1970 Corvette LT1 question
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3rd Gear
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1970 Corvette LT1 question
I apologize if this has been asked before. I have a 1970 Corvette that is supposed to be a LT1. I know these are often not LT1's and there is list of things to go through to authenticate. I just got the car and the engine number matches the Vin and has the CTK engine code. Do I need to go further or is this enough to designate a LT1?
1967 Pedal Car Champion
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From: US-PNW
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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Wow that is bad. Factory stamps where done in a gang holder where it will be straight and even. That is not even close
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From: Anaheim Hills California
I'm sorry to be the bearer of bad news but in my 44 years as a Corvette mechanic I have never seen a stamping like that come out of the factory. As Nowhere Man stated they are done with a gang holder and I've seen them off center of the pad but still in line. Those numbers are all over the place. Also the font looks a little funky to me.
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1967 Pedal Car Champion
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From: US-PNW
Keep in mind that the very poor restamping does not tell you that it's not the original block/engine for the car. Could very well be original and just restamped after block was decked (though it looks like it's been ground out and not done by a machined fly-cutter or the like which is suspicious in itself).
Your next step is to look at both sides of the top of the engine's rear flange where it bolts to the transmission. The driver's side should have the block's casting #, the passenger side should have the casting date.
Your next step is to look at both sides of the top of the engine's rear flange where it bolts to the transmission. The driver's side should have the block's casting #, the passenger side should have the casting date.
Le Mans Master
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From: LONG ISLAND
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OMG ................sorry, but that's the worst stamp pad I have ever seen, no question, hands down, PERIOD !! It's like the difference between a five year olds handwriting and an adult. BAD ....... Hope you didn't pay LT-1 money for it !!!
Race Director
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Have you removed a valve cover to check for screw in rocker studs with guide plates,?
Have you looked at the metal fuel line on the frame near the fuel pump? There should be only one 3/8" line. If there is a second smaller line, never was an LT1.
Have you looked at the metal fuel line on the frame near the fuel pump? There should be only one 3/8" line. If there is a second smaller line, never was an LT1.
Pro
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From: Vancouver B.C.
As mentioned, the original block could have been decked and someone tried to restamp it. Other clues if it is an LT1, and I assume your car is a 4 speed:
- single fuel line. No return
- 6500 rpm tach redline
- copper rad. No aluminum overflow tank and no holes where one could have been mounted.
- Transistor ignition. Look for box on driver side inner fender.
- half shaft retainers should have caps with bolts. Not U bolts with nuts
- Winters intake manifold 3972110
- 8” balancer on crank
- single fuel line. No return
- 6500 rpm tach redline
- copper rad. No aluminum overflow tank and no holes where one could have been mounted.
- Transistor ignition. Look for box on driver side inner fender.
- half shaft retainers should have caps with bolts. Not U bolts with nuts
- Winters intake manifold 3972110
- 8” balancer on crank
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