Vintage_barry Posted January 31, 2019 Share Posted January 31, 2019 Does anyone have photos and location of the factory “MZ” stamp on the 1966 Riviera 425 engine blocks? I’ve read and heard about but can’t find any pictures. Thanks for any help, Barry Link to comment Share on other sites More sharing options...
JZRIV Posted January 31, 2019 Share Posted January 31, 2019 (edited) Barry, I'm sure there is a pic out there in cyber world somewhere. One reason its hard to find is only a handful are known to exist and owners of those that do aren't enthusiastic about publicizing the engine stamp on the internet due to risk of cloning. Are you looking at a specific car and need confirmation? Attached is a pic of a 65 LX stamp from a GS. Same general location typical of all nailheads in this era only an M and Z instead of LX Edited January 31, 2019 by JZRIV (see edit history) 1 Link to comment Share on other sites More sharing options...
RivNut Posted January 31, 2019 Share Posted January 31, 2019 Here's an illustration that shows the location of the Engine Production Code (the MZ you're looking for) and the Engine Serial Number (which matches the VIN) Most of the time the code will be facing you rather than away from you as shown in the illustration. Link to comment Share on other sites More sharing options...
Vintage_barry Posted January 31, 2019 Author Share Posted January 31, 2019 Thanks for your replies. I’m interested in purchasing a 66 GS and while I’m doing my research I kept coming across the MZ code and wanted to see a picture but there none on the net. Hope to see you guys in Gettysburg this June. Bring me a 66 Riviera GS to buy or drool over. Regards, Barry Link to comment Share on other sites More sharing options...
RivNut Posted January 31, 2019 Share Posted January 31, 2019 Barry, The MZ code engine was installed in 179 Rivieras toward the end of the production year in 1966. BUT the Grans Sport was available from the beginning of the year. The dual four barrel set up came in the trunk and was installed at the dealership. So you can find an authentic 1966 Gran Sport with a MW coded engine in it. Link to comment Share on other sites More sharing options...
JZRIV Posted January 31, 2019 Share Posted January 31, 2019 42 minutes ago, Vintage_barry said: Thanks for your replies. I’m interested in purchasing a 66 GS and while I’m doing my research I kept coming across the MZ code and wanted to see a picture but there none on the net. Hope to see you guys in Gettysburg this June. Bring me a 66 Riviera GS to buy or drool over. Regards, Barry What is your budget Barry? Link to comment Share on other sites More sharing options...
Vintage_barry Posted January 31, 2019 Author Share Posted January 31, 2019 Trick question? In the teens. Looking for a 66 Riviera GS, solid driver, bucket seats, power windows, a/c and I live in Maryland. Regards, Barry 1 Link to comment Share on other sites More sharing options...
1965rivgs Posted January 31, 2019 Share Posted January 31, 2019 2 hours ago, RivNut said: Barry, The MZ code engine was installed in 179 Rivieras toward the end of the production year in 1966. BUT the Grans Sport was available from the beginning of the year. The dual four barrel set up came in the trunk and was installed at the dealership. So you can find an authentic 1966 Gran Sport with a MW coded engine in it. Ed, The MZ cars were available starting at approximately Feb 1st, 1966 so well before the end of the model year. Do you have any documentation as to the dual quad systems being placed in the trunk? Tom Link to comment Share on other sites More sharing options...
RivNut Posted January 31, 2019 Share Posted January 31, 2019 1 hour ago, 1965rivgs said: Ed, The MZ cars were available starting at approximately Feb 1st, 1966 so well before the end of the model year. Do you have any documentation as to the dual quad systems being placed in the trunk? Tom I thought is was closer to April, but... Just what the gurus have told me. Link to comment Share on other sites More sharing options...
1965rivgs Posted January 31, 2019 Share Posted January 31, 2019 1 hour ago, RivNut said: I thought is was closer to April, but... Just what the gurus have told me. Ooops, Ed, I may have mislead in my post...the cars are generally thought to have been available March 1st, 1966 but my MZ car has a body build mid-Feb and so would have likely been assembled in the month of February. It was ordered by and delivered to Peck Buick in San Diego, CA so would likely have been delivered to the dealer by March 1st. I believe the MZ car I own may have been one of the first few cars built. Tom Link to comment Share on other sites More sharing options...
Chimera Posted February 1, 2019 Share Posted February 1, 2019 19 hours ago, 1965rivgs said: Ooops, Ed, I may have mislead in my post...the cars are generally thought to have been available March 1st, 1966 but my MZ car has a body build mid-Feb and so would have likely been assembled in the month of February. It was ordered by and delivered to Peck Buick in San Diego, CA so would likely have been delivered to the dealer by March 1st. I believe the MZ car I own may have been one of the first few cars built. Tom Tom, what color is your MZ? Dual Quads on a 66 are sweeeet! yeah, they always say the first week in March MZ started, but some had a late Feb. date code. Perhaps what is meant is that they delivered to dealer as of March 1st available to the public as Tom mentioned. That makes sense. 2 Link to comment Share on other sites More sharing options...
1965rivgs Posted February 1, 2019 Share Posted February 1, 2019 25 minutes ago, Chimera said: Tom, what color is your MZ? Dual Quads on a 66 are sweeeet! yeah, they always say the first week in March MZ started, but some had a late Feb. date code. Perhaps what is meant is that they delivered to dealer as of March 1st available to the public as Tom mentioned. That makes sense. Black in and out Tom 3 Link to comment Share on other sites More sharing options...
telriv Posted February 1, 2019 Share Posted February 1, 2019 I think he means the color of the engine Tom. Tom T. Link to comment Share on other sites More sharing options...
65VerdeGS Posted February 1, 2019 Share Posted February 1, 2019 On a side note, why do '66 Gran Sport cars with aluminum valve covers have a 'dent' in the left hand cover? Was this to provide clearance for an AIR (Air Injection Reactor) pump? I've yet to see a '66 GS with an AIR pump in place. I realize many such systems were removed over the years as they were often detrimental to engine performance. As far as I know, the AIR system was only mandatory in California in 1966, making this an extra-cost option in all other 49 states (and Canada). I can't see anyone back then paying $40+ for an AIR system. Anyone remotely environmentally conscious probably wouldn't be buying a big block Buick car anyway 😳 So, did only '66 Gran Sports sold new in California come with AIR? What about the standard Rivieras? Did they also come equipped with AIR in California? Did 49-state cars have the non-dented valve covers? If so, the dented valve cover would an indication that the car may have been sold new in California, correct? Link to comment Share on other sites More sharing options...
1965rivgs Posted February 1, 2019 Share Posted February 1, 2019 (edited) 2 hours ago, 65VerdeGS said: On a side note, why do '66 Gran Sport cars with aluminum valve covers have a 'dent' in the left hand cover? Was this to provide clearance for an AIR (Air Injection Reactor) pump? I've yet to see a '66 GS with an AIR pump in place. I realize many such systems were removed over the years as they were often detrimental to engine performance. As far as I know, the AIR system was only mandatory in California in 1966, making this an extra-cost option in all other 49 states (and Canada). I can't see anyone back then paying $40+ for an AIR system. Anyone remotely environmentally conscious probably wouldn't be buying a big block Buick car anyway 😳 So, did only '66 Gran Sports sold new in California come with AIR? What about the standard Rivieras? Did they also come equipped with AIR in California? Did 49-state cars have the non-dented valve covers? If so, the dented valve cover would an indication that the car may have been sold new in California, correct? Yes, to clear the A.I.R. pump. Yes, mandatory in CA except on low volume situations...like the MZ cars. All `66 Riv GS and Wildcat GS cars have the same valve cover. Best indication of an original CA car is the closed PCV system, although it was optional in other locations. New York state was pretty aggresive re pollution control devices back in the day so it would not surprise me if they were also in the mix regarding some of the early pollution control systems. I know they were also involved in the closed PCV system earlier than most states. Tom Edited February 2, 2019 by 1965rivgs (see edit history) Link to comment Share on other sites More sharing options...
RivNut Posted February 2, 2019 Share Posted February 2, 2019 1 hour ago, telriv said: I think he means the color of the engine Tom. Tom T. If this is the question, the Riviera had a red nailhead. The Skylark GS also had a red 401 in '66. Link to comment Share on other sites More sharing options...
JZRIV Posted February 3, 2019 Share Posted February 3, 2019 On 2/1/2019 at 6:37 PM, 65VerdeGS said: I've yet to see a '66 GS with an AIR pump in place. Indeed uncommon to see a fully functioning system intact like this one I photographed at the ROA meet in Monterey CA in 2012 Link to comment Share on other sites More sharing options...
johnrex Posted February 4, 2019 Share Posted February 4, 2019 Here is another shot of the 1966 air pump taken at Monterey in 2009 Link to comment Share on other sites More sharing options...
65VerdeGS Posted February 6, 2019 Share Posted February 6, 2019 Thanks John and Jason for sharing photos of the AIR system on '66 Rivs. Indeed pretty rare to see a complete system. I've never seen one on a '66 Riv, but did notice plenty with that dimpled aluminum valve cover. As with other performance cars of the era, it appears most owners removed the air pump and mess of hoses and tubes as soon as they got the chance. Did the AIR system affect driveability that much? Of course it would have added a bit of extra weight. I've also heard that the air pumps could be noisy. But was the system that detrimental to the engine's operation? Did it contribute to overheating? Stalling? I guess one benefit would be that the exhaust system would run hotter, so maybe the pipes and muffler would last longer? My '65 was notorious for rotting out that big transverse rear muffler on a regular basis... Link to comment Share on other sites More sharing options...
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