I found it by searching the bay for ZR* but based on the posts here the car is not too much of a big deal
C3 ZR engine code ??? CKZ ???
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 9,127
Likes: 16
From: off leash
St. Jude Donor '21
C3 ZR engine code ??? CKZ ???
This Corvette coupe is optioned as an standard LT-1, but the factory installed the CKZ engine destined for the legendary ZR-1! Corvette experts around the country are fascinated by this engine/option combination. The car is numbers matching and has all the correct LT-1 options, but the factory installed an engine with ZR-1 performance option code. Rare indeed!
I have no intent towards the car, just trying to educate myself.
I'm sure some others have come across this as it is on the bay but I don't want to break the rules with a link so I just copied and pasted the applicable parts below.
1972 Corvette LT-1 Coupe, Numbers Matching, with ZR-1 engine pad stamping!
This Corvette coupe is optioned as an standard LT-1, but the factory installed the CKZ engine destined for the legendary ZR-1! Corvette experts around the country are fascinated by this engine/option combination. The car is numbers matching and has all the correct LT-1 options, but the factory installed an engine with ZR-1 performance option code. Rare indeed!
The Bryar Blue paint is in good condition for its age. The odometer is working and shows 85,448 original miles. The exterior trim is all original right down to the rims and center caps. The black interior has been restored and is in excellent condition. The frame, radiator support and suspension pieces are solid and rust free. The vacume system for the headlights and wiper arm door is all new and a new gas tank has been installed.
A complete mechanical restoration was performed by ex-Richard Petty and Richard Childress car builder Rick Mann. The engine was balanced and blueprinted and filled with a Callies crank, Eagle Rods and 10:1 Speed Pro pistons. The top end consist of a Comp Cams hydraulic flat tappet cam with Brodix aluminum heads and Aluminum Roller Rockers. The original factory high performance aluminum intake is topped with a Holley 750 CFM carburetor. An MSD tach drive distributor and ignition box have been installed as upgrades for the ignition system.
The numbers matching M-21 close ratio transmission and posi-traction rear end have been rebuilt and all suspension bushings have been replaced. A complete book of restoration details and reciepts are available.
This Corvette coupe is optioned as an standard LT-1, but the factory installed the CKZ engine destined for the legendary ZR-1! Corvette experts around the country are fascinated by this engine/option combination. The car is numbers matching and has all the correct LT-1 options, but the factory installed an engine with ZR-1 performance option code. Rare indeed!
The Bryar Blue paint is in good condition for its age. The odometer is working and shows 85,448 original miles. The exterior trim is all original right down to the rims and center caps. The black interior has been restored and is in excellent condition. The frame, radiator support and suspension pieces are solid and rust free. The vacume system for the headlights and wiper arm door is all new and a new gas tank has been installed.
A complete mechanical restoration was performed by ex-Richard Petty and Richard Childress car builder Rick Mann. The engine was balanced and blueprinted and filled with a Callies crank, Eagle Rods and 10:1 Speed Pro pistons. The top end consist of a Comp Cams hydraulic flat tappet cam with Brodix aluminum heads and Aluminum Roller Rockers. The original factory high performance aluminum intake is topped with a Holley 750 CFM carburetor. An MSD tach drive distributor and ignition box have been installed as upgrades for the ignition system.
The numbers matching M-21 close ratio transmission and posi-traction rear end have been rebuilt and all suspension bushings have been replaced. A complete book of restoration details and reciepts are available.
Drifting
Joined: Oct 2007
Posts: 1,254
Likes: 5
From: Brown Summit North Carolina
My understanding of the ZR-1 cars is that they were a LT-1 with several heavy duty extras added. All of the added stuff made the car more durable and maybe handle better on a road course. But as for power , it is just an LT-1.
I have seen the add on e-bay you are talking about.
To me this seller really has nothing to bost about. If this is a true factory block stamped for a ZR-1 that made it into a LT-1 then I see no WOW here. He has a screwed up stamp. But the stamping looks odd also.
Actually this would make me pass on the car.
just my .02 worth.
David
I have seen the add on e-bay you are talking about.
To me this seller really has nothing to bost about. If this is a true factory block stamped for a ZR-1 that made it into a LT-1 then I see no WOW here. He has a screwed up stamp. But the stamping looks odd also.
Actually this would make me pass on the car.
just my .02 worth.
David
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
The documentation I have shows the ZR1s came with the LT1 motor, Cars were radio delete, no AC, No Power windows, had the F41 suspension, rear end gears up to 4.56,(YE3)Cars shipped bare wheels with no trim rings or center caps, J50/J56 HD Brakes. Cam was solid lifter, 0.452 intake, 0.455 Exh, 800cfm Holly pn R-4489-A(70 ZR1) 6,500rpm Redline tach
70-71 had no fan shroud and 72 had metal shroud
72 ZR1 option was $1010.
70-71 had no fan shroud and 72 had metal shroud
72 ZR1 option was $1010.
Pro
Joined: Aug 2001
Posts: 507
Likes: 5
From: Seattle WA
The C3 ZR1's used the "base" LT1 engine. That is to say, it was virtually the same as the standard LT1 in regard to HP, torque, etc. But here's where it differed:
All '70-'72 ZR1 coded LT1 engines required:
Is finding one of these suffixed engines significant? Yes - if it's in a ZR1 with all the other HD bits. Otherwise, I would consider it only "interesting" - but only if it can be proven it was installed on the line. It would be fun to inspect the car to see if there were any other ZR1 indicators - as well as investigating if any "real" ZR1's bracketed the car on the production line, as they often did.
All '70-'72 ZR1 coded LT1 engines required:
- -HD hi-torque starter from the L88 parts bin (Delco 351)
- -L88-style lightweight flywheel (smaller dia.,156 tooth, PN 3856579)
- -No radio shielding
- -403 bell housing
- -TI was required on ZR1's in '72, where on standard LT1's it wasn't
Is finding one of these suffixed engines significant? Yes - if it's in a ZR1 with all the other HD bits. Otherwise, I would consider it only "interesting" - but only if it can be proven it was installed on the line. It would be fun to inspect the car to see if there were any other ZR1 indicators - as well as investigating if any "real" ZR1's bracketed the car on the production line, as they often did.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
The ZR1 package also included the M22 tranny and since he says this car still has it's
"numbers matching M21" then that should eliminate this car as being a real ZR1. I guess
it is possible that Flint incorrectly stamped the block but I'm thinking a screwed up restamp.
Any pics of this car or a link to the ad?
Thought it was 70-71 with a shroud and only the 72 without.
TI on a 72? Think it was gone after 71 even on the ZR1.
"numbers matching M21" then that should eliminate this car as being a real ZR1. I guess
it is possible that Flint incorrectly stamped the block but I'm thinking a screwed up restamp.
Any pics of this car or a link to the ad?
Thought it was 70-71 with a shroud and only the 72 without.
TI on a 72? Think it was gone after 71 even on the ZR1.
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
Thought it was 70-71 with a shroud and only the 72 without
p36 "Also a metal fan shroud was fitted to 72 ZR1. The 1970 and'71 examples did not have one."
The article also mentions they used the Aluminum Cross flow that was used in the 65 396/425hp applications and was used during the L88 era.
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 9,127
Likes: 16
From: off leash
St. Jude Donor '21
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 9,127
Likes: 16
From: off leash
St. Jude Donor '21
Quote:
Thought it was 70-71 with a shroud and only the 72 without
Thought it was 70-71 with a shroud and only the 72 without
I got the information from an article in "Vette" magazine January 1990on the 70-72 ZR1, ZR2 Corvettes
p36 "Also a metal fan shroud was fitted to 72 ZR1. The 1970 and'71 examples did not have one."
The article also mentions they used the Aluminum Cross flow that was used in the 65 396/425hp applications and was used during the L88 era.
p36 "Also a metal fan shroud was fitted to 72 ZR1. The 1970 and'71 examples did not have one."
The article also mentions they used the Aluminum Cross flow that was used in the 65 396/425hp applications and was used during the L88 era.
This one has some type of shroud.
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