1968 Correct Engine suffix code
Team Owner
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From: Crossville TN
Both HP and HT could be used for the 327/350hp engine. HT was applied for manual transmission car without A/C and/or Power Steering. If the car received A/C and/or P/S, the engine got the HP code.
CF Community Team
Joined: Mar 2007
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From: Delaware
St. Jude Donor '25
This one I know. There is a lot of bad info out there on 68 codes on different sites.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
Thread Starter
Instructor
Joined: Sep 2007
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Thread Starter
Instructor
Joined: Sep 2007
Posts: 227
Likes: 8
This one I know. There is a lot of bad info out there on 68 codes on different sites.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
Race Director
Joined: Oct 2000
Posts: 12,682
Likes: 3,135
From: Shamong, NJ
This one I know. There is a lot of bad info out there on 68 codes on different sites.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
HT is 327-350hp WITHOUT AC
HP is 327-350hp WITH AC
I have owned my L79 (HT)since 1985. NO AC. I also had an L79 (HP) WITH AC and no PS. I believe the current judging manual has it right. HP code is not shared with any 300hp car in 68.
I know the Corvette Parts Books were always vague about this, only saying 327 with Hyd. Steering & C.A.C. (car air conditioning) - HP, and 327 with Special High Performance - HT, but the NCRS has always listed HP as a 300 horse and HT as 350 horse. I have at least 3 NCRS books, going all the way back to the 1989 Restorer 15th Anniversary Edition, 1953-1972 Specifications Guide, that all show "HP" as a 300 with AC and "HT" as the 327/350?
I don't have a need for it, so I don't have a current 68-69 Judging Manual. I think there may now be a 5th Edition of the pocket size, 68-82 Specifications Guide, I guess I'll have to get one to replace my 4th Edition one!
CF Community Team
Joined: Mar 2007
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From: Delaware
St. Jude Donor '25
hi,
Not sure when NCRS made the correction but pretty sure the latest edition is correct. I was also going by the L79 I own and the other I did own. My longtime L79 is a non AC (HT) and the other ( also very orig 50k mile 1 owner) was an AC L79 ( HP).
Not sure when NCRS made the correction but pretty sure the latest edition is correct. I was also going by the L79 I own and the other I did own. My longtime L79 is a non AC (HT) and the other ( also very orig 50k mile 1 owner) was an AC L79 ( HP).
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Burning Brakes
Joined: Feb 2008
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From: Lincoln NE Riding and Driving Corvettes since 1967.
I own a 1968 L79 with factory A/C no power steering.
The original Flint yellow grease pencil markings are visible on both sides of the engine block and are "HT"
The engine ID pad is also stamped HT
Bigredbrad
The original Flint yellow grease pencil markings are visible on both sides of the engine block and are "HT"
The engine ID pad is also stamped HT
Bigredbrad
CF Community Team
Joined: Mar 2007
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From: Delaware
St. Jude Donor '25
Ok, that is strange. Do you have a build sheet? Any pics of the AC set up?
Burning Brakes
Joined: Feb 2008
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From: Lincoln NE Riding and Driving Corvettes since 1967.
CF Community Team
Joined: Mar 2007
Posts: 9,329
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From: Delaware
St. Jude Donor '25
Next question. The L79 C60 (HP) I had was a very late car ( Aug 68). I did not have a build sheet but I had the original window sticker and dealer paperwork. Is you car on the other end of production (early)? Just trying to figure out if the factory changed the suffix at some point.
Thanks for the info. Have a great weekend! AJ
Burning Brakes
Joined: Feb 2008
Posts: 826
Likes: 119
From: Lincoln NE Riding and Driving Corvettes since 1967.
Wow,
Next question. The L79 C60 (HP) I had was a very late car ( Aug 68). I did not have a build sheet but I had the original window sticker and dealer paperwork. Is you car on the other end of production (early)? Just trying to figure out if the factory changed the suffix at some point.
Thanks for the info. Have a great weekend! AJ
Next question. The L79 C60 (HP) I had was a very late car ( Aug 68). I did not have a build sheet but I had the original window sticker and dealer paperwork. Is you car on the other end of production (early)? Just trying to figure out if the factory changed the suffix at some point.
Thanks for the info. Have a great weekend! AJ
Yes, this particular car is a December 67 build.
I also have a March built 1968 L79 AC and I will try and look to see if it is HP or HT
Have you done a survey of vins to determine if there is a pattern or have you started to determine a date change from HT to HP?
I have been doing research on 1968 fan shroud and radiator usage with C60 A/C option. Maybe we should collaborate our information?
Bigredbrad
Drivers Side Flint HT markings under original paint
Passenger side Flint HT markings two times under paint. Also was marked HT on the end of one head but I cant find that photo right now.
