I learn something new almost every day.
http://www.examiner.com/x-8598-Detroi ... tte-ZR1-a-lession-learned

I posted this on CF a couple of days ago. An interesting read if you're interested in the C3 ZR1.


This was written by forum member 66L36Coupe
Hey guys-

As SkunkWorks (Hey Charlie!) mentioned, I've done a bit of research on these cars after acquiring an unrestored '70 ZR1 Coupe last year.

Here's my take on the car. I stumbled across it online a few weeks ago while cruising the web at http://joeamatoscollectiblecars.com/...~056/Page.html . I emailed the dealer, Bo, who called me the next day. First, it was apparent Bo is not a "Corvette guy," but came across as a straight shooter and doesn't pretend to be an expert. Rather he's relying on the docs and records that came with the car - which appear to be fairly extensive. The car looks to have had some refurbishment over the past decade or so - but not sure how much was done and to what level. I asked Bo if this was the ZR1 that sold at the Palm Beach BJ auction, and he said it was. He told me he was asking for $189k for the car, but was listening to offers as biz has slowed-down in SoCal.

I asked for under-hood pics of the car, and he told me they (the dealership) were righting a few wrongs, like replacing the hoses and installing the correct 884 alternator that was missing when they acquired it as well as removing the ignition shielding, etc. He said didn't want to post pics until those issues were addressed - apparently he decided otherwise.

As for general ZR1 bits that appear on the car - they look to be present with correct corresponding dates/codes. Specifically, the rear-end code (456 HD posi) is a very strong indication of the car's authenticity; it's the exact same date & code stamp as my car (2FC 8 13 69W), and the exact same as at least two other known 456 posi optioned ZR1's - Charlie's old Bronze 456 optioned ZR1 pictured above is one of them. Charlie's ZR1 and my ZR1 were built only 69 units apart - that's basically the same day. The 456 posi units were most likely a left-over "batch" from the '69 model year run of L88's and 435hp cars, and were obviously built/shipped/stored together and then racked side-by-side on the assembly line specifically for use in the ZR1's. Nobody knows about the date similarities except a handful of ZR1 owners and experts (and now you studious CF's who have stayed awake thus far). Co-inky-dink? Don't think so. There is also some other date/code evidence regarding the M22's used, but I haven't confirmed those codes on this car. Note of caution: the stamp date on the engine pad falls on a Sunday (April 12, 1970). According to John Z - Sunday shifts were rare and employed only when they were severely backlogged. Was building a batch of ZR1/LT1's enough of a priority to have the engine assembly crew work a Sunday? You be the judge.

And by the way, Charlie's old ZR1 pictured above was restored by Rex Marshall in the '90's (restoration engine installed) and then changed hands a few times. It is now in the hands of a mid-west collector. I have been able to obtain a photo of Charlie's car's build sheet and use it as a guide to re-construct my interior order copy that was shredded by mice. The order copies appear to be virtually identical except for the color call-out, and that my car was built with NA9 California Evaporative Emissions Control. Even the hand-written numbers on the order copies are identical - obviously written by the same guy... fun stuff.

As for documentation on the car, Bo sent a photo (of a photo) of the tank order copy. It appears to be real and correct and confirms the ZR1 status. I'd post a picture of it, but it's his right to do so, and those interested in seeing the document should contact him directly.

Bottom line; I'd like to see the car in person to make a final judgment, but barring that, my gut says this is a real ZR1 - although I'm not clear on how much of the car is original. I'll be in LA next month, so if it hasn't sold by then, I'd like to go see it in person.

If it can be had for anything less than $150k, and proves to have no major issues, I'd call it a bargain.

Finally - there were a few questions about ZR1 factory installed equipment. I'm no expert, but have done a lot of research using my 98% original '70 ZR1 for comparison. Here's what the evidence points to about how the "ZR1 Special Purpose Engine Package" was bundled:

First, the "package" consisted the LT1 engine (see below for how it differed from standard LT1 powerplant), M22 HD close ratio transmission, F41 Special Purpose Suspension, J56 HD Brake Package, HD Aluminum radiator, and HD posi rear end. The only "options" available when ordering the special purpose engine package were deluxe interior and tilt/tele column. PW, PS, AC (like all LT1's), radios, rear window defrosters and PO2 wheel covers were precluded from availability. The C3 ZR1's can in essence be described as an L88-prepped chassis with an slightly modified LT1 stuffed in it.

The LT1/ZR1 Engine WAS a different assembly than the standard LT1 - Hence the different suffix codes assigned to call-out the non-standard parts required. Although the internals, intake and exhaust were identical to standard version LT1, the CTV suffix code in '70 (and the CGY in '71 and CKZ in '72) were fitted with a 10.5" light weight L88-style flywheel and corresponding 403 bell housing as well as a High-torque L88 ('69 coded & dated) starter with aluminum nose. Some say the ZR1's used a cast-iron balancer pulley, but I've only been able to report stamped units.

As for the questions regarding fan shrouds, the '70 & '71 ZR1's all appear to be fitted with the base-engine type metal fan shroud. The '72 cars were not. There is one other item often overlooked when reviewing the HD radiator/cooling system on ZR1's; it's that the HD radiator used a modified (widened) radiator core support. They appear to be left-over pieces that were modified originally for the '68 and '69 run of L88's. My ZR1, as well as Sal Carbone's '70 ZR1, have a grease pencil marking written on the core support stating, "L88 ONLY" (my car) or "L88" (Sal's car) so the line workers could tell them apart from the base-engine supports when installing the 3007436 Aluminum HD radiator. I suspect other "real" ZR1's will have this marking as well.

There are many other details that can help verify the status of C3 ZR1's that aren't public knowledge, and in some ways, they're better kept under wraps as not to encourage a spate of counterfeiting like we've experienced with other high-performance optioned Corvettes. After all, you can buy most of the parts required to "build" your very own ZR1. The devil is always in the details - and the documentation.

I bet the author of the story in that link has no idea what his UID means.

Good, interesting info, but typical of some internet reporter to just post his non-researched drivel on the web and expect everyone to be in awe.

Matthew

Found this for your enjoyment.

Jim

Facinating insights on the gen 1 Z...