1969 427 engine code question
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Joined: Dec 2024
Posts: 66
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From: Mendocino County, California
1969 427 engine code question
I found a car that has a 427 with stamp code LP. It has OE alum gm heads. I think this is a L89? It currently has a single quad, but the code indicates it had 3x2bbl?
Any help is appreciated.
Any help is appreciated.
Thread Starter
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Joined: Dec 2024
Posts: 66
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From: Mendocino County, California
Matching?
Thanks for the response. No. The vin does NOT match. It's a transplant. I have a pic, but I haven't purchased the car yet?? I'll ask and see if I can post. The owner is selling as a transplant.
Drifting
Joined: Sep 2016
Posts: 1,489
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From: Ventura California
I see you are in Northern CA.
What is the casting date of the block and according to the engine pad, when was the engine built?
What does the console data plate say?
You should also reach out to DKM-106. He has the L89 registry for 67-68-69. He can tell you all you want to know about either the engine or car if it’s a real L89.
What is the casting date of the block and according to the engine pad, when was the engine built?
What does the console data plate say?
You should also reach out to DKM-106. He has the L89 registry for 67-68-69. He can tell you all you want to know about either the engine or car if it’s a real L89.
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From: Mendocino County, California
Bummer
I found similar info. 842s are 68/early 69 L88/L89 closed chamber heads (109cc)
074s are late 69 L88/L89/ZL1 and 70/71 LS6/LS7 open chamber (118cc)
Personally I prefer closed chamber on lower hp engines (under 600hp) and smaller bore <=4.25in
i use open chamber heads on big hp bb motors especially like 4.600in bore.
I was curious what the 69 L89 vette used. Thank you for clearing it up!
074s are late 69 L88/L89/ZL1 and 70/71 LS6/LS7 open chamber (118cc)
Personally I prefer closed chamber on lower hp engines (under 600hp) and smaller bore <=4.25in
i use open chamber heads on big hp bb motors especially like 4.600in bore.
I was curious what the 69 L89 vette used. Thank you for clearing it up!
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Safety Car
Joined: May 2001
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From: Fairfax Virginia
I have a set of the 3931063 cast iron cylinder heads that are Closed Chamber heads used in the 1968 BB engines. They were cast in 8/67 for a car built in October 1967 and fit the L88 piston crowns perfectly. The only drawback is they are only 100.9cc but that makes them perfect for a High Compression engine.
These are good heads as they flow pretty well and they don't detonate like the open chamber heads can and do. We built them both after some clean up was done inside the heads from the bare head to a finished product with all new parts.
These are good heads as they flow pretty well and they don't detonate like the open chamber heads can and do. We built them both after some clean up was done inside the heads from the bare head to a finished product with all new parts.
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
Go into the search with the lowest of hopes though... a "blown" engine back in the day, if it was salvageable, was likely decked sometime in it's journey, removing all identifying information.
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Joined: Nov 2023
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From: Florida
I know mine was traded for a 327, then went through a couple different owners and I came to a dead end when one guys wife didn’t know what happened to it and he was dead…that’s where my search ended many, many years ago.
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From: Mendocino County, California
I don't have the car vin or the motor vin. Seller didn't offer, but I get them along with the trim tag. In the big picture, if its not a number matching car, i guess i can build a modern motor and slide it into any BB car. How bad is that? I prefer to find a real car, that will keep me from tinkering with the drive train
Safety Car
Joined: Dec 1999
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From: PA
I found similar info. 842s are 68/early 69 L88/L89 closed chamber heads (109cc)
074s are late 69 L88/L89/ZL1 and 70/71 LS6/LS7 open chamber (118cc)
Personally I prefer closed chamber on lower hp engines (under 600hp) and smaller bore <=4.25in
i use open chamber heads on big hp bb motors especially like 4.600in bore.
I was curious what the 69 L89 vette used. Thank you for clearing it up!
074s are late 69 L88/L89/ZL1 and 70/71 LS6/LS7 open chamber (118cc)
Personally I prefer closed chamber on lower hp engines (under 600hp) and smaller bore <=4.25in
i use open chamber heads on big hp bb motors especially like 4.600in bore.
I was curious what the 69 L89 vette used. Thank you for clearing it up!
3904392 - Used on all 1967 L-88 engines
Used on all 1967 L-89 engines
3919842 - Used on all 1968 L-88 engines
Used on all 1968 L-89 engines
Used on early 1969 L-88 engines
Used on all 1969 L-89 engines
Used on all 1970 L-89 engines (early L-78 Chevelles only)
Would also have been used on all 1970 LS-7 Corvette engines had it been built.
3946074 - Used on late 1969 L-88 engines
Used on all 1969 ZL-1 engines
Used on all 1971 LS-6 engines
Chevrolet always listed their closed chamber aluminum head volume as roughly 106 cc and the closed chamber cast iron head volume at roughly 109 cc, but the fact is that these numbers were nominal and were probably very close in actual practice.
Regards,
Stan Falenski
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Joined: Dec 2024
Posts: 66
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From: Mendocino County, California
Thank you
Early big block Chevrolet aluminum head usage is as follows:
3904392 - Used on all 1967 L-88 engines
Used on all 1967 L-89 engines
3919842 - Used on all 1968 L-88 engines
Used on all 1968 L-89 engines
Used on early 1969 L-88 engines
Used on all 1969 L-89 engines
Used on all 1970 L-89 engines (early L-78 Chevelles only)
Would also have been used on all 1970 LS-7 Corvette engines had it been built.
3946074 - Used on late 1969 L-88 engines
Used on all 1969 ZL-1 engines
Used on all 1971 LS-6 engines
Chevrolet always listed their closed chamber aluminum head volume as roughly 106 cc and the closed chamber cast iron head volume at roughly 109 cc, but the fact is that these numbers were nominal and were probably very close in actual practice.
Regards,
Stan Falenski
3904392 - Used on all 1967 L-88 engines
Used on all 1967 L-89 engines
3919842 - Used on all 1968 L-88 engines
Used on all 1968 L-89 engines
Used on early 1969 L-88 engines
Used on all 1969 L-89 engines
Used on all 1970 L-89 engines (early L-78 Chevelles only)
Would also have been used on all 1970 LS-7 Corvette engines had it been built.
3946074 - Used on late 1969 L-88 engines
Used on all 1969 ZL-1 engines
Used on all 1971 LS-6 engines
Chevrolet always listed their closed chamber aluminum head volume as roughly 106 cc and the closed chamber cast iron head volume at roughly 109 cc, but the fact is that these numbers were nominal and were probably very close in actual practice.
Regards,
Stan Falenski
Thank you for that. You nailed it.
