Quote:
Originally Posted by Martinjlm
Readers Digest version
- There were only a few built for 1989. Im not certain if those were closely held or if they got into public hands. All I know is I had to account for them when doing the end of production. Specifically, I had to account for VINs and there were some 89 VINs
- Most of the cars sold were 90 and 91.
- There were three mechanically different engine arrangements. This is the root of why I say its the best car that should have never been built.
- 89-91 were 2-bolt main
- 92-95 were 4-bolt main. Whys that a big deal? Because blocks and cranks are suddenly not interchangeable. There was less than 2,000 4-bolt vehicles built. But at the end of production, only 4-bolt main product was available to support service. So most service issues would have to be managed at a long-block level of content.
- 92-93 increased to 405(?) hp.
- 94-95 had similar hardware as 92-93. I believe the heads were different but I cant recall how different or whether they were interchangeable.
- 94-95 had different PCM and wiring harness. I cant recall if there were mechanical differences between the 92-93 and 94-95, but I do recall that the engines are not interchangeable, at least because of the PCM and wiring harness. If I recall correctly, there were (3) different designs of cylinder heads.
- At the end of the run I was at the Mercury Marine plant in Stillwater to watch the last several engines come off the line. I bought the last 20 or so complete engines off the line for service operations. They were boxed up and shipped out to an engine remanufacturer I used for other engine programs. They were only available to authorized ZR1 dealers upon confirmation of a VIN. Thats why I know there were 89s. We had 89 VINs in the database.
- But the fun fact was, since most of the vehicles sold were 89-91, the engines I had set aside would not be able to use those engines UNLESS they also purchased a PCM and wiring harness. Dealers also had to forward a $20,000 core charge for each engine replaced. This was to make certain that the removed engine a)actually came out of a ZR1 and b) to start to set up a remanufacturing process for the engine.
Parts level service also had to be managed by VIN, since some of the engine content changes were running changes made in the middle of a model year, without any assurance of retrofit.
Many of the key suppliers of parts for the 89-91 vintage were out of business. In some cases, their going out of business drove product changes. In other instances, product changes drove original suppliers out of business. In our planning, where we could replace a 91 part with a 95 part we did, even if it meant replacing other mating parts.
For some of the major parts we had to find new suppliers altogether because of original suppliers going bankrupt. This meant paying what amounted to prototype prices for a small store of service parts. We even had to find a new cylinder head casting supplier because the foundry(ies) that produced the original units went bankrupt. 4-digit pricing, first digit NOT a 1. And that was before machining and valve train assembly. Remember, this is a DOHC.
So
first design, where most of the volume is, are 2-bolt main with cylinder head design A. Less than 2,000 vehicles are 4-bolt design, so different blocks and cranks. And those <2,000 have cylinder head designs B or C, depending on when they were built. And most of the service parts available were of vintage C. What could go wrong?
So much for Readers Digest. |
That's wild! I appreciate the long form, there's some great history there for all of us to file away. Thanks for sharing.
I've watched a few segments on the C4 ZR1 over the last year and I once thought maybe, if I can find a decent driver-quality example, it's something I might like to have. I hadn't gotten to my Camaro-levels of enthusiast knowledge with C4 Corvettes yet, and had no idea about the potential adventure maintaining or sourcing parts for one of those engines can be. I still think they're awesome cars and they certainly captured my attention back then, as a kid, and it's a car I still admire now.
The ~$59k MSRP of a ZR1 back in 1990 is a good reminder that the C8 is a stunningly good value today given the advancements and increases in performance.