Casting # year verification
Thread Starter
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
Casting # year verification
Hi
I would like some info on my casting # on a 66 427/425. The # is 3804351 and on the lower right there is a P156 and lower left Kpass17 and there is also hyperf in the casting. I have had the car since 78 and this is the 2nd time I have had the block decked so the original # is only faintly visible (motor is already painted and in the car)
When I first bought the car I had everything checked out by a vette shop and was told everything was ok. Now I am being told that this # designates the block as only being available in 67 models. I have always thought I had the original motor but this guy says no and has a book to back it up. I would appreciate any clarification.
Thanks
I would like some info on my casting # on a 66 427/425. The # is 3804351 and on the lower right there is a P156 and lower left Kpass17 and there is also hyperf in the casting. I have had the car since 78 and this is the 2nd time I have had the block decked so the original # is only faintly visible (motor is already painted and in the car)
When I first bought the car I had everything checked out by a vette shop and was told everything was ok. Now I am being told that this # designates the block as only being available in 67 models. I have always thought I had the original motor but this guy says no and has a book to back it up. I would appreciate any clarification.
Thanks
Drifting
Joined: Jul 2005
Posts: 1,977
Likes: 194
From: Putnam Valley, New York. Amateur Radio Operator K2NS
Block Id
3904351 is a 1967 only casting number. Check your date code again, there is no month coded as "P". The P156 denoted the 15th day of some month of 1966, but as I mentioned above, there is no month for the letter "P".
RON
Thread Starter
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
Thanks for the reply
When I got the info on the phone today I was told 3804351 and not 3904351. If this does not seem correct I will ask the person doing the resto job to check again. I suppose the P could be either a D,B or F. However I will ask him to check again and post it as soon as I get the info.
Doug
When I got the info on the phone today I was told 3804351 and not 3904351. If this does not seem correct I will ask the person doing the resto job to check again. I suppose the P could be either a D,B or F. However I will ask him to check again and post it as soon as I get the info.
Doug
Safety Car
Joined: Aug 2000
Posts: 4,148
Likes: 642
From: Bandera Texas
Originally Posted by Shurshot
Hi
I would like some info on my casting # on a 66 427/425. The # is 3804351 and on the lower right there is a P156 and lower left Kpass17 and there is also hyperf in the casting. I have had the car since 78 and this is the 2nd time I have had the block decked so the original # is only faintly visible (motor is already painted and in the car)
When I first bought the car I had everything checked out by a vette shop and was told everything was ok. Now I am being told that this # designates the block as only being available in 67 models. I have always thought I had the original motor but this guy says no and has a book to back it up. I would appreciate any clarification.
Thanks
I would like some info on my casting # on a 66 427/425. The # is 3804351 and on the lower right there is a P156 and lower left Kpass17 and there is also hyperf in the casting. I have had the car since 78 and this is the 2nd time I have had the block decked so the original # is only faintly visible (motor is already painted and in the car)
When I first bought the car I had everything checked out by a vette shop and was told everything was ok. Now I am being told that this # designates the block as only being available in 67 models. I have always thought I had the original motor but this guy says no and has a book to back it up. I would appreciate any clarification.
Thanks
A correct 66 block for your car should be 3869942. The 951 block will be very tradeable if you want to get it all correct.
Race Director
Joined: Oct 2005
Posts: 12,468
Likes: 1,548
From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
Originally Posted by jimgessner
3904351 was only used in 1967 passanger and Corvette applications. 2 bolt main and 4 bolt for the 435hp and L-88 versions. K17 refers to November 17 date. The motor is either a PASS or HIPERF......but not both. Corvettes were HIPERF only.
Doug
Thread Starter
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
All that I can say for sure is that it is a 4 bolt main and I am trusting the restro man to be reading the #'s correctly. The car is located about 500 miles from where I am at in SC. Had I sought this info before doing a ground up 5 year project I would have sought to trade off for the correct #. The man who did the motor has done others for me in the past with excellent results. It is set up to run on pump gas and should produce 475 hp plus. (Has a 750 demon carb. and a mallory unilite dist. but other than that the motor looks original)
I am waiting for the front bumpers and tires and then it is good to go other than installing the steering column.
Thanks for all the info.
Doug
I am waiting for the front bumpers and tires and then it is good to go other than installing the steering column.
Thanks for all the info.
Doug
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Thread Starter
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
I have rechecked the casting # with the shop doing the work and they maintain that the second digit is an 8 and not a 9 for whatever that means. I remember back in 66 when the 427 was available in the chevelle and impala and it was rated at 385hp. This was a two bolt main motor and the way I understood it was that it was primarily for the west coast because the 396/375 motor was not available in Calif. I question that accuracy of that statement. I did not know that they were already requiring cars to pass certain smog requirements in Calif. way back then. I was a young car fan at the time and remember seeing an advertisement from GM for 427 chevelles in a car mag. Whatever the outcome, the year of the block does not change the bottom line.....that being the car has been off the road for 15 years and I am looking forward to driving it again. I deeply appreciate all the replies and I think this forum rocks, big-time. 
Thread Starter
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
Safety Car
Joined: Aug 2000
Posts: 4,148
Likes: 642
From: Bandera Texas
K-19 appeared for the first time
Originally Posted by chewy
The 375 HP and 425 HP were smog exempt for 1966 in Cal. The 942 is the only correct block for both the full size cars and the Corvettes with the 425 HP.
However, the K-19 AIR INJECTION REACTOR smog pump system appeared on Corvette (and passager) small block 300 and 350hp engines sold new in California. 2380 Corvette cars had the item.
In 67, the K-19 system appeared on all California new Corvettes including 390, 400 and 435hp big block engines. Only 2573 Corvettes had them in spite of the added big blocks. Not a big increase.
In 68, the item was on all cars in the 48 states, as Federal Smog laws took over.
