Help with 1968 Convertible engine Id
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
I checked the sway bar size today and they are as you have described, the front is 15/16" and the rear is 9/16". One more clue it was a big block car. Thanks for the info.
Team Owner
Joined: Jul 2008
Posts: 23,419
Likes: 22
From: In limbo
St. Jude Donor '13-'15, '17 thru '22
At this point, I would be feeling pretty comfortable that this car was likely a big block car out of the factory. Of course, a lot can happen over 41 years, but if someone "converted" this small block car to a big block car, it sure looks like they did a good job. In the end, without the original motor, I don't think it matters much or any if the car was originally a big block or not. As long as all the performance stuff is there so that it drives and handles like it is supposed to, I don't think I would view it any differently if that stuff was added, assuming it was added correctly.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
At this point, I would be feeling pretty comfortable that this car was likely a big block car out of the factory. Of course, a lot can happen over 41 years, but if someone "converted" this small block car to a big block car, it sure looks like they did a good job. In the end, without the original motor, I don't think it matters much or any if the car was originally a big block or not. As long as all the performance stuff is there so that it drives and handles like it is supposed to, I don't think I would view it any differently if that stuff was added, assuming it was added correctly.
For me, the issue is what to do next. Frankly, I bought the car to flip and try and make a few bucks to pay some bills and possibly put towards a 70. But, the longer I walk around it and crawl under it, the more interested I am in putting an engine in it and putting it back on the road. It has a great frame and windshield frame and a lot going for it, but needs a lot of work also, mostly body and interior work.
Thanks to everyone for all the help in trying to sort out what I have. If you know of anyone that might be interested in this car, just drop me an email or PM. If I decide not to keep it, it will go on Ebay as soon as MVA finishes processing the title.
4th Gear
Joined: Feb 2009
Posts: 4
Likes: 0
I also need help
HI
I AM NEW TO THE FORUM AND JUST BOUGHT A 68 L89 THAT WAS BUILT DEC 2, 1967. CURRENTLY HAS A CE BLOCK DATED LATE 69 AND HAS NO DOCUMENTATION TO PROVE IT BEING AN L89. WHAT WOULD THE CORRECT NUMBERS BE ON THE ORIGINAL ENGINE IF IT WERE AN L89. I believe the casting should be a 321 but what about the number? (3963512....IU)?
thanks danny
I AM NEW TO THE FORUM AND JUST BOUGHT A 68 L89 THAT WAS BUILT DEC 2, 1967. CURRENTLY HAS A CE BLOCK DATED LATE 69 AND HAS NO DOCUMENTATION TO PROVE IT BEING AN L89. WHAT WOULD THE CORRECT NUMBERS BE ON THE ORIGINAL ENGINE IF IT WERE AN L89. I believe the casting should be a 321 but what about the number? (3963512....IU)?
thanks danny
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
HI
I AM NEW TO THE FORUM AND JUST BOUGHT A 68 L89 THAT WAS BUILT DEC 2, 1967. CURRENTLY HAS A CE BLOCK DATED LATE 69 AND HAS NO DOCUMENTATION TO PROVE IT BEING AN L89. WHAT WOULD THE CORRECT NUMBERS BE ON THE ORIGINAL ENGINE IF IT WERE AN L89. I believe the casting should be a 321 but what about the number? (3963512....IU)?
thanks danny
I AM NEW TO THE FORUM AND JUST BOUGHT A 68 L89 THAT WAS BUILT DEC 2, 1967. CURRENTLY HAS A CE BLOCK DATED LATE 69 AND HAS NO DOCUMENTATION TO PROVE IT BEING AN L89. WHAT WOULD THE CORRECT NUMBERS BE ON THE ORIGINAL ENGINE IF IT WERE AN L89. I believe the casting should be a 321 but what about the number? (3963512....IU)?
thanks danny
I am not an expert at this, so I am sure others will chime in. Going by what I see in the Corvette Black Book, the 68 L89 would have had a suffix code of IU and the block number would have been 3919842. This is what I see in the book, so it may not be totally correct. There are many others here on the Forum with much more knowledge and experience than I. As I recall, the 3963512 did not come along until 1970.
Intermediate
Joined: Oct 2008
Posts: 30
Likes: 0
Danny,
I am not an expert at this, so I am sure others will chime in. Going by what I see in the Corvette Black Book, the 68 L89 would have had a suffix code of IU and the block number would have been 3919842. This is what I see in the book, so it may not be totally correct. There are many others here on the Forum with much more knowledge and experience than I. As I recall, the 3963512 did not come along until 1970.
I am not an expert at this, so I am sure others will chime in. Going by what I see in the Corvette Black Book, the 68 L89 would have had a suffix code of IU and the block number would have been 3919842. This is what I see in the book, so it may not be totally correct. There are many others here on the Forum with much more knowledge and experience than I. As I recall, the 3963512 did not come along until 1970.
3963512 427 69 Chevelle,Camaro COPO (Central Office Production Order)
3963512 427 69 Corvette Late 69
3963512 454 70 Corvette,Passenger 360,390 HP
3963512 454 70 Chevelle LS-6 450 HP
3963512 454 70-71 Pass,Chevelle, Monte Carlo
3963512 454 71 Corvette 365,425 HP
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
3963512 Block appears to have started in 1969.
3963512 427 69 Chevelle,Camaro COPO (Central Office Production Order)
3963512 427 69 Corvette Late 69
3963512 454 70 Corvette,Passenger 360,390 HP
3963512 454 70 Chevelle LS-6 450 HP
3963512 454 70-71 Pass,Chevelle, Monte Carlo
3963512 454 71 Corvette 365,425 HP
3963512 427 69 Chevelle,Camaro COPO (Central Office Production Order)
3963512 427 69 Corvette Late 69
3963512 454 70 Corvette,Passenger 360,390 HP
3963512 454 70 Chevelle LS-6 450 HP
3963512 454 70-71 Pass,Chevelle, Monte Carlo
3963512 454 71 Corvette 365,425 HP
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