Cadillac engine knowledge
| Line 1: | Line 1: | ||
| − | {{ | + | {{develop}} |
[[Image:Cadsuburban.jpg|frame|A Cadillac engine in an early Suburban]] | [[Image:Cadsuburban.jpg|frame|A Cadillac engine in an early Suburban]] | ||
| − | |||
==Basic engine specifications== | ==Basic engine specifications== | ||
===Tune-up specifications=== | ===Tune-up specifications=== | ||
| − | |||
Year--Disp.-Fuel-Sparkplugs-Dist.-Timing BTDC-Intake opens-Idle speed | Year--Disp.-Fuel-Sparkplugs-Dist.-Timing BTDC-Intake opens-Idle speed | ||
| Line 28: | Line 26: | ||
'75-76...500...4bbl...R45NSXgap@.060...HEI...6B...21B...600 | '75-76...500...4bbl...R45NSXgap@.060...HEI...6B...21B...600 | ||
| − | '75-76...500...EFI...R45NSXgap@.060...HEI...12B...21B...600 | + | '75-76...500...EFI...R45NSXgap@.060...HEI...12B...21B...600 |
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| + | ===General specifications:=== | ||
Year-Disp.-Fuel-Horsepower-Torque@RPM-BorexStroke-Comp. ratio | Year-Disp.-Fuel-Horsepower-Torque@RPM-BorexStroke-Comp. ratio | ||
| Line 63: | Line 57: | ||
| − | + | ===Fastener torque specifications=== | |
| − | + | ||
| − | + | ||
| − | ===Fastener | + | |
| − | + | ||
Year-Disp.-Head-Rod-Main-Crank damper-Flywheel-Intake-Exhaust | Year-Disp.-Head-Rod-Main-Crank damper-Flywheel-Intake-Exhaust | ||
| Line 73: | Line 63: | ||
| − | ==Identification | + | ==Identification== |
| − | + | ||
'68-'69 472: 1486238 | '68-'69 472: 1486238 | ||
| Line 84: | Line 73: | ||
| − | ===Crank | + | ===Crank casting number=== |
| − | + | ||
'68-'74 472: 1486424 | '68-'74 472: 1486424 | ||
| Line 98: | Line 86: | ||
===Stroke:=== | ===Stroke:=== | ||
| − | + | (Stroke can be measured through spark plug hole if it will turn.) | |
| − | + | ||
'68-'74 472, 77-'79 425, '80-'85 368: 4.060" (less than 4 1/8") | '68-'74 472, 77-'79 425, '80-'85 368: 4.060" (less than 4 1/8") | ||
| Line 106: | Line 93: | ||
| − | ===Head | + | ===Head casting number=== |
| − | + | (Usually in the center of the head under the valve cover.) | |
'68-'69 472: 1486250 | '68-'69 472: 1486250 | ||
| Line 121: | Line 108: | ||
'77-'79 425: 1609112, 1609423 (last 3 usually on driver's front / pass. rear exhaust port) | '77-'79 425: 1609112, 1609423 (last 3 usually on driver's front / pass. rear exhaust port) | ||
| − | '80-'85 368: 1615188, others | + | '80-'85 368: 1615188, others unknown. The 4-6-8 head is substantially different than the regular head, and the rocker assemblies are not directly interchangeable. |
| + | A fairly comprehensive 2 page PDF ID guide with pictures can be found here (mostly about the 472/500 stuff): http://www.cad500parts.com/tech/EngineIDPages.pdf. For Quick ID - on the second page, there is a box shape shown on the rear of the '77-later blocks to ID the smaller engines. Distinguishing a '70-newer 472 from a 500 can only be done by crank number, stroke, or piston design, as all other parts are the same. | ||
| − | |||
| − | + | ==Modifications and swapping== | |
| − | + | ||
| − | + | ||
| − | ==Modifications and | + | |
The biggest gains in power output come with cylinder head work. Pre-'74 heads are small chamber 76 cc's and are good for around 12 to 1 compression with race gas. The '74 and later heads have larger 120 cc chambers and are a better choice for a pump gas torquer with an 8.5 to 1 compression ratio. The best bet for a pump gas premium street torque monster is a set of '77-'79 425 heads. These offer an honest 10:1 compression ratio on both 472 and 500 engines. Big gains can be made by adding larger valves and induction hardened seats. The valve sizes can be boosted to 2.08"/1.70" without worry of hitting the water jackets. The usual porting, valve unshrouding and minor bowl modifications will work, although the short-side radius should be left alone to avoid drastic differences in airflow. Roughly 20 horses can be gained by this work alone and most of that comes from the larger valves. | The biggest gains in power output come with cylinder head work. Pre-'74 heads are small chamber 76 cc's and are good for around 12 to 1 compression with race gas. The '74 and later heads have larger 120 cc chambers and are a better choice for a pump gas torquer with an 8.5 to 1 compression ratio. The best bet for a pump gas premium street torque monster is a set of '77-'79 425 heads. These offer an honest 10:1 compression ratio on both 472 and 500 engines. Big gains can be made by adding larger valves and induction hardened seats. The valve sizes can be boosted to 2.08"/1.70" without worry of hitting the water jackets. The usual porting, valve unshrouding and minor bowl modifications will work, although the short-side radius should be left alone to avoid drastic differences in airflow. Roughly 20 horses can be gained by this work alone and most of that comes from the larger valves. | ||
| − | Blocks should get the standard deburring. A drain hole can be drilled into the rear of the lifter valley for better oil drainback and a spillway can be added to the oval hole at the front of the block to better lubricate the timing chain and the camshaft thrust face. Incidentally, a later block has 1/2 inch oil galleries for increased flow through the block, so it makes a good performance base. If the front cover has [[rust]] pitting from the water pump, it can be saved by sandblasting and filling the pits with JB Weld and then painting. One more thing about blocks, a 472 can be made into a 500 by swapping in the 500 crank and pistons, although on '68-69 engines, a slight amount of notching is necessary at the bottom of the cylinder bores. | + | Blocks should get the standard deburring. A drain hole can be drilled into the rear of the lifter valley for better oil drainback and a spillway can be added to the oval hole at the front of the block to better lubricate the timing chain and the camshaft thrust face. Incidentally, a later block has 1/2 inch oil galleries for increased flow through the block, so it makes a good performance base. If the front cover has [[rust]] pitting from the water pump, it can be saved by [[sandblasting]] and filling the [[Pitted rust|pits]] with JB Weld and then painting. One more thing about blocks, a 472 can be made into a 500 by swapping in the 500 crank and pistons, although on '68-69 engines, a slight amount of notching is necessary at the bottom of the cylinder bores. |
| − | + | ||
| − | + | ||
| − | + | ||
| − | High | + | ===High performance tolerances=== |
Crank endplay- minimum .008 | Crank endplay- minimum .008 | ||
| Line 147: | Line 128: | ||
Second ring- .018 | Second ring- .018 | ||
| − | + | ==MIscellaneous== | |
| − | + | ||
| − | + | ||
Cam degreeing benefits from advancing the cam timing 2 degrees, as these engines had a retarded cam in stock form for emissions. Attach the degree wheel to the crank with a 9/16 fine thread bolt. | Cam degreeing benefits from advancing the cam timing 2 degrees, as these engines had a retarded cam in stock form for emissions. Attach the degree wheel to the crank with a 9/16 fine thread bolt. | ||
| Line 166: | Line 145: | ||
Point-type distributors are similar to the familiar Chevy and use the same internal parts, however the internal shaft and the housing are Cadillac only. Ignition parts for the HEI-style distributors are also the same as the Chevy engine uses, with a few exceptions. First, like the points distributor, the shaft and housing are Cadillac only. Also, the distributor will differ between carbureted and fuel injected engines. The fuel injected distributor has a position sensor under the main body that tells the computer the engine speed and when to trigger the proper injectors. If you're not sure what distributor you have, the carbureted version looks the same as the Chevy, and the fuel injected has a square portion with a round 3 pin plug directly above the clamp area. Finally, the hold-down clamp used will depend on the distributor. They don't interchange, so get the clamp when you get the distributor. Best choice for ignition wires would be a cut-to-fit set, as even the stockers do not fit quite the way they should due to the front-mounted distributor location. | Point-type distributors are similar to the familiar Chevy and use the same internal parts, however the internal shaft and the housing are Cadillac only. Ignition parts for the HEI-style distributors are also the same as the Chevy engine uses, with a few exceptions. First, like the points distributor, the shaft and housing are Cadillac only. Also, the distributor will differ between carbureted and fuel injected engines. The fuel injected distributor has a position sensor under the main body that tells the computer the engine speed and when to trigger the proper injectors. If you're not sure what distributor you have, the carbureted version looks the same as the Chevy, and the fuel injected has a square portion with a round 3 pin plug directly above the clamp area. Finally, the hold-down clamp used will depend on the distributor. They don't interchange, so get the clamp when you get the distributor. Best choice for ignition wires would be a cut-to-fit set, as even the stockers do not fit quite the way they should due to the front-mounted distributor location. | ||
| − | + | ==Cadillac engine parts sources:== | |
| − | + | [http://www.cad500parts.com/ Cad Company] | |
| − | == | + | [http://www.500cid.com/ Maximum Torque Specialties] |
| − | + | ||
| − | + | ||
{{youcanedit}} | {{youcanedit}} | ||
Your Privacy Choices