394 engine question
Thread Starter
Registered User
Joined: Feb 2020
Posts: 13
394 engine question
Hi Folks,
I have recently acquired a 50Olds/88 that has a 394 stuffed into it. I don't know much about this engine and trying to identify exactly what 394 it is. I believe it may be a 62 but not sure which one.
Wondering if anyone out there can help. I know this engine has been worked on and who knows what changes were made to it. Interestingly, the engine number on my heads and block is 15339, which is no where close to other numbers I have seen. No letters either except the right head does have a G in the second part of the number. If you have any ideas, they are welcome. The heads and engine match and a resource book also shows the other head numbers. I think it is a 62, only by comparing the various numbers of all of the parts. Here are the identifying numbers. Thanks, Rustednutz
Engine block 15339 stamped on left front of block, and it matches the heads number.
Engine block 582813 cast on flat spot behind distributor. American V-8 Engine Data Book shows this number for Olds 394 blocks 59-63.
Heads are stamped below edge of valve covers, middle of head above exhaust on flat spot -- Left head is 15339, Right head is 15339 G405194S. There are no other letters.
Both heads have 583832 cast under the valve cover in small numbers. This number is listed as a 59-63 year number for Olds 394 in the American V-8 Engine Data Book.
Left exhaust manifold has 5487193-2 cast. Right exhaust manifold has GM 579279 LH *D2 cast. The same Data book shows 579279 for the left side and 579278 on the right for 61-62.
Not sure what this means and how accurate the Data book is.
4 barrel Inase manifold cast number is 580677. Not sure if this is original intake or put on later.
The cast iron Flex-plate housing has 558709 1 *CFD cast on right front of housing.
Bore is 4 1/8
The oil pan has the protrusion on the right side, similar to the size of an oil filter. I have the pan off and I have no idea what that is for.
This engine has been rebuilt and repainted. Stamp on top of pistons is .040.
I have recently acquired a 50Olds/88 that has a 394 stuffed into it. I don't know much about this engine and trying to identify exactly what 394 it is. I believe it may be a 62 but not sure which one.
Wondering if anyone out there can help. I know this engine has been worked on and who knows what changes were made to it. Interestingly, the engine number on my heads and block is 15339, which is no where close to other numbers I have seen. No letters either except the right head does have a G in the second part of the number. If you have any ideas, they are welcome. The heads and engine match and a resource book also shows the other head numbers. I think it is a 62, only by comparing the various numbers of all of the parts. Here are the identifying numbers. Thanks, Rustednutz
Engine block 15339 stamped on left front of block, and it matches the heads number.
Engine block 582813 cast on flat spot behind distributor. American V-8 Engine Data Book shows this number for Olds 394 blocks 59-63.
Heads are stamped below edge of valve covers, middle of head above exhaust on flat spot -- Left head is 15339, Right head is 15339 G405194S. There are no other letters.
Both heads have 583832 cast under the valve cover in small numbers. This number is listed as a 59-63 year number for Olds 394 in the American V-8 Engine Data Book.
Left exhaust manifold has 5487193-2 cast. Right exhaust manifold has GM 579279 LH *D2 cast. The same Data book shows 579279 for the left side and 579278 on the right for 61-62.
Not sure what this means and how accurate the Data book is.
4 barrel Inase manifold cast number is 580677. Not sure if this is original intake or put on later.
The cast iron Flex-plate housing has 558709 1 *CFD cast on right front of housing.
Bore is 4 1/8
The oil pan has the protrusion on the right side, similar to the size of an oil filter. I have the pan off and I have no idea what that is for.
This engine has been rebuilt and repainted. Stamp on top of pistons is .040.
Registered User
Joined: Sep 2017
Posts: 5,171
From: St. Paul Minnesota
Hi Folks, I have recently acquired a 50Olds/88 that has a 394 stuffed into it. I don't know much about this engine and trying to identify exactly what 394 it is. I believe it may be a 62 but not sure which one.
The early Olds cars had later engines transplanted in them by "hot rodders". The 1957-58 J-2s and the 394's were the most popular. The 135 HP 303 with another engine increased horsepower to 312 or more. What transmission are you using?
Wondering if anyone out there can help. I know this engine has been worked on and who knows what changes were made to it. Interestingly, the engine number on my heads and block is 15339, which is no where close to other numbers I have seen. No letters either except the right head does have a G in the second part of the number. If you have any ideas, they are welcome. The heads and engine match and a resource book also shows the other head numbers. I think it is a 62, only by comparing the various numbers of all of the parts. Here are the identifying numbers. Thanks, Rustednutz
Charlie Jones and others on here will probably chime in with more facts. The 394 was manufactured from 1959-64. I believe the cylinder heads were cast with a two digit number also. 1959 heads were probably #18's and changed to #21 through the years, Charlie will correct me on this. I think the later heads flowed a little better.
Engine block 15339 stamped on left front of block, and it matches the heads number.
Engine block 582813 cast on flat spot behind distributor. American V-8 Engine Data Book shows this number for Olds 394 blocks 59-63.
Heads are stamped below edge of valve covers, middle of head above exhaust on flat spot -- Left head is 15339, Right head is 15339 G405194S. There are no other letters.
Both heads have 583832 cast under the valve cover in small numbers. This number is listed as a 59-63 year number for Olds 394 in the American V-8 Engine Data Book.
Left exhaust manifold has 5487193-2 cast. Right exhaust manifold has GM 579279 LH *D2 cast. The same Data book shows 579279 for the left side and 579278 on the right for 61-62.
Not sure what this means and how accurate the Data book is.
4 barrel Intake manifold cast number is 580677. Not sure if this is original intake or put on later.
The cast iron Flex-plate housing has 558709 1 *CFD cast on right front of housing.
Bore is 4 1/8
4 1/8 would make it a 394. There was a casting that just had the 4, that was a 371.
The oil pan has the protrusion on the right side, similar to the size of an oil filter. I have the pan off and I have no idea what that is for.
This engine has been rebuilt and repainted. Stamp on top of pistons is .040.
The early Olds cars had later engines transplanted in them by "hot rodders". The 1957-58 J-2s and the 394's were the most popular. The 135 HP 303 with another engine increased horsepower to 312 or more. What transmission are you using?
Wondering if anyone out there can help. I know this engine has been worked on and who knows what changes were made to it. Interestingly, the engine number on my heads and block is 15339, which is no where close to other numbers I have seen. No letters either except the right head does have a G in the second part of the number. If you have any ideas, they are welcome. The heads and engine match and a resource book also shows the other head numbers. I think it is a 62, only by comparing the various numbers of all of the parts. Here are the identifying numbers. Thanks, Rustednutz
Charlie Jones and others on here will probably chime in with more facts. The 394 was manufactured from 1959-64. I believe the cylinder heads were cast with a two digit number also. 1959 heads were probably #18's and changed to #21 through the years, Charlie will correct me on this. I think the later heads flowed a little better.
Engine block 15339 stamped on left front of block, and it matches the heads number.
Engine block 582813 cast on flat spot behind distributor. American V-8 Engine Data Book shows this number for Olds 394 blocks 59-63.
Heads are stamped below edge of valve covers, middle of head above exhaust on flat spot -- Left head is 15339, Right head is 15339 G405194S. There are no other letters.
Both heads have 583832 cast under the valve cover in small numbers. This number is listed as a 59-63 year number for Olds 394 in the American V-8 Engine Data Book.
Left exhaust manifold has 5487193-2 cast. Right exhaust manifold has GM 579279 LH *D2 cast. The same Data book shows 579279 for the left side and 579278 on the right for 61-62.
Not sure what this means and how accurate the Data book is.
4 barrel Intake manifold cast number is 580677. Not sure if this is original intake or put on later.
The cast iron Flex-plate housing has 558709 1 *CFD cast on right front of housing.
Bore is 4 1/8
4 1/8 would make it a 394. There was a casting that just had the 4, that was a 371.
The oil pan has the protrusion on the right side, similar to the size of an oil filter. I have the pan off and I have no idea what that is for.
This engine has been rebuilt and repainted. Stamp on top of pistons is .040.
Phantom Phixer
Joined: Dec 2011
Posts: 5,497
From: Apopka, FL
You were right in assuming it is a 1962 engine .
The 1962 Oldsmobile Service Manual identifies the number G405194S as a 1962 Starfire ( 345 HP ) engine .
The data book you have is riddeled with inaccuracys .
The block casting # 582813 is a 1961 or 62 block with a cast iron timing cover . 63 & 64 had an aluminum timing cover with # 585786.
Your data book shows 59-63 .
The head casting numbers 583832 were used in 61 Starfires and all 62 thru 64 394's .
The exhaust manifold number 5487193 makes no sense , should be a six digit number .
The number 579279 is for a 61 or 62 394 .
The intake # 580677 is for a 59 thru 62 394 .
This engine originally had unpolished chrome valve covers , and was painted red .
BTW , the Starfire engine was only different in the pistons ( more compression ) , the camshaft ( more duration ) and chrome valve covers ,from all other 394's .
The extra " can" welded to the side of the oil pan was added to the pan to increase oil capacity .
57 thru 62's had this style pan . In 1963 the pan was re-designed without it and was made larger .
The 1962 Oldsmobile Service Manual identifies the number G405194S as a 1962 Starfire ( 345 HP ) engine .
The data book you have is riddeled with inaccuracys .
The block casting # 582813 is a 1961 or 62 block with a cast iron timing cover . 63 & 64 had an aluminum timing cover with # 585786.
Your data book shows 59-63 .
The head casting numbers 583832 were used in 61 Starfires and all 62 thru 64 394's .
The exhaust manifold number 5487193 makes no sense , should be a six digit number .
The number 579279 is for a 61 or 62 394 .
The intake # 580677 is for a 59 thru 62 394 .
This engine originally had unpolished chrome valve covers , and was painted red .
BTW , the Starfire engine was only different in the pistons ( more compression ) , the camshaft ( more duration ) and chrome valve covers ,from all other 394's .
The extra " can" welded to the side of the oil pan was added to the pan to increase oil capacity .
57 thru 62's had this style pan . In 1963 the pan was re-designed without it and was made larger .
Last edited by Charlie Jones; Feb 17, 2020 at 12:14 PM.
Registered User
Joined: Sep 2006
Posts: 1,142
That cylinder head number is for a 1962 Starfire. As far as the pan, it is the stock oil pan. Don’t let anybody else tell you it’s for ‘extra capacity’.
Thread
Thread Starter
Forum
Replies
Last Post
