I have heard these Caddy motors like to run hotter than the Chevys (this being by intentional design, not a flaw). I was told by more than one reputable source that 215 degrees is the "normal" temp for these things? Some of yall obviously know more about these than I do, so what do yall know? I wouldn't mind stuffing one into a future project... BTW, I had the opportunity to drive a 41 Caddy Sedanette running a 500 twisting a 2.47 geared rear thru a TH400. Torquey? Yes, very much so!!! I was amazed at what it would do in that big heavy car with super tall gears.
Sam.....my '75 Motors Manual gives me this info: 1973 Caddy 472........ 220 hp at 4000 rpm and 365 lb ft of torque at 2400 rpm. There's a notation saying all figures are "as installed in the car" which means the readings were recorded with all accessories installed, like A/C, 100 amp alternator, smog pump and Power steering pump. The compression ratio for 73 is 8.5 to one as opposed to the 1969 engine which has 10 to one, had no parasitic pumps or alternator during testing and records a 375 hp figure with a massive 525 [!] lb ft of torque! Tell me that baby won't ping on 85 octane..
Thanks Rocky! FWIW, Another reason that the earlier '70 motor makes more power is that SAE went to a "net" horsepower rating in 1972 or '73. Before that, the motors were being tested on a dynomometer without all their accesories... then, in '72 they began testing them with all the stuff bolted to the front (smog pump, water pump, AC compressor, alternator... all this stuff knocked the power down about 20%. So, that 375 hp motor in 72 made about 300hp. All motors had lower compression in '72 and '73... and then went drastically down hill from there. Thanks for all your help guys! This is a pretty cool thread. Sam.
Sam- the 4-6-8 that Plan9 was discussing was an engine that Cadillac offered in the Eighties that would shut down[thru valvetrain actuation] to run on 4 then on demand pick up to 6 cyls and when needed 8 cyls were functional......]PROBLEMS WERE COMMON WITH THOSE ENGINES.
Hi Sam- The higher compression 68-70 engines like premium for sure,and for towing are not as good as the later,lower compression ones.Your '73 has the same heads as the earlier engines but Cadillac dished the pistons to drop the compression.It's a good engine.It'll run on 87 octane in a truck as long as the cooling system is good and the distributor is set up right.With decent dual exhaust and a good tune it will make about 300 HP on an engine dyno,and a good flat torque curve from 1500-4500 rpm.A good radiator with an engine driven clutch fan and good shroud will keep it cool,and like mentioned above,the Caddys do tend to run a bit hotter by design-190-215 is normal. The Edelbrock intake will add a good 25 hp,and if you want to mess with making headers you can get that much more from them too. You know,a lot of these have been kinda neglected maintenance-wise,and it's always good to look closely at the oil suction screen for sludge and pieces of valve seal and timing gear.The true mid-sump pans came on 77-79 Devilles and Fleetwoods with the 425 engine.You can bolt it right on a 472 with the 425 suction tube and dipstick setup-need to dent the front part of the pan down about 1/4" to use it on a 500-the rods just touch if you forget. Chicken
Hi Sam! Damn I want one of dem fi' hunnerts for my Oldsmobuick. Here's a couple of links I've saved.. Cadillac Performance Board- http://www.hwforums.com/2089/ and a company that specializes in those engines called Cad Company http://www.cad500parts.com/ be sure and download their catalog. tell Nate hi. R
Nate says "tell him I said 'hi' too!" Here's the behemouth... What trannies fit it?? And where do I find the casting number to tell what it is? Sam.
Sam, I'm puttin a 472 and a Ford topaloder four speed with a jeep top shift conversion in my 51 F1. You can put a stick behind one. The crank in my motor has a big but shallow(just over 3/8 deep) in it. I just machined a press in oilite bearing for that hole. I got a steel billet flywheel (works with the stock starter comes drilled for Ford or GM pressure plates in 11" dia) & put a centerforce clutch on it. I used a BOP scattershield to bolt on the motor (I had to move the starter pocket on mine some have a starter pocket on both sides but the one I got was a freebe so I can't bitch). Then I had to shorten the input shaft and pilot bearing retainer just over an inch and re drill the scattershield for the Ford patten. None of which you have to do if you use a GM manual trans. If you want to go this route I can get you one of those flywheels for $260.00 just call me here at Streamline 1-800-426-5911. Hope this info is useful. Woody
Any BOP auto trans will fit motor. Manual bellhousing bolts up, no pilot bearing hole in crank though. Only the stroke on a 472/500 is different. Pull a plug, stick a screwdriver in there, mark TDC and BDC and measure marks. Just a tiny hair under 4 1/16", 472. 4 5/16", 500
Sam, I have a 425ci 78 Caddy motor in my 48 F-1. It replaced a 68 472 ci Cad that had a bad rap and finally siezed up. I have been extremely pleased with both engines. I originally ran the original differential with a 411 gear and now have a 290 gear in a 9" from a 72 pickup. I am using the 68 turbo 400 tranny with a mild shift kit. Maximum Torque Specialities (MTS) owner Al Betker has been extremely helpful to me. Check out their message board, www.hwforums.com and the MTS home page. www.500cid.com. On these sites you will find a ton of info on using the big block Caddy for towing. If I am not mistaken, Al even offers a kit for mounting one these engines in a Chevy pickup. After years of playing with small blocks these motors are king even in stock form. This 48 F-1 with either motor is a better performing truck than a 47 ford pickup I had with a 327ci Hi-Performance Vette motor. I think you'll enjoy the Caddy. Bill
hey sam, choprods explained the 4-6-8 engines... they are junk, but the pans are rear sump and common. i believe the 368 came in 80-81 el dorados and sevilles. its a single drain plug, 5 quart pan... you have to use the rear dipstick tube hole. Transmissions - any GM/B.O.P. (buick olds & pontiac) tranny will work as they have the same bolt pattern. only time youll need an adapter plate is if you use one of the OD chevy transmissions, (and its said a big cadi motor will shred it to pieces). head #'s should be the same as chevy, located in the rocker arm valley(?) block #'s i *think, its been awhile* are located in the front near or rear, same as chevy... post the numbers when you get the chance and ill look em up. the 472/500 blocks are ALL high quality, and most heads, especially for towing are perfect.... however, heads off a '70 (950 casting #) are the most desireable the book i have covers EVERYTHING... even flex plates are covered. im heading up north tommorow for sure... ill bring it with me. you gonna be around this weekend? still havent talked to Terry about my arrival, things have been really hectic around here and ive been delayed 6 days already. poor me!!
boy that picture brings back memories.if i had enough dough id be into both oldsmobiles,and caddies.i love em.i thought the older ones didnt have air pumps though?maybe im wrong.i can see your holes in the heads where the tubes go in.it looks like you have hei too.thats a plus.the one in my 72 coupe went like hell for a big boat. eric
Man, I miss my two 500's. Got a complete 76 Eldo for $140, and some time later picked up a 75 Sedan engine for $100. That sedan motor only had 5000 miles on it, and still had the hatch marks in the bores. Fantastic motors. All you guys keep raving about them, you'll drive the prices up into the SBC range!
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