Author Topic: Rebuilding a 472...  (Read 534 times)

Offline cadillac73

  • Posts: 18
  • Name: Cat Smith
Rebuilding a 472...
« on: November 21, 2017, 08:16:57 AM »
Hello all...I have a '73 Coupe deVille.  I am getting my 472 rebuilt soon.  The place that I have selected to do the work is asking me if I want any performance modifications/accessories/dressing the engine.  So I'm asking for your opinion.  Pretend money is no object (ha ha).  If you had a stock 472, what would you do?  She already has dual exhaust. Other obvious mods would be removing the smog pump and switching to HEI, but beyond that...?  What's your fantasy 472 and why?  Thanks!! 
Cat Smith
Pittston, ME  USA
1973 Coupe deVille 472
"Solid Gold"

Offline 1970DevilleLSX

  • Posts: 6
  • Name: Brian Cook
Re: Rebuilding a 472...
« Reply #1 on: November 21, 2017, 09:30:13 AM »
Me being me, I would absolutely get the heads ported/polished and spec out the right cam for making some extra power.  Anything that isn't necessary but stealing power away would get tossed. HEI definitely.  Turbo?  Twins?  The possibilities are endless.  I would also get a FI kit for it too - but that's based on "money no object" haha

Offline "Cadillac Kid" Greg Surfas 15364

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Re: Rebuilding a 472...
« Reply #2 on: November 21, 2017, 12:41:20 PM »
Cat,
You have quite a range of choices.  You can go full out and end up like my 73 which is just barely street able, though 12 second quarter mole times are assured, or since you are rebuilding the motor you can go to 10:1 forged pistons and an MTS #5cam. That combination will get you just about as much HP as the stock rear end can put to the ground without a continuous one tire fire.  Of course if you go to a much bigger cam with the valve train it will require, some head work will help.
I would suggest you contact Paul at MTS and talk about your expectations with him.
Just for reference I have attached the U-tube link for my motor.

https://youtu.be/3FyiMlsIdr8

Let us know how it works out.
Greg Surfas
Cadillac Kid-Greg Surfas
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Offline DeVille68

  • Posts: 448
    • CLC Member
      CLC Member #30616
  • Name: Nicolas Hubacher
Re: Rebuilding a 472...
« Reply #3 on: November 21, 2017, 02:59:06 PM »
I am currently rebuilding my 68 472cui - you can follow me here: http://forums.cadillaclasalleclub.org/index.php?topic=130360.180

Here is what I am planing on doing so far:
1) replace the 8.5:1 pistons with 10.5:1 from egge.com
2) moly rings
3) Cam #5 from MTS (or similar lunati or comp cams)
4) Maybe slightly larger valves, but only if I put hardened valve seats in
5) fresh timing chain
6) rebuild distributor HEI
7) light cleanup of the manifold and intake (no real porting)

My engine already has the 76cc camber.
I think this combination will work good for me, I use it as a nice cruiser.

@Greg: What "light" modification would you recommend?

Best regards,
Nicolas
1968 Cadillac DeVille Convertible (silver pine green)

Offline The Tassie Devil(le)

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Re: Rebuilding a 472...
« Reply #4 on: November 21, 2017, 04:17:52 PM »
Actually, if it is performance you are after, convert it to a 500.

The next best thing you can do after all the machining is done is a good balance job.

Bruce. >:D
'72 Eldorado Convertible (LHD)
'70 Ranchero Squire (RHD)
'74 Chris Craft Gull Wing (SH)
(Past President Modified Chapter)

Offline Dave Shepherd

  • Posts: 1933
Re: Rebuilding a 472...
« Reply #5 on: November 21, 2017, 07:56:35 PM »
I am currently rebuilding my 68 472cui - you can follow me here: http://forums.cadillaclasalleclub.org/index.php?topic=130360.180

Here is what I am planing on doing so far:
1) replace the 8.5:1 pistons with 10.5:1 from egge.com
2) moly rings
3) Cam #5 from MTS (or similar lunati or comp cams)
4) Maybe slightly larger valves, but only if I put hardened valve seats in
5) fresh timing chain
6) rebuild distributor HEI
7) light cleanup of the manifold and intake (no real porting)

My engine already has the 76cc camber.
I think this combination will work good for me, I use it as a nice cruiser.

@Greg: What "light" modification would you recommend?

Best regards,
Nicolas
. The 68 472 had 10:1compression oe.  I could see going down to use regular, but something's  odd about that piston change.

Offline "Cadillac Kid" Greg Surfas 15364

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Re: Rebuilding a 472...
« Reply #6 on: November 21, 2017, 10:14:28 PM »
Dave,
Going to a performance designed forged piston would be a natural if increased performance is what you are after.
Greg Surfas
Cadillac Kid-Greg Surfas
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Offline The Tassie Devil(le)

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  • Name: Bruce Reynolds
Re: Rebuilding a 472...
« Reply #7 on: November 21, 2017, 10:42:42 PM »
Forged pistons are not required for street.   Clearances required for Forged make for added noise, till the engine gets to the required operating temperature..

Bruce. >:D
'72 Eldorado Convertible (LHD)
'70 Ranchero Squire (RHD)
'74 Chris Craft Gull Wing (SH)
(Past President Modified Chapter)

Offline cadman56

  • Posts: 353
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  • Name: Larry Blanchard
Re: Rebuilding a 472...
« Reply #8 on: November 22, 2017, 07:06:15 AM »
Depends what you want to do with the car.  Call MTS and discuss it with them.
1956 Cadillac Coupe deVille (sold)
1956 Cadillac Convertible (sold)
1956 Cadillac Eldorado Seville
1967 Cadillac Eldorado (sold)
1968 Cadillac Convertible
1991 Cadillac Fleetwood Brougham dElegance
Larry Blanchard CLC #5820

Offline Dave Shepherd

  • Posts: 1933
Re: Rebuilding a 472...
« Reply #9 on: November 22, 2017, 07:09:14 AM »
I was referring to the plan to move up to 10:1 pistons from 8.5:1, when it already has 10:1, agreed, forged pistons are  a poor choice for a relatively stock low rpm engine.

Offline "Cadillac Kid" Greg Surfas 15364

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Re: Rebuilding a 472...
« Reply #10 on: November 22, 2017, 09:13:40 AM »
With all due respects, the OP stated he wants suggestions for performance improvement which I would interpret as he is going to put his foot in it.  Forged pistons if nothing else act as a bit of safety when somehow the octane of the gasoline is below the posted numbers or you have a bit too much advance. 
Greg Surfas
Cadillac Kid-Greg Surfas
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Offline TJ Hopland

  • Posts: 6824
Re: Rebuilding a 472...
« Reply #11 on: November 22, 2017, 09:15:26 AM »
I would buy as much as possible or maybe even everything from a place like MTS.   They have the experience to know what is the good stuff and what is junk and there is a lot of junk out there today.    I made the mistake of letting my shop get some of the stuff and it turned out that was the stuff that caused all the problems.   I didn't get any sort of warranty out of them because they didn't do the final assembly.   When I did compare prices they always seemed to be competitive on the stuff you could get anywhere so I just got it from them to help them out and make it easy on me too.  There are tons of vendors now that don't actually stock anything but imply that they do so you can run into lots of delays or even find out they can't actually get the part.

Make sure the shop doesn't mix up the sensors on the corners of the heads.  They look the same but are very different and at this age you may not be able to read any numbers.   Just label them front behind alternator and rear brake booster.   Also keep bolts sorted there are some that are only like 1/8 different in length or have or don't have a washer that will bite you if they get messed up like the ones that hold the cam sprocket on.   You get a guy that has Chevs memorized it may just be used to throwing all the bolts in one pile.  On final assembly remind them that the cylinder numbering is basically flipped from typical GM with the odd bank on the right.

If you are staying with stock covers I would spend the time cleaning the original hardware and re using it.   IF you are not going stock don't get typical bolts and washers, they won't stay tight especially on things like oil pan.  Find a hardware set that is like the OE where most of the bolts have the built in washer.

Have your shop weld nuts on the back of the timing cover for the small 1/4 water pump bolts.  They originally just threaded into the 'tin' cover and are easily damaged.  The nuts are totally hidden and don't interfere with anything.    The way to do it is thread a spare bolt into the original hole then spin the nut down on the back.  This will hold it for welding plus align it with the existing threads assuming they are still there. 

Have your shop carefully inspect the oil pan.  At this age there are often thin spots in the bottom from moisture being trapped.   Usually its pretty easy to braze up any thin spots they find.   Also make sure the threads for the drain are in good shape and its not bent up.

Make sure the shop takes extra time to knock all the crap out of the oil pickup tube/ screen.     

Rocker arms can be a problem.   Apparently someone is making replacements but I have not heard good things about the quality.   You hate to put sometimes questionable used rockers on a motor you spent a ton on making everything else like new.   There are decently priced shaft rocker sets now but they require you to go with new valve covers for clearance so keep that in mind when it comes to the budget and appearance.   Some rocker options require machining of the guides which cold also give you more/better seal options.

Most people would be ditching the smog pump at this point.  MTS has a pulley set so you don't have to search junkyards.  You can use the same brackets, the alternator hides most of the pump part of the bracket or you can just cut the smog part off if you want.  MTS has the plugs for the smog holes in the heads.   If you don't currently have working AC you can go to the later single groove setup for the AC/PS belt.  This leaves plenty of clearance for the HEI cap.  The single belt works on the dual PS pulley but looks a little odd since it rides high and has the empty groove.  The later single groove press on pulley pump setup is pretty common and easy to find.  Bolt on single groove was pretty rare since it was only a partial year thing. 

Get your exhaust manifolds cleaned up and surfaced at the same time and put them together with no gaskets like the factory did.

New cam is a decent idea.  GM cams from the 70's were a little soft so its likely showing some wear and they were doing strange things with the design to try and cope with low lead and emissions.   The cams like the #5 don't seem to hurt the idle so seem to be a good performance boost without wrecking the Cadillac style.     

A 73 should have come with the 76 cc (small chamber high comp) heads.   To get the lower ratio they went with a massive dished piston.  Lots of guys look at those pistons and scratch their heads wondering how that engine could run as clean and smooth as it did with that design.   It must have had issues because they only did it for 3 years before they changed the head design so they could use a more traditional piston.   74-76 was the 120cc head.

My research was a few years ago and for a 500 so things could be different today and for a 472.    If you want to stay low compression you may want to look into getting the later heads.   There may be medium compression options with your existing heads like something in the 9's which is a decent way to go.  You get a little more power but it should not be as tricky to tune or sensitive to the gas you use.   High compression with your existing heads should be the easiest to do but then locks you into premium gas and a the tune is a little more critical.   

Changing to a 500 should not be a huge deal with the motor apart either,  difference was just crank and pistons.   A place like MTS could likely send you a rebuilt 500 crank ready to drop in.

Once you get an idea what you want to do ask about what pistons and such may be in stock and if anything is on sale.   When I did my motor MTS had some 20 over pistons for like a 1/4 the price of the more common 30's.  Sadly I think it took 40 to clean up my block.   
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
75 Eldo rusty but trusty
80 Eldo Diesel
And other assorted stuff I keep buying for some reason

Online cadillacmike68

  • Posts: 1237
  • Still finishing up this 1968
    • CLC Member
      CLC Member #15823
  • Name: M Santos
Re: Rebuilding a 472...
« Reply #12 on: November 22, 2017, 08:04:31 PM »
I've gone through this twice now. The engine just got re-assembled last week and put back in the car. I'm not home, so can't comment on how its running, but this is what I did and here are some of my observations.

First, while MTS can be a source for a lot of parts, they are EXPENSIVE. RockAuto, Jugs, & Summit should have most or all of the parts you would need, Except for a crankshaft - that will be Hard To Find if you need another or want to go to 500 CI. Even amazon has some of the parts needed.

Pistons: I wouldn't go higher than 10:1, its just too high for the gas that's available unless you have access to 100 or 110 octane fuel to mix in. I have Keith Black # 395 pistons (I think) for 10:1 while my original was 10.5:1. The heads were shaved slightly in 2005 so actual compression is a tad higher. I used KB moly rings as well

Cam: I had a comp cam cam put in, don't know the model #, but I can look it up when i get home.

Valves: new valves with original size and hardened seats.  No porting of heads or manifolds, but they were cleaned out and the manifolds were ceramic coated this time in 2017.

New timing chain and gears both times

FelPro gasket sets. They have the better quality valve guide seals

I used the original oil pump in 2005 but with the 2017 problem i wrote about on this forum, I got a new pump for the 2017 rebuild. Thoroughly cleaned the pickup and it was fine.

I used all the original bolts in 2005 but got new rod ARP bolts, and a set of ARP main bearing studs and head studs for 2017. You have to have the rods "reconditioned" as well.

I went with the 1970 pulleys to completely eliminate the AIR pump nonsense. I put in a Delco 12SI based Powermaster 150 amp alternator - chrome of course.

I kept the original distributor in 2005 but it was too loose by 2017 so it was replaced. Still points & condenser and when it's running right, a cold start takes about 1/10 of a second.

I kept the 3 port thermal wax switch and have a couple spares as well.

I put in a Crane Cams adjustable vacuum advance kit in. They have them for both points and HEI ignitions.

AC copper plugs, you CANNOT run platinum plugs in a P&C ignition, New Delco 508D wire set.

If you want to keep your climate control, you have to run the factory intake and should run the proper QuadraJet. The Q-Jet is no slouch, when it's properly cleaned and set up. These were rated at 750CFM.

Get someone who knows what he is doing on the climate control R134 will work correctly if it is properly set up ans you can keep the original condenser and evaporate, just the POA / ST needs replacing along with a thorough flush. I had my lines stainless braided.

Get yourself about 5 cans of Hirsch Cadillac Dark Blue engine enamel for the painting.

Here's my engine just installed the day before I went on vacation:






« Last Edit: November 22, 2017, 08:06:26 PM by cadillacmike68 »
Regards,
"Cadillac" Mike
Current:
1968 DeVille Convertible
1996 Fleetwood Brougham
2009 STS NorthStar Platinum ed RWD
2011 CTS PRemiun ed Sedan RWD
Past:
2008 CTS Premium ed Sedan AWD
2005 CTS Hi-Feature Sedan RWD
2000 ElDorado ESC Hard Boot Convertible
1995 Fleetwood Brougham
1973 Sedan DeVille
1970 Fleetwood Brougham
1969 DeVille Convertible

Offline chrisntam

  • Posts: 1282
  • Dallas, Texas
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      CLC Member #29206
  • Name: C. Jessen
Re: Rebuilding a 472...
« Reply #13 on: November 22, 2017, 09:48:36 PM »
Engine looks great!

I'm ready to see Greg's write up on his ride in the Self Starter............

 ;)
1970 Deville Convertible  MTS 507
Dallas, Texas

Offline "Cadillac Kid" Greg Surfas 15364

  • Posts: 2815
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      CLC Member #15364
Re: Rebuilding a 472...
« Reply #14 on: November 22, 2017, 10:52:30 PM »
Working on it Chris.  Trying to get a couple of meaningful photos and captions.  It is kind of hard to condense a whole lot of activity down to 1500 words. Should be soon.
Greg Surfas
Cadillac Kid-Greg Surfas
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Online cadillacmike68

  • Posts: 1237
  • Still finishing up this 1968
    • CLC Member
      CLC Member #15823
  • Name: M Santos
Re: Rebuilding a 472...
« Reply #15 on: November 22, 2017, 11:34:01 PM »
Is 1,500 the max word limit on a submission? You can always go a bit over, because it WILL be edited.

I never wrote about my cars, i need to, at least the 1968 and 1996, and their predecessors.
Regards,
"Cadillac" Mike
Current:
1968 DeVille Convertible
1996 Fleetwood Brougham
2009 STS NorthStar Platinum ed RWD
2011 CTS PRemiun ed Sedan RWD
Past:
2008 CTS Premium ed Sedan AWD
2005 CTS Hi-Feature Sedan RWD
2000 ElDorado ESC Hard Boot Convertible
1995 Fleetwood Brougham
1973 Sedan DeVille
1970 Fleetwood Brougham
1969 DeVille Convertible

Offline Roger Zimmermann

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  • Switzerland
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  • Name: Roger Zimmermann
Re: Rebuilding a 472...
« Reply #16 on: November 23, 2017, 02:03:11 AM »
. The 68 472 had 10:1compression oe.  I could see going down to use regular, but something's  odd about that piston change.
Dave, don't forget that Nicholas is located in Switzerland and the cars GM imported at that time had low compression pistons.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham
1972 Coupe de Ville (not yet arrived)
2011 DTS
CLCMRC benefactor #101

Offline Bobby B

  • Posts: 1650
  • Mendham, New Jersey
  • Name: Bob Bender
Re: Rebuilding a 472...
« Reply #17 on: November 23, 2017, 09:52:30 AM »
Here's my engine just installed the day before I went on vacation:

Nice Job....... ;)
                 Bobby
1947 Cadillac Series 62 Convertible Coupe
1968 Mustang Convertible
1973 Mustang Convertible
1969 Jaguar E-Type Roadster
1971 Datsun 240Z
1979 H-D FLH

Offline Dave Shepherd

  • Posts: 1933
Re: Rebuilding a 472...
« Reply #18 on: November 23, 2017, 11:49:50 AM »
Nice Job....... ;)
                 Bobby
. Your are correct, missed that completely!! :-[

Offline Jeff Rose CLC #28373

  • Posts: 1434
  • Name: Jeff Rose
Re: Rebuilding a 472...
« Reply #19 on: November 23, 2017, 09:20:02 PM »
+1 on the engine-- Beautiful!
Have the shop actually measure the rockers and pedestals.
I had an issue with mine. They were made in the US and brand new but they each had so much slop they ticked like crazy. I chased my tail all over the place until I found it by accident. I am running the original set now and they are still better than the brand new crap the shop put in.http://forums.cadillaclasalleclub.org/index.php?topic=143600.msg351510#msg351510 
TJ is correct on the bolts. They put the wrong bolts my cam sprocket which caused the cam to move forward and back for the 10 seconds it ran before we shut it off. Find out as much as possible about the shop and who will be doing the work.  As it turns out the guy who built mine was sick at the end and I think he rushed to get it done. I had to get it out of there quickly before things turned messy when he got sick. He died shortly after I got the engine out so I really had no recourse with the problems I had. Not being cold hearted but just telling it like it is.
Good luck
Jeff
« Last Edit: November 23, 2017, 09:32:39 PM by Jeff Rose CLC #28373 »
Jeff
CLC #28373
1970 Coupe DeVille
1955 Series 62

 

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