Help me decode my '69 BB
Thread Starter
Instructor
Joined: Oct 2004
Posts: 205
Likes: 15
From: East Greenwich NJ
Help me decode my '69 BB
I've consulted my Corvette By the Numbers and don't have the answer.
My engine block code tells me the motor was a 427/400 motor. It is not the original motor for my car. It has the tri-power set up and high performance heads from a '67, which I understand to be compatible (please correct me if I am wrong there). So, I am running 427/435 badging, but not telling anyone this is a number matching machine, although it is set up like it would have been had GM assembled this from its parts bin at the time ('69 block).
Here's my issue -- the tach has a 5600 redline, which seems low. Can anyone tell me what Vette came with that tach? I realize the tach theoretically could have been replaced, but that may be a clue to which BB came with the car. Oh, and it's a side pipe car and VERY late production -- 35909 of 38762.
Any help would be appreciated.
My engine block code tells me the motor was a 427/400 motor. It is not the original motor for my car. It has the tri-power set up and high performance heads from a '67, which I understand to be compatible (please correct me if I am wrong there). So, I am running 427/435 badging, but not telling anyone this is a number matching machine, although it is set up like it would have been had GM assembled this from its parts bin at the time ('69 block).
Here's my issue -- the tach has a 5600 redline, which seems low. Can anyone tell me what Vette came with that tach? I realize the tach theoretically could have been replaced, but that may be a clue to which BB came with the car. Oh, and it's a side pipe car and VERY late production -- 35909 of 38762.
Any help would be appreciated.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Thread Starter
Instructor
Joined: Oct 2004
Posts: 205
Likes: 15
From: East Greenwich NJ
"Phony" is a bit harsh. It is only phony if I try to pass it off as an original, numbers matching car, which I certainly do not. Hydraulic cam -- yes -- but custom grind with a full rebuild. I run pump gas and will keep up with the solid lifter crowd without the need to run to the race shop every time I need to burn obscene quantities of fuel. I am in this to drive my car, but am interested in history as well. My "true" red line is more like 6500, although I try to stay below!!!
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Sorry to offend you. I dont care what badging you have but I thought you wanted some straight talk about what it actually is. Hell go all the way and put a L88 hood on it too. However if you ever run across a real '435' you had better tape your doors shut because a real one will blow them off........ 
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
Sorry to offend you. I dont care what badging you have but I thought you wanted some straight talk about what it actually is. Hell go all the way and put a L88 hood on it too. However if you ever run across a real '435' you had better tape your doors shut because a real one will blow them off........
and the 435hp badging isn`t trying to "pass it off"? maybe what you have is a 435hp aircleaner sticker.....
Team Owner
Joined: Jun 2000
Posts: 38,923
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From: Southbound
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Drifting
Joined: Sep 2006
Posts: 1,259
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From: MS
Pull the codes off the tranny and rear axle. The L71 manual came only with the M21 and had the 3.55's stock with 3.36, 3.70 and 4.11 optional. The L36/L68 came standard with the M20 and 3.08 with the 3.36 optional or you could order the M21 with 3.36, 3.08, 3.55 or 3.70. So finding a matching numbers M20 in the car would mean L36/L68 and finding a 4.11 stamped axle would mean good chance it was an L71. Finding a 3.08 coded rear in the car would lean back to L36/L68 although no way of knowing if the rear in the car now is original. The car does have only one steel fuel line with no return line right?