What was my engine!!
Thread Starter
6th Gear
Joined: Aug 2008
Posts: 6
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From: Missouri
What was my engine!!
Is there anyway to tell or get a good idea of what engine was in my 1968 Corvette when it was new. I have a 1970 LT1 from a Z-28 in it now, but I have always wondered what it had when it was born. I do not have a build sheet or window sticker so are the any markings on the rest of the car that might give me a hint.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
Is the original radiator in the car? Big block and AT small block cars got the big 4 row Harrison copper & brass radiators. Base engine and 350hp small block cars usually got the stacked plate aluminum radiator.
Stock rear sway bar in the car? Big block cars got the rear sway bar.
Original transmission in the car? The base three speed and the optional TH400 were not available with certain optional engines.
Can you read the tags on the front springs? There are different codes for small and big block cars.
Granted any and all of the above could have been changed by previous owners, but it gives you a few places to begin your detective work.
The '68 assembly instruction manual (AIM) can help a little. The AIM lists the standard assembly of the cars, plus the option combinations. You can compare what you find on the car with what's in the AIM.
Stock rear sway bar in the car? Big block cars got the rear sway bar.
Original transmission in the car? The base three speed and the optional TH400 were not available with certain optional engines.
Can you read the tags on the front springs? There are different codes for small and big block cars.
Granted any and all of the above could have been changed by previous owners, but it gives you a few places to begin your detective work.
The '68 assembly instruction manual (AIM) can help a little. The AIM lists the standard assembly of the cars, plus the option combinations. You can compare what you find on the car with what's in the AIM.
Pro
Joined: Jul 1999
Posts: 550
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From: smithfield nc usa 27577
Telling if it was a big block or small block is not that hard.
Telling which big block or small block can be very tricky.
Big blocks had bigger fuel lines, different bolts on the half shafts.
Rad support etc. What does your fan shrowd look like?
The thing is now it really does not matter.....an lt 1 motor is a sweet thing and is hard to beat.
Telling which big block or small block can be very tricky.
Big blocks had bigger fuel lines, different bolts on the half shafts.
Rad support etc. What does your fan shrowd look like?
The thing is now it really does not matter.....an lt 1 motor is a sweet thing and is hard to beat.
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Pro
Joined: Nov 2004
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From: Nice Lake Ontario
My 69 BB car was changed from BB hood to SB hood.
Unless 350HP cars came with a big rad, sway bar & U-joint bolts?
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
F-41 could account for the rear sway bar with a small block. The four row Harrison is what is throwing me. I'm thinking the optional 350hp small block required the 4 speed, BUT if you could get the 350 with the TH400 that could account for the 4 row.
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From: Massillon,Ohio USA
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Melting Slicks
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From: Burning Jet-A
Hard and fast, feel under the passenger side framerail for the fuel line. Single line 427/400 or 435. If it is not, then the dual line, 1 fuel and 1 vapor return mean its a non Holley car. It still could be a 427/390 if big blocks are the thing, so look at the rear end. If the halfshafts are held to the differential yokes with caps, then its probably a 390 horse car. If U bolts is a small block for sure. The problem with sway bars is that there are factory and aftermarket sway bars, and truthfully they aren't expensive to add. If the car is not original, or a bitsa...then its harder to discern configuration.
Pro
Joined: Jun 2007
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From: Stevens Point WI
Long shot but does that replacment motor you have use the original tach drive ditributor?
If so there is a tag wrapped around it that says what motor it was for
Thats what tipped me off on my car to keep searching untill more and more signs showed I had a 427/390 car
Also I think if it was a BB car the washer fluid was in a bag on the drivers side firewall instead of a jug, not certain on that one though
If so there is a tag wrapped around it that says what motor it was for
Thats what tipped me off on my car to keep searching untill more and more signs showed I had a 427/390 car
Also I think if it was a BB car the washer fluid was in a bag on the drivers side firewall instead of a jug, not certain on that one though