1968 Engine Code
Thread Starter
Heel & Toe
Joined: Jan 2017
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1968 Engine Code
I have been looking into the HP engine code for 1968 and have seen a few different answers online about which engine it represents. Could someone help clarify if it's 300hp or 350hp (w/ AC, PS and 4 Speed)? Appreciate the guidance.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
350hp with manual trans, factory AC, and power steering. The 3 speed manual was standard. Offhand, I can't recall whether the 350hp option required a four speed.
Last edited by Easy Mike; Dec 28, 2017 at 01:56 PM.
Team Owner
Joined: Sep 2006
Posts: 31,283
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From: Westminster Maryland
Hi Matt and EM,
Yes, 350 h.p..
The wording in the 68-69 TIM&JG indicates that the 3-speed transmission was only available with the 'base' engine during the 68 and 69 model years.
I'd think this means that the 4-speed transmission option would need to be selected when the 350 h.p. engine was selected as an option.
Regards,
Alan
Yes, 350 h.p..
The wording in the 68-69 TIM&JG indicates that the 3-speed transmission was only available with the 'base' engine during the 68 and 69 model years.
I'd think this means that the 4-speed transmission option would need to be selected when the 350 h.p. engine was selected as an option.
Regards,
Alan
Last edited by Alan 71; Dec 28, 2017 at 02:08 PM.
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
I thought the engine suffix code of HP is for the 300 horse engine and that HT was the 350. Or are you not talking about codes? (plus a/c, power steering and manual)
Last edited by 68/BB; Dec 28, 2017 at 02:41 PM.
Burning Brakes
Joined: Sep 2005
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From: Goose Creek SC
http://repairs.willcoxcorvette.com/1...e-block-codes/
Last edited by 68/BB; Dec 28, 2017 at 02:48 PM.
Team Owner
Joined: Sep 2006
Posts: 31,283
Likes: 4,374
From: Westminster Maryland
Hi 68,
What year is your car? 68 or 69?
I believe the HP suffix code was used on 5 engine configurations:
1965 327/300 Corvette
1966 327/350 Corvette
1967 327/350 Corvette
1968 327/350 Corvette
1969 350/300 Passenger Car
Regards,
Alan
This info is from the 4th Edition of the Lime Book.
What year is your car? 68 or 69?
I believe the HP suffix code was used on 5 engine configurations:
1965 327/300 Corvette
1966 327/350 Corvette
1967 327/350 Corvette
1968 327/350 Corvette
1969 350/300 Passenger Car
Regards,
Alan
This info is from the 4th Edition of the Lime Book.
Last edited by Alan 71; Dec 28, 2017 at 03:48 PM.
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Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
Hi 68,
What year is your car? 68 or 69?
I believe the HP suffix code was used on 5 engine configurations:
1965 327/300 Corvette
1966 327/350 Corvette
1967 327/350 Corvette
1968 327/350 Corvette
1969 350/300 Passenger Car
Regards,
Alan
This info is from the 4th Edition of the Lime Book.
What year is your car? 68 or 69?
I believe the HP suffix code was used on 5 engine configurations:
1965 327/300 Corvette
1966 327/350 Corvette
1967 327/350 Corvette
1968 327/350 Corvette
1969 350/300 Passenger Car
Regards,
Alan
This info is from the 4th Edition of the Lime Book.
Last edited by 68/BB; Dec 28, 2017 at 08:01 PM.
Racer
Joined: Jan 2016
Posts: 290
Likes: 78
GM Heritage site has a bunch of info including code and date deciphers.
https://gmheritagecenter.com/index.html
https://gmheritagecenter.com/index.html
Thread Starter
Heel & Toe
Joined: Jan 2017
Posts: 22
Likes: 1
GM Heritage site has a bunch of info including code and date deciphers.
https://gmheritagecenter.com/index.html
https://gmheritagecenter.com/index.html
Safety Car
Joined: May 2008
Posts: 3,753
Likes: 721
From: Lafayette Louisiana
Imo,....
For the 1968 Corvette, from what I can discover, there are a lot of sources that call the HP a 300hp and others that call the 68 Corvette HP a 350hp.
Both the 3rd (2001) and 4th edition (2012) of the NCRS 68-69 Technical Information Manual and Judging Guide has the 68 Corvette HP as 350hp.
I have another NCRS pocket sized 68 to 82 Corvette Specification Guide vol 2 dated Spring 1997 that has the HP as 300hp.
So there has been confusion on this, likely due to the multible HP designations as Alan said.
However, my money is on the latest NCRS 4th edition (do not have the 5th edition yet) with the HP as 350hp as being correct.
My question is still if the 68 Corvette HP and HT are both 350hp, why is the HT shown with a "special cam" as you would think the HP has the special cam too along with manual trans, P/S and A/C???
Both the 3rd (2001) and 4th edition (2012) of the NCRS 68-69 Technical Information Manual and Judging Guide has the 68 Corvette HP as 350hp.
I have another NCRS pocket sized 68 to 82 Corvette Specification Guide vol 2 dated Spring 1997 that has the HP as 300hp.
So there has been confusion on this, likely due to the multible HP designations as Alan said.
However, my money is on the latest NCRS 4th edition (do not have the 5th edition yet) with the HP as 350hp as being correct.
My question is still if the 68 Corvette HP and HT are both 350hp, why is the HT shown with a "special cam" as you would think the HP has the special cam too along with manual trans, P/S and A/C???
Race Director
Joined: Oct 2000
Posts: 12,683
Likes: 3,137
From: Shamong, NJ
I believe that the 68 "HP" code is a 327/300 with AC, and power steering.
My 1970 Corvette Parts Book lists the 68 327 codes as follows:
HE - 327 with Manual Trans.
HO - 327 with 3-speed Automatic Trans
HP - 327 with Hyd. Steering and C.A.C.
(In the parts book Hyd. Steering is power steering and C.A.C. is car air conditioning)
HT - 327 Special High Performance
In the parts book, all 327/300's either carry no designation, or are referred to as "High Performance", while 327/350's are always listed as "Special High Performance".
If HP was a 327/350 with PS and AC, the parts book would have listed it as Spec. High Perf., Hyd. Steering & C.A.C. Since the parts book doesn't list the HP as "Special High Performance", I have to believe that HP was the base 327/300 engine.
Which heads are on the engine? "291" were used on 300's and 350's, but "292" heads were only used on the 350 horse. Is there any chance that the carb is original? The 327/300 manual trans used Q-Jet 7028207, while the 327/350 used Q-Jet 7028219. If the car has it's original distributor, the part number would be 1111194 for a 327/300, and either 1111438, 441 or 475 for a 327/350.
My 1970 Corvette Parts Book lists the 68 327 codes as follows:
HE - 327 with Manual Trans.
HO - 327 with 3-speed Automatic Trans
HP - 327 with Hyd. Steering and C.A.C.
(In the parts book Hyd. Steering is power steering and C.A.C. is car air conditioning)
HT - 327 Special High Performance
In the parts book, all 327/300's either carry no designation, or are referred to as "High Performance", while 327/350's are always listed as "Special High Performance".
If HP was a 327/350 with PS and AC, the parts book would have listed it as Spec. High Perf., Hyd. Steering & C.A.C. Since the parts book doesn't list the HP as "Special High Performance", I have to believe that HP was the base 327/300 engine.
Which heads are on the engine? "291" were used on 300's and 350's, but "292" heads were only used on the 350 horse. Is there any chance that the carb is original? The 327/300 manual trans used Q-Jet 7028207, while the 327/350 used Q-Jet 7028219. If the car has it's original distributor, the part number would be 1111194 for a 327/300, and either 1111438, 441 or 475 for a 327/350.
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
I believe that the 68 "HP" code is a 327/300 with AC, and power steering.
Which heads are on the engine? "291" were used on 300's and 350's, but "292" heads were only used on the 350 horse. Is there any chance that the carb is original? The 327/300 manual trans used Q-Jet 7028207, while the 327/350 used Q-Jet 7028219. If the car has it's original distributor, the part number would be 1111194 for a 327/300, and either 1111438, 441 or 475 for a 327/350.
Which heads are on the engine? "291" were used on 300's and 350's, but "292" heads were only used on the 350 horse. Is there any chance that the carb is original? The 327/300 manual trans used Q-Jet 7028207, while the 327/350 used Q-Jet 7028219. If the car has it's original distributor, the part number would be 1111194 for a 327/300, and either 1111438, 441 or 475 for a 327/350.
BTW, I don't have original carb on mine (about the only thing on the engine that isn't), however, I'm sure it has original camshaft. When the restoration was started by PO he had the engine rebuilt and the paperwork he gave me shows minimal parts change was required. It still has original bore and pistons. I really don't want to pull that engine out of storage and pull that cam but.......
Last edited by 68/BB; Dec 29, 2017 at 08:46 AM.
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
My coupe was highly optioned with AC, power steering and brakes, power windows, tele steering col, etc...makes sense that it would not have base engine I suppose. Hmmmm, I may have to rethink my opinion. However, it is odd that there is so much conflicting information on this...just another '68 "curse" I guess. Any chance it may have been a running change in the model year? I would really not think so, that just wouldn't make sense.
