What engine 1970 ??
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Intermediate
Joined: Nov 2008
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What engine 1970 ??
I'm just curious and maybe baffled ,maybe just a thought that persists in the back of my mind ,maybe it means nothing.
I have a 1970 ,it's been with me a long freaking time and I have always had this thought in the back of my mind about the original engine .
Twenty five years ago I pulled the engine and had it rebuilt and the builder decked the top and asked if I wanted the # re stamped on the plate , after some investigation we found the block was ten months newer then the car {casting date code} and it was an 010 block . At the time all this stuff was irrelevant and I didn't give a damn so nothing was done sense it wasn't the original block.
The question I have is that it was built as if it was an L-46 350/350 and it might have been a base 300 hp vette ,how do I tell ,what are the little things that would say it is one or the other ? No tank sticker was found ,and I'm just for a loss on this one .Every L-46 I have seen are pretty much the same but my car is a no powered accessory car.
I have a 1970 ,it's been with me a long freaking time and I have always had this thought in the back of my mind about the original engine .
Twenty five years ago I pulled the engine and had it rebuilt and the builder decked the top and asked if I wanted the # re stamped on the plate , after some investigation we found the block was ten months newer then the car {casting date code} and it was an 010 block . At the time all this stuff was irrelevant and I didn't give a damn so nothing was done sense it wasn't the original block.
The question I have is that it was built as if it was an L-46 350/350 and it might have been a base 300 hp vette ,how do I tell ,what are the little things that would say it is one or the other ? No tank sticker was found ,and I'm just for a loss on this one .Every L-46 I have seen are pretty much the same but my car is a no powered accessory car.
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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doesn't your car still have the emissions decal on the firewall, and the engine data plate on the console. what RPM reading is on the tach. that's 3 good places to start
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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if your block was replaced under warranty and they only replaced the block they would have reused the top half of the engine. like the heads, intake, carb, distributor, and the exhaust manifolds. if so if they are dated before the car chance are they are original to your car. so there are more clues for you.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Hello; I have 2 L46 cars. I would believe your data plate would be correct, who would change it out 25 years ago? A check on the '70 registry gives us a few quick check points. If your distributor is the original, is the last # a 0, or 1 (L46)? Another difference is radiators. base engine came with aluminum (assuming no A/C) with a surge tank. L46 cars came with a copper radiator, and no surge. Your 6k red line is correct. If you haven't checked the registry, here's a link. Good Luck
http://www.1970corvetteregistry.org/codes.html
http://www.1970corvetteregistry.org/codes.html
Thread Starter
Intermediate
Joined: Nov 2008
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Thanks Dave & Nowhere ,seems things are all pointing to the L46 for sure .I'm pretty new here and very impressed with the people .
I just had to get this off my chest once and for good . I'm finally back into the vette thing ,no more Porsche's ,Maybe I shouldn't mentioned that name brand ,Ha Ha .
I always wondered way this car didn't have an expansion tank ,makes sense now .
I just had to get this off my chest once and for good . I'm finally back into the vette thing ,no more Porsche's ,Maybe I shouldn't mentioned that name brand ,Ha Ha .
I always wondered way this car didn't have an expansion tank ,makes sense now .
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
if your block was replaced under warranty and they only replaced the block they would have reused the top half of the engine. like the heads, intake, carb, distributor, and the exhaust manifolds. if so if they are dated before the car chance are they are original to your car. so there are more clues for you.
I see 3 listings as follows from the corvette action center site and Corvette by the Numbers:
For 300, 350, 370 hp-3927186 (Corvette by the Numbers)
For 350 hp-3927187
For 370 hp-3973414
You should also see the casting dates
Carb ID#'s
300 hp -manual-7040203 first design
300 hp -manual-7040213 second design
350 hp- manual-7040207
intake casting-3965577-(Corvette by the Numbers)
Tach 300hp redline @ 5300 rpm
Tach 350hp redline @ 6000 rpm
Hope this helps.
Glenn
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Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
Hello; I have 2 L46 cars. I would believe your data plate would be correct, who would change it out 25 years ago? A check on the '70 registry gives us a few quick check points. If your distributor is the original, is the last # a 0, or 1 (L46)? Another difference is radiators. base engine came with aluminum (assuming no A/C) with a surge tank. L46 cars came with a copper radiator, and no surge. Your 6k red line is correct. If you haven't checked the registry, here's a link. Good Luck
http://www.1970corvetteregistry.org/codes.html
http://www.1970corvetteregistry.org/codes.html
Thread Starter
Intermediate
Joined: Nov 2008
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Good question GD ,I am thinking of putting one on anyways ,seems in the summer in hot weather theres some coolant getting past the cap and an expansion tank would keep this from happening . Just a thought .
Drifting
Joined: Sep 1999
Posts: 1,970
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When I bought my vette 2 years ago, I thought it was originally an L-46. Data plate indicates this. Original motor is long gone. It has a surge tank and had a aluminum radiator, original also been replaced. In a post I asked for pics of original L-46 engine bays, and some pics had surge tanks and others didn't. Was there a variation at the factory with the cooling systems?
Last edited by dennis; Jan 17, 2009 at 05:44 PM.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
When I bought my vette 2 years ago, I thought it was originally an L-46. Data plate indicates this. Original motor is long gone. It has a surge tank and had a aluminum radiator, original also been replaced. In a post I asked for pics of original L-46 engine bays, and some pics had surge tanks and others didn't. Was there a variation at the factory with the cooling systems?
I am by no way an expert in this area, but it holds my interest. These cars were all unique I believe. There were many changes throughout the model year, reflecting the times. Maybe Dennis will chime in here.
Drifting
Joined: Oct 2008
Posts: 1,369
Likes: 12
From: wichita kansas
maivette....it is very possible that the block that is in your car is indeed the original engine. the mechanic years ago may have misread the casting date on the engine, they can be difficult to read at times OR if the casting date actually is aprox 10 months earlier than the build date of your car, that is still a real possibility. (although uncommon for components to pre-date the car that much, but it has been documented on other cars to have happened)
can you read the date casting on the block? if so, what are the numbers and letters? (it would be located on top rear of right side of block just behind the right hand head)
can you read the date casting on the block? if so, what are the numbers and letters? (it would be located on top rear of right side of block just behind the right hand head)
Drifting
Joined: Oct 2008
Posts: 1,369
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From: wichita kansas
Thread Starter
Intermediate
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Sorry ,the car is buried under all my wife's pool crap and it's like 12 degrees out there ,I'm a couch tator today . I was lucky to get the drivers door open earlier today ,screw it ,I'll get back to ya on that one . I might have it wrote down here some where .
Intermediate
Joined: Nov 2008
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From: Sonora CA
More Year I.D. confusion...
My '69 Assembly Manual shows an Aluminum rad with no pressure cap (p. J257) and a two-piece metal fan shroud (J258 with spot welds). Page J259 shows a pressurized aluminum surge tank. MY '69 (350/300) has a copper rad AND a surge tank. Go figure.
