Does original air cleaner fits on Edelbrock?

[TJ Hopland]

If your engine is original ish the original ish carb is usually going to be your best bet.   The 69 used a Q jet as did the 72 so they would both be the same air cleaner.  The air cleaners on the 68-79 were pretty similar.   There were slight changes to various ports over the years but overall they were about the same.  They all were slightly offset to the back and then sort of hung down around the carb.  They all used a offset bolt in the center of the carb.   This was all to clear the AC compressor and for hood clearance on the eldos.

The edel that is normally sold as a replacement for the Q jet is very similar to the Qjet so the air cleaner should fit it.   The catch would usually be the fact that the air cleaner housing sort of hangs down over the carb if there are differences in some of the linkages it may not clear as well.    In a RWD car and with no AC just about any air cleaner will fit. 

Another catch is the Cadillacs used a switch mounted to the intake that interacts with the throttle linkage on the carb for the transmission kickdown.  Not sure if this switch would work with the Edel.   I am also not sure how well the linkage would work out with the cruise control. 

[TJ Hopland]

What issue are you having right now?