You will be taking a giant leap of faith to assume that they are exactly the same. The best thing to do is compare the BOSCH numbers and see if they are the same as your ABS unit. The Bosch website had information regarding this system online, they might have access to the testing procedure or equipment. There are good used ABS units out there but the ABS really likes to fail due to faulty wheel sensors and wiring issues.

The ABS system used in the early Corvettes is very basic and not at all what we have today. The 1988 Corvette has 2 lines from the master cylinder to the ABS box. One supply and one return. There are several lines going in and out of the ABS unit. The ABS system can only effect either front wheel using solenoids to control the pressure. The rear of the car is one line out of the ABS box going to the left wheel and then the right wheel. This is a very crude attempt at making ABS work in the C4. Today we have ABS pumps to make pressure and much better components so we have a truly functional 4 wheel ABS system. I would never trust nor expect the original C4 system to work like modern ABS does.

I have a 1988 Coupe and I had an ABS issue and it turned out that the Lateral Acceleration sensor had broken loose from its mount and was swinging back and forth. This little boo boo made the system go crazy. It re-attached more securely and now it was better. The wheel sensors are very problematic, they are I believe "Hall Effect Sensors" and simply count how fast the individual wheel is going. These sensors are exposed to a terrible environment and I am not surprised to see them failing like they are. I have been checking the connectors to be sure they are plugged in and then spinning the wheel to see if they are working.
If and when a wheel sensor fails on my car I am going to look into replacing it with an "Off the Shelf" sensor used for other cars or purposes. I had to source a hall effect sensor to control a 3 cylinder diesel generator's speed.

On the 1988 Corvette it has a ONE year only Master Cylinder, they are getting harder to find as time passes. I really want everything to work if possible on the car, especially the safety equipment.

I wish you the best in solving your ABS woes. Be sure to check your wheel speed sensors for operation before you start replacing the more expensive parts. Start at the easy stuff and work your way up, it is generally cheaper that way!

 

86-89 should be all the same Bosch II units, II-S are 90-94 and V is 95-96.

I had to buy a Kent Moore tester unit to check mine out when I had a relay fault.