C3 General General C3 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by:

Help needed concerning 1970 engine suffix CTO.

Thread Tools
 
Search this Thread
 
Old Oct 23, 2012 | 01:09 PM
  #1  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default Help needed concerning 1970 engine suffix CTO.

The black book says 350, 350 hp manual trans, and ac. However the ncrs 70-72 tech manual says Flint reports none were produced. Their existence is unverified. My buddy's 70 has this non existing motor in it with a correct vin. To the best of my knowledge it is not a re-stamp.

Is this a super rare code? Thanks in advance.
Reply
Old Oct 23, 2012 | 01:43 PM
  #2  
Sargevette's Avatar
Sargevette
Burning Brakes
 
Joined: Dec 2005
Posts: 819
Likes: 3
From: Flowery Branch Ga
Default

Found some info on google. No production numbers but it's a real code.

Code Year CID Vehicle HP RPO Trans Carb Comments
CTO 70 350 Corvette 350 L-46 4-spd 4-Brl A/C
Reply
Old Oct 23, 2012 | 02:08 PM
  #3  
Easy Mike's Avatar
Easy Mike
Team Owner
Supporting Lifetime
20 Year Member
 
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Default

Please post both numbers on your friend's engine pad. Tell us more about his car.

Reply
Old Oct 23, 2012 | 02:24 PM
  #4  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Engine pad reads: 70 S416088 V0429CTO


Car is a 70 coupe, 4 speed, air car. Will try and get a pic tmrw.
Reply
Old Oct 23, 2012 | 02:33 PM
  #5  
Easy Mike's Avatar
Easy Mike
Team Owner
Supporting Lifetime
20 Year Member
 
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Default

Originally Posted by John 65
Engine pad reads: 70 S416088 V0429CTO...
#16088 was assembled in July, 1970, final month of production. An engine assembled on April 29th is a bit of a stretch for a car assembled three months later, but stranger things have happened.

Reply
Old Oct 23, 2012 | 03:06 PM
  #6  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Thank you sir !



Trim tag is G21 July 21st
Trans is June 16th, Rearend June also.

But still curious as to why no verified CTO stampings ?

Last edited by John 65; Oct 23, 2012 at 03:14 PM.
Reply
Old Oct 23, 2012 | 03:41 PM
  #7  
Alan 71's Avatar
Alan 71
Team Owner
15 Year Member
Active Streak: 120 Days
Community Influencer
Top Answer: 5
 
Joined: Sep 2006
Posts: 31,235
Likes: 4,326
From: Westminster Maryland
Default

Hi John,
Perhaps you may want to pm member Rowdy Rat with your info.
He may be able to offer some clarification since I believe he's looked at a few 70-72 cars over the years.
Regards,
Alan
Reply
Old Oct 23, 2012 | 03:50 PM
  #8  
Mike Ward's Avatar
Mike Ward
Race Director
10 Year Member
 
Joined: Jul 2001
Posts: 15,892
Likes: 42
Default

I read through my NCRS pocketbook- it makes no mention of the CTO code being rare or unusual, and specifically that it was replaced by code CTJ which was introduced at some time in the production year.

This infers that some cars should and would have had CTO.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-1

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-2

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-3

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-4

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-5

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-6

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-7

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-8

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-9

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
Old Oct 23, 2012 | 05:39 PM
  #9  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Thanks Alan I will.

Mike, the NCRS exact text is:

Flint reports none were produced. Their existence is unverified.

Just saying what it says.
Reply
Old Oct 23, 2012 | 06:16 PM
  #10  
Hammerhead Fred's Avatar
Hammerhead Fred
Melting Slicks
Active Streak: 30 Days
Liked
Loved
Community Favorite
 
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Default

Does it have transistorized ignition? Perhaps that's a CTQ
Reply
Old Oct 23, 2012 | 06:29 PM
  #11  
Hammerhead Fred's Avatar
Hammerhead Fred
Melting Slicks
Active Streak: 30 Days
Liked
Loved
Community Favorite
 
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Default

Originally Posted by John 65
The black book says 350, 350 hp manual trans, and ac. However the ncrs 70-72 tech manual says Flint reports none were produced. Their existence is unverified. My buddy's 70 has this non existing motor in it with a correct vin. To the best of my knowledge it is not a re-stamp.

Is this a super rare code? Thanks in advance.
I have this same documentation but cannot locate the reference for CTO that you cite. There is such a reference for CTR however. What edition, page, & section of the NCRS tech judging manual are you finding this information? Or are you referring to some other manual....
Reply
Old Oct 23, 2012 | 06:51 PM
  #12  
Hammerhead Fred's Avatar
Hammerhead Fred
Melting Slicks
Active Streak: 30 Days
Liked
Loved
Community Favorite
 
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Default

...you ran this up the flagpole once before.

http://forums.corvetteforum.com/c3-g...post1579538278
Reply
Old Oct 23, 2012 | 06:56 PM
  #13  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Originally Posted by Hammerhead Fred
Does it have transistorized ignition? Perhaps that's a CTQ
Thats what we thought but its deff an O.

Read this in the 4th edition of the ncrs 70-72 judging manual, page 54.
Reply
Old Oct 23, 2012 | 07:01 PM
  #14  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Originally Posted by Hammerhead Fred
...you ran this up the flagpole once before.

http://forums.corvetteforum.com/c3-g...post1579538278
Thats right, and obviously they are out there, but still the question remains..... why does the manual say they werent produced.
Reply
Old Oct 23, 2012 | 07:07 PM
  #15  
jr9170's Avatar
jr9170
Race Director
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Feb 2003
Posts: 13,238
Likes: 1,092
From: YANKEES UNIVERSE 70 454-LS5 500 ft-lbs Torque
Default

Any pics of the pad and the car that you can post ?
Reply
Old Oct 23, 2012 | 07:11 PM
  #16  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Will try and have a pic tommorow. A good friends car, if nothing else we are just curious.
Reply
Old Oct 23, 2012 | 07:40 PM
  #17  
jr9170's Avatar
jr9170
Race Director
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Feb 2003
Posts: 13,238
Likes: 1,092
From: YANKEES UNIVERSE 70 454-LS5 500 ft-lbs Torque
Default

Reply

Get notified of new replies

To Help needed concerning 1970 engine suffix CTO.

Old Oct 23, 2012 | 08:03 PM
  #18  
Hammerhead Fred's Avatar
Hammerhead Fred
Melting Slicks
Active Streak: 30 Days
Liked
Loved
Community Favorite
 
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Default

Originally Posted by John 65
Thats right, and obviously they are out there, but still the question remains..... why does the manual say they werent produced.
Because the previous edition of that same manual only references the CTR code. The CTL, CTM, CTN, and CTO codes were added to the 4th edition. That manual is compiled by the NCRS - not GM. The codes added to the 4th edition are all the "early" broadcast codes published by Chevrolet but later "replaced" by late production codes. This doesn't mean those codes were never used.

So, publish a photo and let's all have a look.
Reply
Old Oct 23, 2012 | 09:36 PM
  #19  
John 65's Avatar
John 65
Thread Starter
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Default

Thanks, will do.

Car will be getting a body off in the future. Want to make sure its correct.
Reply
Old Oct 24, 2012 | 01:51 AM
  #20  
Brcmpbl's Avatar
Brcmpbl
Drifting
 
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Default

Always curious about the 70 cars, seem to be able to throw curve *****. Mine is a CTJ car, L-46 with manual and AC, serial 400523 built approximately January 10, 1970 I believe.

Maybe I'm off base, but my understanding was that the V in the engine number indicated 1969 production. My engine is to the very best of my knowledge matching, and it is a V serial.

Last edited by Brcmpbl; Oct 24, 2012 at 01:58 AM.
Reply



All times are GMT -4. The time now is 01:44 PM.

story-0
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-1
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-2
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-3
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-4
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-5
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-6
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-7
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-8
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-9
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE