Cadillac engine knowledge

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[[Image:Cadsuburban.jpg|frame|A Cadillac engine in an early Suburban]]
 
[[Image:Cadsuburban.jpg|frame|A Cadillac engine in an early Suburban]]
 
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==General specifications==
==Basic engine specifications==
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===General specifications===
 
 
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! Year !! Disp. !! Fuel !! Horsepower !! Torque@RPM !! Bore x Stroke !! Comp. ratio
 
! Year !! Disp. !! Fuel !! Horsepower !! Torque@RPM !! Bore x Stroke !! Comp. ratio
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The stock cam can benefit from advancing the cam timing 2 degrees, as these engines had retarded cam timing in stock form for emissions. Attach the degree wheel to the crank with a 9/16-24 fine thread bolt.
 
The stock cam can benefit from advancing the cam timing 2 degrees, as these engines had retarded cam timing in stock form for emissions. Attach the degree wheel to the crank with a 9/16-24 fine thread bolt.
  
===Transmissions===
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==Transmissions==
  
*'''TH350'''
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===TH350===
  
 
Some TH350 transmissions came with steel transmission cases in older military tanks and trucks; they would be best for mondo horsepower applications such as 1500+ hp cad engines. It's fairly easy to build a 2000 hp twin turbo Cad with 35 pounds of boost at 7:1 compression on alcohol. It's said the block can take it, but the cast crank might not be able to.
 
Some TH350 transmissions came with steel transmission cases in older military tanks and trucks; they would be best for mondo horsepower applications such as 1500+ hp cad engines. It's fairly easy to build a 2000 hp twin turbo Cad with 35 pounds of boost at 7:1 compression on alcohol. It's said the block can take it, but the cast crank might not be able to.
  
*'''TH400'''
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===TH400===
  
 
The basic 472 and the later 500 engines both use a Buick/Pontiac/Olds/Cadillac (BOPC) bell housing bolt pattern, so a TH400 automatic will bolt right up to the back of the block as long as the proper Cadillac flexplate and torque converter are used. The TH425 front-drive automatic transaxle also fits these engines as used in the Eldorado, although a special dual-sump oil pan and pickup are used with these transmissions due to the required half shaft clearance. Any RWD engine can be converted to FWD and vice versa if the proper oil pan and pickup are used, although two of the main cap bolts must be removed and swapped for studs with standoffs to mount the pickup bracket. Another good thing about these engines using a TH400 transmission is that a BOPC patterned case can be assembled with the Chevy 4x4 tailshaft and associated hardware for use in an off-road truck. The engine weight is approximately 600 pounds fully dressed and splits the difference between small and big block Chevy, so suspension modifications are not usually necessary. Transfer case choice for a 4x4 should be a NP205, as fitted to some mid/late 1970's Chevy 1 ton trucks. The NP205 is a strong gear-driven transfer case and holds up nicely to the big Caddy's torque output.
 
The basic 472 and the later 500 engines both use a Buick/Pontiac/Olds/Cadillac (BOPC) bell housing bolt pattern, so a TH400 automatic will bolt right up to the back of the block as long as the proper Cadillac flexplate and torque converter are used. The TH425 front-drive automatic transaxle also fits these engines as used in the Eldorado, although a special dual-sump oil pan and pickup are used with these transmissions due to the required half shaft clearance. Any RWD engine can be converted to FWD and vice versa if the proper oil pan and pickup are used, although two of the main cap bolts must be removed and swapped for studs with standoffs to mount the pickup bracket. Another good thing about these engines using a TH400 transmission is that a BOPC patterned case can be assembled with the Chevy 4x4 tailshaft and associated hardware for use in an off-road truck. The engine weight is approximately 600 pounds fully dressed and splits the difference between small and big block Chevy, so suspension modifications are not usually necessary. Transfer case choice for a 4x4 should be a NP205, as fitted to some mid/late 1970's Chevy 1 ton trucks. The NP205 is a strong gear-driven transfer case and holds up nicely to the big Caddy's torque output.
  
*'''700R4/4L60/4L80E'''
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===700R4/4L60/4L80E'===
  
 
The 700R4/4L60/4L80E can be a good transmission to use on the Cadillac 472 and 500, due to the fact that you can run 4.11 gears and not over rev the engine with the over drive 4th gear.  
 
The 700R4/4L60/4L80E can be a good transmission to use on the Cadillac 472 and 500, due to the fact that you can run 4.11 gears and not over rev the engine with the over drive 4th gear.  
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More [https://www.hgmelectronics.com/download/attachments/8913147/Chevy+High+Performance+-+Dec+2011.pdf?version=1&modificationDate=1324542463096 over drive automatic transmission controllers] from ''Chevy High Performance'' December 2011.
 
More [https://www.hgmelectronics.com/download/attachments/8913147/Chevy+High+Performance+-+Dec+2011.pdf?version=1&modificationDate=1324542463096 over drive automatic transmission controllers] from ''Chevy High Performance'' December 2011.
  
===Engine mounting===
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==Engine mounting==
 
When bolting these engines into most any application, use the stock-type Cadillac Eldorado engine mounts, oil pan and associated pickup tube. Fabricate a set of 3/8 inch thick plates to be bolted between the crossmember. The big Cad has the mount bolts 3-1/2 inches ahead of where the Chevy mounts are when measuring from the stock Chevy engine to transmission bellhousing mating surface.  
 
When bolting these engines into most any application, use the stock-type Cadillac Eldorado engine mounts, oil pan and associated pickup tube. Fabricate a set of 3/8 inch thick plates to be bolted between the crossmember. The big Cad has the mount bolts 3-1/2 inches ahead of where the Chevy mounts are when measuring from the stock Chevy engine to transmission bellhousing mating surface.  
  
 
For a 4x4 truck, the engine usually fits well by using crossmember and frame rail notches to clear the oil pump. If the truck originally used a TH350 transmission, the crossmember needs to go back about 3 inches and custom drive shafts will needed. These should use the larger 1 ton U-joints for added durability.
 
For a 4x4 truck, the engine usually fits well by using crossmember and frame rail notches to clear the oil pump. If the truck originally used a TH350 transmission, the crossmember needs to go back about 3 inches and custom drive shafts will needed. These should use the larger 1 ton U-joints for added durability.
  
===Oil pumps===
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==Oil pumps==
 
There are different oil pumps for the big Cadillac engines. One faces forward from the block at a 45 degree angle downward. The next faces downward 45 degrees and points right toward the bottom of the crankshaft pulley. There is another, that has been described as pointing more outward than the first one described. These can all be interchanged, but make very sure to properly clean the oil pump and block mating surfaces and always use a new oil pump gasket. The correct gaskets are available from major gasket manufacturers, and should be about 0.005" thick. An oil pump gasket that is too thick will cause more oil to bypass the pump gears and allow more end play of those gears too, something you do not want.
 
There are different oil pumps for the big Cadillac engines. One faces forward from the block at a 45 degree angle downward. The next faces downward 45 degrees and points right toward the bottom of the crankshaft pulley. There is another, that has been described as pointing more outward than the first one described. These can all be interchanged, but make very sure to properly clean the oil pump and block mating surfaces and always use a new oil pump gasket. The correct gaskets are available from major gasket manufacturers, and should be about 0.005" thick. An oil pump gasket that is too thick will cause more oil to bypass the pump gears and allow more end play of those gears too, something you do not want.
  
 
The stock Cad oil pump spring can be shimmed using a Q-jet metering jet to boost oil pressure to about 50-60 psi. 10-12 psi per 1000 rpm is good. Make sure to prime the oiling system using an electric drill to spin the pump after you do this to check for proper operation of the pump and pressure bypass and to check the oil pressure psi.  
 
The stock Cad oil pump spring can be shimmed using a Q-jet metering jet to boost oil pressure to about 50-60 psi. 10-12 psi per 1000 rpm is good. Make sure to prime the oiling system using an electric drill to spin the pump after you do this to check for proper operation of the pump and pressure bypass and to check the oil pressure psi.  
  
===Oil Pans===
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==Oil Pans==
 
RWD pans used a front-sump pan and pickup. The Eldorado used a rear-sump setup. Later 425 and 368 engines used a mid-sump style. The latter two pans are what you would typically use for most engine swaps.
 
RWD pans used a front-sump pan and pickup. The Eldorado used a rear-sump setup. Later 425 and 368 engines used a mid-sump style. The latter two pans are what you would typically use for most engine swaps.
  
 
If possible, use the front sump oil pan design to eliminate the longer pickup; this will help keep the engine primed instead of using a thicker motor oil.  
 
If possible, use the front sump oil pan design to eliminate the longer pickup; this will help keep the engine primed instead of using a thicker motor oil.  
  
===Clearance issues===
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==Clearance issues==
 
In cars the clearance problems are usually at the front crossmember, the driver side exhaust manifold, and possibly the HVAC airbox on the firewall. This can be modified with fiberglass or sheetmetal if necessary. Streetrods usually have sufficient room to drop the big Cad engine in. The fit is tight like with a big block Chevy, but the only change usually required will be in motor mount placement. Most all vehicles requiring a rear-sump oil pan and pickup can use the Eldorado pan and pickup tube, or a mid-sump pan and pickup as found on the smaller 368-425 Cadillac engines of 1977-'79 vintage. Stock exhaust manifolds may be used, or aftermarket block-hugger style headers can be sourced from Sanderson. In most cases where a big block Chevy header can be used, the Chevy flanges can be removed and Cad flanges can be made up quite easily. The primary tubes may need a bit of tweaking to line up with the ports with this method. Remember that the front and rear drive exhaust manifolds are different for the driver side. This may help in routing the exhaust if it is a tight fit on that side.
 
In cars the clearance problems are usually at the front crossmember, the driver side exhaust manifold, and possibly the HVAC airbox on the firewall. This can be modified with fiberglass or sheetmetal if necessary. Streetrods usually have sufficient room to drop the big Cad engine in. The fit is tight like with a big block Chevy, but the only change usually required will be in motor mount placement. Most all vehicles requiring a rear-sump oil pan and pickup can use the Eldorado pan and pickup tube, or a mid-sump pan and pickup as found on the smaller 368-425 Cadillac engines of 1977-'79 vintage. Stock exhaust manifolds may be used, or aftermarket block-hugger style headers can be sourced from Sanderson. In most cases where a big block Chevy header can be used, the Chevy flanges can be removed and Cad flanges can be made up quite easily. The primary tubes may need a bit of tweaking to line up with the ports with this method. Remember that the front and rear drive exhaust manifolds are different for the driver side. This may help in routing the exhaust if it is a tight fit on that side.
  
 
The Cad engines do not fit easily in some GM chassis. Never fit the engine in without putting the exhaust manifold on first. Better yet, use a custom set of block hugger headers, as Cad parts are usually insanely expensive (but worth it in this case).
 
The Cad engines do not fit easily in some GM chassis. Never fit the engine in without putting the exhaust manifold on first. Better yet, use a custom set of block hugger headers, as Cad parts are usually insanely expensive (but worth it in this case).
  
===Intake manifold===
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==Intake manifold==
 
Stock carbureted intake manifolds can benefit from a 1 inch spacer under the carburetor, adding around 15 hp. Because of the bathtub-type steel intake gasket, plate stock and exhaust tubing can be fabricated into a tunnel ram style dual carb manifold. You can build one of these to use a pair of Quadrajets from 4.1L Buick V6 or 4.3L Chevy V6 engines, as two of these with straight linkage could feed the big motor quite well. The bathtub gasket can be reused by using a bit of Permatex to seal the block and head surfaces by encircling the ports to prevent an internal vacuum leak on both sides of the gasket.
 
Stock carbureted intake manifolds can benefit from a 1 inch spacer under the carburetor, adding around 15 hp. Because of the bathtub-type steel intake gasket, plate stock and exhaust tubing can be fabricated into a tunnel ram style dual carb manifold. You can build one of these to use a pair of Quadrajets from 4.1L Buick V6 or 4.3L Chevy V6 engines, as two of these with straight linkage could feed the big motor quite well. The bathtub gasket can be reused by using a bit of Permatex to seal the block and head surfaces by encircling the ports to prevent an internal vacuum leak on both sides of the gasket.
  
 
===EFI===
 
===EFI===
[[File:Cad efi.jpg‎ ]]
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[[File:Cad efi.jpg|left|400px]]
 
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The factory EFI system used from 1975-'76 on 500 cubic inch engines is a ported injection system which operates similar to the familiar Chevy TPI. It looks like a large throttle body on an intake with separate fuel injectors. Each cylinder has its own injector mounted in the intake runner near the intake gasket area with a common fuel rail feeding all eight injectors. This system was also used through 1979 on the Seville as standard equipment and as an option on full size cars.  
 
The factory EFI system used from 1975-'76 on 500 cubic inch engines is a ported injection system which operates similar to the familiar Chevy TPI. It looks like a large throttle body on an intake with separate fuel injectors. Each cylinder has its own injector mounted in the intake runner near the intake gasket area with a common fuel rail feeding all eight injectors. This system was also used through 1979 on the Seville as standard equipment and as an option on full size cars.  
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==Exhaust==
 
==Exhaust==
  
[[image:BBC_headers_next_to_Cad_exhaust_ports.jpg|frame|BBC headers/Cad engine]]
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[[image:BBC_headers_next_to_Cad_exhaust_ports.jpg|thumb|left|500px|BBC headers/Cad engine]]
 
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==Cadillac engine parts sources==
 
==Cadillac engine parts sources==

Revision as of 02:47, 12 March 2012

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