jwappes

Looking at a 1970 corvette. Owner thinks the orginal engine was a big block. How can I tell from the VIN or any other way what the ^vette was born with?

Alan 71

Hi jw,
The 1970 VIN won't give you any engine information. That started in 1972.
The tank sticker glued to the top of the gas tank has the information, but isn't readily available.
There are some hints in the engine compartment like the type of radiator, the tachometer red line in the interior, the type of fasteners used on the half shafts, and the presence of a rear sway bar.
I don't really think it matters much at this point if it was a bb originally or not…. it wouldn't bring a dollar premium with the original engine missing, and you can make it a bb if you want to.
Regards,
Alan

jwappes

There are a lot of things that makes me lean towards a LT-1, but it has a cylindrical brass expansion tank for the radiator.

BBCorv70

I think the brass cylindrical expansion tank was for big blocks with AC.
Maybe someone else could verify.

Without the original engine, I see the only advantage of having been originally built with a big block being the big block parts may still be there, making restoration a bit cheaper. Fewer parts to chase down. The value would be determined by the market interested in a driver, not an original.

One could go the unethical route as well, buy a restamped block and sell it as an original. There are vendors offering this service calling them restoration engines. Trouble if the seller gets caught representing it as 'original'.

LS4 PILOT

It's what ever you want it to be at this point. Resto mod, Vortec or LS it, Without tank sticker or other stuff to verify ....it can be anything your heart desires. When it lost it's engine ...it lost the part that seperated it from a base car. I'm advocate of 72 up as collectables . The vin ., at least proves it was equipped at birth with a certain motor.

Without the original drivetrain , it's just any other corvette IMO.

I would not pay BB price without the original drivetrain.

joewill

A 70 that was a big block originally will have stiffer front springs, larger sway bar in front, sway bar in back, heavier fasteners on the half shafts, bigger radiator, big block hood to fit taller engines..... and other characteristics to make it more desireable than a base engine car..

I have argued this in the past also that I would pay incrementally more for these characteristics than I would a base engine car if both were NOM.. not a lot more.. but more.. maybe 10% giving all other equal parameters.

Easy Mike

Evaluate the car for what it is, not what it might have been. Do not assume it was a big block; do not assume it was an LT-1.

Good luck.

BBCorv70

Much depends on what the buyer wishes to do with the car. It has no value to the crowd who buys only 'originals'. Its market is the crowd who buy drivers.

jwappes

what are the red line marks on the different engine

jwappes

Probability the best advise. Thanks.

Alan 71

Hi jw,
For 1970 I believe the redlines are:
350/300 5300
350/350 6000
350/370 6500
454/390 5600
Regards,
Alan

jwappes

More about correct engine. Just looked at ^ vette again, found engine code, but can not find correct engine for the code. The number is V0428TAX. Can not find the TAX. Did I get all the number John.

Alan 71

Hi j,
The site nastyz28 has good engine decoding information.
'TAX' looks like it was used in both 70 and 72 in conversion vans and C-10 trucks.
Regards,
Alan