I am/was building a BBC 461 for my car. I got the block from my dad which he had laying around since his engine building days. Last week, I started running the numbers on the block and I come to find out that my block might actually be quite rare. The numbers on the bellhousing flange read 3869942 with a build date of like June of '66. In one of my books, it says that these blocks were built from '66-'67 with either 2 bolt mains or 4 bolt mains. Since my block is a 4 bolt, my dad was telling me that this block would be the same block used in '66 427/425 HP Vette. Then a couple of minutes ago, I just decided to see how rare might my block be. I went to eBay, typed 3869942 and did a search. Found one on eBay from the seller Cranecorvettes ( I do not know this person, nor am I intentionally trying to advertise his block) asking $4,800 buy it now.

Now I do have one problem with this engine. I had this whole engine built, but was uncomfortable with how hard it was to turn the engine over. Turns out that my #5 rod is slightly tweaked. So, I was thinking since it was already so late in the year. I might be better off disassembling everything and make sure all my other rods are straight.

My thoughts are that maybe I should look for another block to build rather than using my current block. There is absolutely nothing wrong with the block. The block was blasted, hot tanked, and magnafluxed. Then I had the block align honed and bored the cylinders .030. However, for me the block is no real significant value because I do not own a 66-67 vette. I would just hate to be on a quite road one day spin her up to 7,000 and have a rod snap on me and there goes a perfectly good NCRS block. I am thinking about selling this block (no where near what cranecorvettes wants for his) and buying myself another GM 4 bolt block, or quite possibly save up some extra cash and with the sale of the other block buy a Dart or World block. My block has never had a vin# stamped on it, and could still be decked if the next owner wishes to do so. What are all your thoughts?

 

My opinion....JACKPOT BABY

Sell it and fund your build

 

Hi F90,
I'd think the block would have the greatest value to the owner of the car (if it still exists) it came from. Is there still a VIN stamp, build date and suffix on the pad? If the block was decked at some point the stamp could be gone.
Regards,
Alan

 

I'm going to take a guess that there is no VIN # stamped on the block

 

If the block never had a VIN stamped on it it was never installed in a car by the factory, so you'll never find the original owner. However, it is probably worth a lot more to the owner of a 66 or 67 Vette. How much do you think your current block is worth? How much would a "generic" BBC cost? Take the money and run.

 

Hey Alan,
Actually the engine was a 427/425HP engine, but it never made it into a Corvette. It was actually bought over the counter and put into a boat. Years down the road, the owner of the boat wanted more HP. So my dad ordered him a second design L88 (he was a mechanic at a chevy dealership at the time) and my dad gave him $100 for the 427/425HP engine. This happened in the late 60's - early 70's and the block sat in a garage ever since. If it had not been for the pitting in the cylinder walls the block would've been perfect to use as a standard bore. With that being said, the engine has never had a Vin # stamped on the block. It has some numbers stamped on the pad (I assume that is the suffix on the pad?), but not where the vin# should be.

I do agree with you in saying that it is probably worth a lot more to a 66-67 vette. If I were to sell it and the buyer had a late '66 or early '67 vette, he could have his vin # stamped on a fresh pad that has never had a vin # on it. I am not saying I agree with stamping a block that did not originally come with the car, but as we all know, it happens all the time. I'm not sure exactly how much the block is worth. I assume it may range from $4-5k, being that the guy who is selling it deals with a lot of old corvette stuff. I know I wouldn't ask for the money he is asking, and I have a more complete set-up than he does. A "generic" BBC could probably be had for $500 maybe a little more + the machine work. My guess that to find another block and have the machine work done, I'm probably looking at $1k.

What do you all think would be fair as for as asking price?
My block is ready to assemble with .030 pistons. I also have some of the original oil filter canister parts to the block. The differences between my block and the other is that his block has been resleeved to take a standard piston, but needs a final hone. He also does not have main cap bolts. My block has main cap studs that allows one to use a windage tray. His block has also been true decked. Mine on the other hand is still the original deck height. The only thing that I can think would hurt my engine is that the block has been clearanced for a 4 in. stroke with 7/16's rods.

 

What's the casting date?

The 3869942 was used by Chevy only in '66 and in Corvettes, Impalas, and maybe other applications, for 427 ci.

It is valuable to a Corvette restorer with a 427 car dated after its cast date.

The date cast is important, because it tells what date of car it is appropriate for for a "restoration", as defined by NCRS. Any 427 car built a few days subsequent to the cast date up to 6 months conceivably could have used this block, and can use it under NCRS guidelines.

Now I'm going to open a can of worms here, again, regarding the propriety of a restamp and restoration, but again, a restorer who wants a date-correct 1966 would pay dearly for this block.

Cranes is a good guideline. Also, look at completed auctions on Ebay for this and similar mid-year 427 blocks. It will not be unusual to see $2,000-$4,000 range.

 

The engine has F 3 6 cast in the block. I believe that means June 3rd, 1966. You say this could only be a '66 engine. Why could it not be used in a '67 run? My book tells me that it is a '66-'67 block. According to Crane this 942 block was also used for the L88's, L89's, and the 435 HP tri-powers. The date is so late in the '66 year that I could see this engine fitting in a very late '66 and early '67 production car. Is there something I am not aware of?

 

You are correct, but only to a point. It (942) was used in early production only in '67, that usually means that there have been a couple noted, but with a June 3 cast date, and production of '67s beginning in Sept, 66, in all likelyhood, this would be most "appropriate" for a '66 427. Despite what NCRS says about the 6 months, it is a stretch to think that a 942 would be sitting around Tonowanda or St. Louis for all of June, July and August. But again, it passes NCRS muster up to mid October, so you can advertise it as such.

 

Thanks Ravine! You are indeed a wealth of info! I appreciate your time and your knowledge.

As for the block, I think I am going to sell it and grab another 4 bolt block. With the left over money, I think I will use it to help fund a paint job for my dad's vette.

 

wise choice a 942 block is a sought after block right after the 351

 

I think that's wise. Clearly, if you don't need this particular block for your build, you can get a used one for a song anywhere.

This block will fetch more than what you pay for another block for sure.

I can't tell you how much, but this will be valuable to a restrorer of a late '66 or early '67.

Good Luck!