C3 - CE block questions/value, 1971 LT-1 Vert

[Chuck Caldwell]

Need some help and advice...

Found/purchased a 1971 LT-1 Vert with everything numbers/date coded correct on the entire car except the block. Original Vert car, standard interior, no hit body, one repaint (original color), body off.

I have a couple of Q's......

- Is a 1974 3970010 block exacly the same as a 1971 3970010? IE: same bore, 4-bolt mains, etc...is there any difference? Engine has been rebuilt using all of the original parts (manifold, carb, heads, pink rods, correct steel crank, correct LT-1 cam)

- Secondly, how bad does having a CE replacement block in this car hurt it's overall value? Everything else is correct, carb (build date matches), M-21 trans (vin matches), rear end, heads, intake, smog, TI distributor, etc....also the owner have the tank sticker for the car.

Any advice and recommendations would be greatly appreciated

thanks in advance....
Chuck Caldwell
Wisconsin

[Jack H.]

Re: C3 - CE block questions/value, 1971 LT-1 Vert

I'm not sure what a 'Vert' car...possibly an abbreviation for convertible?

In Flight Judging there are 4500 possible points with 350 allocated to the cylinder case. Since you have an '010 block which was correct for your '71, but it's casting date falls well after the allowable 0-6 month interval prior to your car's build date, our published rules require a 175 point deduction. There's no secret here, the club's judging process is reduced to writing...

Therefore, you lose 175/4500 or 3.8% for the replacement block in the car. It's still possible to obtain a Top Flight award (ESPECIALLY if you drive the car to a meet and make use of the club's milage driven credits), but literally EVERYTHING else about the car must be correct/original and in excellent condition for the car to achieve the 94% minimum score needed if it's judged on a standalone basis.

[Joe L.]

Re: C3 - CE block questions/value, 1971 LT-1 Vert

Chuck-----

Notwithstanding the judging issues as far as dates are concerned, the 3970010 block used for 1971 and 1974 are "virtually" the same. The blocks, themselves, are definitely the same in every way. However, keep in mind that the main bearing cap configuration is NOT part of the block, itself. The main caps are part of the finished machining and assembly of the block and are, in no way, part of the piece known as 3970010.

As a matter of fact, the 3970010 blocks were built up into BOTH 2 and 4 bolt main configurations. For 1971, all 3970010 blocks built up into LT-1 finished engines would have had the 4 bolt main configuration. However, most 1971 base engines were built with 2 bolt mains (some may have been 4 bolt, though, as 1971 was a "transition year" as far as this was concerned). For 1974, base engines were usually 2 bolt while L-82 were usually 4 bolt.

With a 3970010 block there's really no way to tell, for sure, which main bearing cap configuration it has without actually pulling the pan and checking it visually.

Also, virtually all, if not all, 2 bolt usage of the 3970010 block were equipped with nodular cast iron crankshafts. 4 bolt main blocks used EITHER the nodular cast iron OR the forged steel cranks. All L-46, L-82, and LT-1 engines built from the 3970010 block used the forged steel cranks; all others used for cars used nodular cast iron.

[Chuck Caldwell]

Re: C3 - CE block questions/value, 1971 LT-1 Vert

Joe,

thanks for your response and sharing your detailed knowledge in regard to my question ....this is exactly what I wanted to know.

much appreciated!

Chuck

[Chuck Caldwell]

Re: C3 - CE block questions/value, 1971 LT-1 Vert

Thanks for all the input.....however, it looks like I may not be able to get this car though.

I'm really pissed off .....it seems someone from either this forum or the Corvette Forum (where I posted the same Q's), also knew about this car and paid the owner a visit today, about an hr ago, to tell him he was selling the car to me for too low of a price....now the owner says he's going to keep/finish the car himself and that the person who visited him today had seen my post, but he would not tell me who.

If I find out who it is, I'm calling them out!!!

This is no way to do business in my book, and whoever did it needs to be publically flogged.

[Warren F.]

Re: C3 - CE block questions/value, 1971 LT-1 Vert

Chuck:

To answer the part of your question concerning value, the LT-1 engine of course would be the most important reason to acquire the convertible 'vette. Since all the unique and important components seem to be intact, I would say that probably 1/5th of value is diminished. Most of the time a complete missing engine would usually devalue a car like this more closer to 1/2.