1961 engine code
Thread Starter
8th Gear
Joined: Nov 2008
Posts: 8
Likes: 0
1961 engine code
A friend of mine who has become disable has a 1961 corvette with 55,000 original miles on it. I am helping him to get the car ready to sell and we are trying to id the number on the 283 engine to make sure it is original. The number on the right front of the engine is FIIOIEB and right below that number is 1004. Normally the numbers are in line from what we have seen. It has the chrome air cleaner and aluminum valve covers with a holly carb on it. My friend has had the car since 1975 when he bought it from the second owner. Any help would be appreciated.
Jim and Ken
Jim and Ken
Melting Slicks
Joined: Jul 2004
Posts: 2,867
Likes: 195
From: Maryland
Depending on the DOB the casting # on the block should be either 3756519 or late DOB 3789935. This #s is found on the rear flange driver side . The engine pad code EB is NOT a Corvette code. Should start with C or D depending on trans. Also an original Corvette engine for 61 would have a 6 digit VIN derivative on the left side on the engine pad.
Thread Starter
8th Gear
Joined: Nov 2008
Posts: 8
Likes: 0
Depending on the DOB the casting # on the block should be either 3756519 or late DOB 3789935. This #s is found on the rear flange driver side . The engine pad code EB is NOT a Corvette code. Should start with C or D depending on trans. Also an original Corvette engine for 61 would have a 6 digit VIN derivative on the left side on the engine pad.
ALL THE ENGINE PAD CODES THAT WE CHECKED HAD THE NUMBER ON THE LEFT SIDE OF THE FIIOIIEB NUMBER.
BUT THIS ENGINE DIDN'T.
COULD IT BE AN AFTER MARKET OR REPLACED ENGINE FROM THE FACTORY?
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
thanks I'll check the DOD #, IS THIS NUMBER ON THE BLOCK OR THE HEAD ON THE REAR FLANGE?
ALL THE ENGINE PAD CODES THAT WE CHECKED HAD THE NUMBER ON THE LEFT SIDE OF THE FIIOIIEB NUMBER.
BUT THIS ENGINE DIDN'T.
COULD IT BE AN AFTER MARKET OR REPLACED ENGINE FROM THE FACTORY?
ALL THE ENGINE PAD CODES THAT WE CHECKED HAD THE NUMBER ON THE LEFT SIDE OF THE FIIOIIEB NUMBER.
BUT THIS ENGINE DIDN'T.
COULD IT BE AN AFTER MARKET OR REPLACED ENGINE FROM THE FACTORY?
With those two numbers/codes, we can tell you where the engine came from - the ""EB" suffix was used on several different applications from '55-'67.
Thread Starter
8th Gear
Joined: Nov 2008
Posts: 8
Likes: 0
The block CASTING NUMBER is on the rear flange of the block, where the bellhousing bolts up, on the driver's side. The block CASTING DATE is on the same flange, on the passenger side, about 5" outboard of the distributor.
With those two numbers/codes, we can tell you where the engine came from - the ""EB" suffix was used on several different applications from '55-'67.
With those two numbers/codes, we can tell you where the engine came from - the ""EB" suffix was used on several different applications from '55-'67.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
8th Gear
Joined: Nov 2008
Posts: 8
Likes: 0
thanks John
I was able to get the rest of the numbers you told me about and here they are.
The rear driver side number was:3737379
and the passenger side number was: J307
I think the 3737379 number ran from 1957 thru 1959 not sure on the J307.
The engine code is FIIO1EB which is Nov. 01 I think, but this number had the 1004 underneath it on the pad.
I was able to get the rest of the numbers you told me about and here they are.
The rear driver side number was:3737379
and the passenger side number was: J307
I think the 3737379 number ran from 1957 thru 1959 not sure on the J307.
The engine code is FIIO1EB which is Nov. 01 I think, but this number had the 1004 underneath it on the pad.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Racer
Joined: Sep 2007
Posts: 429
Likes: 1
From: Jefferson Georgia
I think what you have is a late 57-58 block from a passenger car. the "E" suffix was used on corvettes in 57 but that was changed for 58 and the "B" isn't found in my NCRS Corvette Specifications Guide. The casting number used for 57 Corvettes is 3731548 and the casting number from your block would fit the 58 Corvette 3737739 This number was also seen in the "very" early 59 Corvette. I understand this probably don't help much with your friends situation but it's good info.
Racer
Joined: Sep 2007
Posts: 429
Likes: 1
From: Jefferson Georgia
I would also like to add. This engine wouldn't have been a replacement from GM or the dealer. This block was cast and built years before your friends car was built. The time gap is too great for something like this to be reasonable. I would rather think that this engine was replaced later in the cars life by a reputable person with the original VIN stamped on the pad. Check the VIN along with the additional numbers that are stamped on the front pad (1004)and see if they match. If this is the last 4 digi's of your VIN number your car is an early production 61 and would have originally had a block casting number 3756519. In late 61 (around mid June) the casting numbers changed to 3789935.
IMHO, I don't think your friend has the correct block for his car. However! this block being a 3737739 (used in Corvettes) does have value to it and could be used as a barter for the correct one if you can locate one that your friend needs. One last note to remember! The correct block for this car would also be a "Flint" block with the "F" not a "T".
Good Luck!
ZADSPAL
IMHO, I don't think your friend has the correct block for his car. However! this block being a 3737739 (used in Corvettes) does have value to it and could be used as a barter for the correct one if you can locate one that your friend needs. One last note to remember! The correct block for this car would also be a "Flint" block with the "F" not a "T".
Good Luck!
ZADSPAL
Thread Starter
8th Gear
Joined: Nov 2008
Posts: 8
Likes: 0
I would also like to add. This engine wouldn't have been a replacement from GM or the dealer. This block was cast and built years before your friends car was built. The time gap is too great for something like this to be reasonable. I would rather think that this engine was replaced later in the cars life by a reputable person with the original VIN stamped on the pad. Check the VIN along with the additional numbers that are stamped on the front pad (1004)and see if they match. If this is the last 4 digi's of your VIN number your car is an early production 61 and would have originally had a block casting number 3756519. In late 61 (around mid June) the casting numbers changed to 3789935.
IMHO, I don't think your friend has the correct block for his car. However! this block being a 3737739 (used in Corvettes) does have value to it and could be used as a barter for the correct one if you can locate one that your friend needs. One last note to remember! The correct block for this car would also be a "Flint" block with the "F" not a "T".
Good Luck!
ZADSPAL
IMHO, I don't think your friend has the correct block for his car. However! this block being a 3737739 (used in Corvettes) does have value to it and could be used as a barter for the correct one if you can locate one that your friend needs. One last note to remember! The correct block for this car would also be a "Flint" block with the "F" not a "T".
Good Luck!
ZADSPAL
Thanks a lot, I think this answers all our questions on the 61. I really appreciate all the work that everbody has put in to help me answer these questions. This is truly a great source of information.
I will definately recommend this forum to anyone that might need it.
thanks again
Jim and Ken
