472 Tech, cam, etc.

[spastic_chicken]

Last year when I parked my '72 Supe, I was aware the engine was going to need some work come springtime (I don't have the luxury of a garage). There are some really bad timing issues, I'm not sure if the timing chain jumped or what. I replaced the timing chain about 8 years ago to replace the crappy plastic shit. But I think it's probably time to replace it again. I've talked myself into a new cam as well. I have a nice set of decked, lightly ported heads that I plan on swapping while I'm doing all this. And while the parts are off the engine, I'm going to powdercoat the intake (I'd love an edelbrock 2115, but i don't think I have hood clearance), brackets, and such. (If you need powdercoating done, let me know). I have some knock off Sanderson style block huggers, but someone told me they won't work (anyone know??)

This is in a 72 Superior. Turbo400: OEM style converter, Transgo shift kit, Red Alto clutches. This car is obviously a cruiser. I do a lot of car shows/cruises, and a lot of local parades during the season. Every once in a while as a novelty I like to take it down the track.

- This is the cam I like so far, but I haven't settled on:
MTS #5 Series - "The Performance + Cam"
RPM range: 1,000 - 4,500 / Advertised duration range: 258-266* / Duration @ .050” range: 208-215* / Valve lift range: .495-.510”.

- I'll pair this with new springs & lifters.

- Replace timing set

- might need new balancer

- replace gaskets

- make it look nice, paint and powdercoat where I can.

Okay, here are some of the questions I have (Sorry for the rambling - ADHD)

I would like to do this work with the engine in the car, if possible. Is there a way to change the cam bearings with the engine in the car?

How do you do a smog/air pump delete?

Does anyone know about headers for this era of coaches?

I would like to do this as the weather is getting nice, but I will be trying to devote most of this season to installing a turbo diesel in a 57 Eureka. Bottom line is, The work on the 72 needs to be quick.

[Morella]

You could probably get a better answer on the MTS or Cadillac forums. It has been a while since I worked on a BBC, but I'll try.

I would like to do this work with the engine in the car, if possible. Is there a way to change the cam bearings with the engine in the car?

I've never tried it with the 472, but I do recall that on some engines, the cam bearings get progressively smaller in outside diameter as they go toward the rear of the engine. If this is the case, and you have the cam bearing installation tool, you could probably do it, but keep in mind that you would have to have enough clearance to get the tool in there, behind the radiator and condensor. It would be much easier to pull the engine, and then you could replace the motor mounts, fix any oil leaks, and clean it up.

A new hi-V water pump and hoses would be good, if you're not into taking stuff apart more than once. Beware of the threads in the timing cover. They almost always strip when you remove the bolts. If any of them are stripped, the best repair is to tack weld a shear nut onto the back side.

The timing chain problem just doesn't jump and jive for me, unless you've put a whole bunch of miles on it since you replaced it last. Replacing the chain with a double roller chain is a good idea, but I would check to see if there is another problem first. You can check the hysteresis by turning the crankshaft in each direction and watching the distributor rotor. If there is more than a few degrees of slack, then you have a problem. They don't jump unless they're really stretched.

How do you do a smog/air pump delete?

There are a few ways. If you're powder coating the intake, then I assume that you care about appearance, so the best one is probably to use the pulleys and brackets from a 77-79 425 no-smog engine. Biggest problem is that the alternator is driven by the smog pump.

You're not going to use headers with the stock exhaust system, are you? Most people I've known who have installed headers have replaced the whole exhaust system with something that was tuned for the application. Doing modifications to your engine requires some research, because if the cam, the gears, the C/R, and the flow don't match, whether or not your mods are going to to any good is a crapshoot.

-d

[spastic_chicken]

Anyone??

[EternalCombustion]

Ok, I have done most of what you have listed to my '72 S&S. Which they should be the same since they are both commercial chassis.

First off, I don't know about the cam bearings, but with the radiator out there is quite a bit of room up front.

I used the sanderson headers but some mods had to be made. I had to shave a couple of tabs of metal around where the upper shock bolts were. I had to beat a slight flat spot in a couple of places on the right header. And finally, because it was still pretty tight, I had to strap the engine down to keep the engine from flexing the rubber motor mounts. So, it doesn't rattle. It may occasionally still make a little contact during high torque but it is not that bad.

I also, used the edelbrock #2115. If you use a drop base air cleaner you can get it to work. However, if you want to keep AC on it you will have to replace the compressor with a smaller unit. One of the little chrome sanden universal compressors will work. But you have to do a little modification to the AC mount. If I remember correctly the front original AC mount is made from a block of aluminum. You just have to a shape it to fit the new compressor.

You can remove the smog pump, but you will have to fabricate a new lower alternator bracket. You will also have to move the alternator a little closer to the engine block. The reason being is, you want the alternator to follow the belt tracking as that of the smog pump. You can still use the upper alternator bracket but you will have to bend it back a little. After this is done you will probably want to run a length of string around around the belt path to get the right length belt.

Let me know if you have any particular questions and I will try to help.

[Abnorml]

Here are 2 Cadillac sites that have performance parts for Big Block Cadillacs,

http://www.cad500parts.com/

http://www.cadillacperformanceparts.com/

[KnK68hearsedaddy]

I would like to do this work with the engine in the car, if possible. Is there a way to change the cam bearings with the engine in the car?

I don't know for sure about the 72 but if its anything like my 68 they squeezed everything in there tight enough that it could be possible but not without tipping the block which would be more hassle then its worth and probably would take longer then it would to lift the whole thing....... Plus the way it sounds your wanting to beautifie the block n what not which would be a total shit job if you left it in.

How do you do a smog/air pump delete?

Easy just pull it all out and puchase the threaded or straight plugs which ever is needed on those heads and cap the holes on the heads off

Does anyone know about headers for this era of coaches?

Ive been looking for my 472 and summit makes them but i've been doing some serious thought to custom headers or even straight pipes off each port but yes summit has a series of headers for classic rides you might check them or i saw a few in jegs

[EternalCombustion]

Easy just pull it all out and puchase the threaded or straight plugs which ever is needed on those heads and cap the holes on the heads off

Ahh, if only it were that easy. But you are correct the removal of the smog pump and it's systems is that easy. But you still must make the mod to move the alternator back. The reason is, at least on the '72, the smog pulley and belt is the only thing that drives the water pump. You must move the alternator back and run the alternator belt around the water pump and the crank pulley to keep everything running. If the only thing you did was remove the smog pump there would be nothing to drive the water pump or the alternator.