'74 454 ??? Need expert opinions

[Pamela H.]

Hi all,

Can anyone out there in Corvette Land tell me how many 454 Convertibles were built in '74??? Have asked this question to people that I thought would know but have been told that these records are not available. I find that very difficult to believe.

Shoulder belts??? Would these cars have been equiped with shoulder belts from the factory? Mine shows no evidence of this and prior owner actually had them installed....I had them removed.

Third question can any of you tell me what contitutes a Heavy duty suspension on this car and how do I know if I have one??? I know the number of leaf springs is involved but ....were all 454's heavy duty???

Does the heater core on this car with air ever go in via the fire wall side or always thru the dash?

Convertible top installation...Can anyone give me guestimate on number of hours to install so I don't get taken when having the new top installed.

I've looked thru countless Corvette magazines and seen NCRS license plates, but when I went to the "store" to order them they don't have them. Where can I find them?

No laughing allowed!
Thanks so much!!!
Pam

[Joe L.]

Re: '74 454 ??? Need expert opinions

Hi all,

Can anyone out there in Corvette Land tell me how many 454 Convertibles were built in '74??? Have asked this question to people that I thought would know but have been told that these records are not available. I find that very difficult to believe.

Shoulder belts??? Would these cars have been equiped with shoulder belts from the factory? Mine shows no evidence of this and prior owner actually had them installed....I had them removed.

Third question can any of you tell me what contitutes a Heavy duty suspension on this car and how do I know if I have one??? I know the number of leaf springs is involved but ....were all 454's heavy duty???

Does the heater core on this car with air ever go in via the fire wall side or always thru the dash?

Convertible top installation...Can anyone give me guestimate on number of hours to install so I don't get taken when having the new top installed.

I've looked thru countless Corvette magazines and seen NCRS license plates, but when I went to the "store" to order them they don't have them. Where can I find them?

No laughing allowed!
Thanks so much!!!
Pam

Pam-----

There's no way to know exactly how many LS-4 convertibles were built for 1974. Chevrolet kept no records relative to combinations of options. We know that 3,494 cars were equipped with LS-4. We also know that 14.6% of all 1974 Corvettes were convertibles. So, we could estimate that approximately 510 1974 Corvette convertibles were equipped with LS-4.

Shoulder belts were standard on coupes but optional on convertibles. 618 1974 Corvette convertibles were equipped with the optional shoulder belts. Apparently, your car was not one of them.

Corvettes with HD suspension (FE-7 for 1974) will have 7 leaf rear springs and will have a a 15/16" front stabilizer bar. It will also have specific shocks but these have likely been changed by now. 454's were not automatically equipped with HD suspension.

Heater core installation is accomplished from the dash side. I have heard of a few folks that claim to have done it from the firewall side. I would not even attempt such a replacement from the firewall side.

[Paul B.]

Re: '74 454 ??? Need expert opinions

Heater core installation is accomplished from the dash side. I have heard of a few folks that claim to have done it from the firewall side. I would not even attempt such a replacement from the firewall side.

Due to the size of the 454 engine, I do not think the evap housing on the engine side can be removed with the engine in the car. I did it once on a C3 smallblock car and it was darn near impossible.

[Jim T.]

Re: '74 454 ??? Need expert opinions

Pam for your convertible top replacement you could schedule an appointment with Al Knoch Interiors when they visit a Corvette function location near you and get a professional installation by the maker of very good Corvette convertible tops. Check their web page for dates and locations.

[Pamela H.]

Re: '74 454 ??? Need expert opinions

Is there no where, anywhere a list of VIN numbers of the LS -4 '74 production run? I believe that the Vin list would give me the answers I'm looking for.

Vette Magazine says that Chevy turned over the VIN data cards to the museum but the museum says they don't have them????

Thanks for the replies.

[Joe L.]

Re: '74 454 ??? Need expert opinions

Is there no where, anywhere a list of VIN numbers of the LS -4 '74 production run? I believe that the Vin list would give me the answers I'm looking for.

Vette Magazine says that Chevy turned over the VIN data cards to the museum but the museum says they don't have them????

Thanks for the replies.

Pam-----


There is no such list extant for 1974 (or earlier and some later) Corvettes. Folks have been looking for just such information for years. It's never been found and I don't think it will ever be found. Chevrolet did turn over certain production information to the museum but it does not go as far back as 1974.

By the way, if the sort of information you seek is ever found, you'll find out about its existence so fast it will make your head swim. It will be an "earth shattering" event that will be on the front page of every Corvette magazine and the instant topic of discussion on every Corvette discussion board that exists.

[Stuart C.]

Re: '74 454 ??? Need expert opinions

gee, I was wanting to know same production info......

[Robert S.]

Re: '74 454 ??? Need expert opinions

I have a 74' convertible with air (but with a small block) and have done the heater core remove and replace. It is definitely intended to be done from the passenger compartment side. It is not a difficult task but is very time consuming if one has never done it before - I would guess it took me a good 8 manhours of work to get the old one out and about the same amount of time going back together. The worst part of the task was to get to the brace bolt and nut which is bolted to a cast bracket way up behind the dash in the vicinity of the steering column. There is some valuable info on this task on the internet if you do some searching.
I cannot comment on your other questions.

[Pamela H.]

Re: '74 454 ??? Need expert opinions

Thanks for the feedback! anywhay the heater core is nothing I would ever tackle myself. Have watched one being replaced on a car without air and the video (U TUBE) looked pretty straight forward (from the engine side) and it only took about 30 min! But have been told that it can't be done that way on one with air. What scares me is when you say it took you 8 hours to get it out and another 8 to get it back in, I choke at the cost of labor on a job like that. I'm traveling and have no where to work on that kink of a project so will have to pay someone to replace it. I think I will wait until the old one really dies! I already have the part but I think I'm gonna have to start a special savings account to actually have it installed! :^)

[Pamela H.]

Re: '74 454 ??? Need expert opinions

Thanks for the info on the suspension...that will help.

I also really like your numbers as for your guestimate of the number of '74 convertibles with the LS-4. Now my next question is what woyld you consider a conservative annual percentage estimate for lost/stolen/destroyed? We've done the numbers with one figure but would like an idea of what percentage you might use to calculate the number. Once i hear your thoughts I'll post my numbers and you can shoot holes in it or maybe agree....anxiously awaiting your reply

[Joe L.]

Re: '74 454 ??? Need expert opinions

Thanks for the info on the suspension...that will help.

I also really like your numbers as for your guestimate of the number of '74 convertibles with the LS-4. Now my next question is what woyld you consider a conservative annual percentage estimate for lost/stolen/destroyed? We've done the numbers with one figure but would like an idea of what percentage you might use to calculate the number. Once i hear your thoughts I'll post my numbers and you can shoot holes in it or maybe agree....anxiously awaiting your reply

Pam------


I'd say 40-50% of the cars are gone, never to be resurrected.

[Pamela H.]

Re: '74 454 ??? Need expert opinions

Well Stuart, I guess we are both out of luck on this one!

Does your car have air? How about the maplight? Could you tell me how you determined where the car was originally sold?
What color is yours? Mine is yellow...not for long but is still the original color. Needs to be stripped, but im not ready for the $10,000 paint job yet so will have some fun with it first...

[Pamela H.]

Re: '74 454 ??? Need expert opinions

Well I found it...Let me know what you think, We posed this to my daughter who has a degree in theoretical math,...will post her response next.

rare. It has low production numbers and a unique configuration of options. I have tried to do the math in every possible permutation and the answers I get are exciting BUT maybe I am missing something. I need a tutor.
Here are the known facts:
1. In 1974 Chevy produced a total of 37,502 Corvettes (across all body styles, all motors and all options.
2. 5,474 were convertibles
3. 2,612 had the factory ordered hard top option.

Okay, now hang with me, going back to the original production figure of 37,502 78. 4% of all the Corvettes had air-conditioning (29,397)
After that, about 67% of the whole group had an automatic transmission. 25,146
Now, here is the frosting. 3,494 cars were built with the 454 motor option. 9.3% of the total production. Here is what my math looks like
Convertibles = 5,474 Hard Tops = 2,612
Air Conditioned convertibles w/hard tops = 2,047 (78.4%)
Air Conditioned convertibles w/hard tops and automatic 1,372 (67%)
Air Conditioned convertibles w/hard tops and 454 128 (9.3%)

128



127.5 cars.

What am I missing? Is it possible that only 128 cars rolled off the production line in St. Louis optioned exactly like that?
There are other variables-
Power windows, tilt wheel, power steering, BUT?????? 128 cars?????
Katie, is my math correct? Am I not seeing the whole picture? HELP ME PLEASE!


END



In the second decade 0.5% per year, stolen or destroyed. (They started to garage them, took better care, drove them less often)

are still all original.

[Joe L.]

Re: '74 454 ??? Need expert opinions

Well I found it...Let me know what you think, We posed this to my daughter who has a degree in theoretical math,...will post her response next.

I have found (and purchased) a ’74 Corvette that I believe is rare. It has low production numbers and a unique configuration of options. I have tried to do the math in every possible permutation and the answers I get are exciting BUT maybe I am missing something. I need a tutor.
Here are the known facts:
1. In 1974 Chevy produced a total of 37,502 Corvettes (across all body styles, all motors and all options.
2. 5,474 were convertibles
3. 2,612 had the factory ordered hard top option.
That’s the basis –
Okay, now hang with me, going back to the original production figure of 37,502 78. 4% of all the Corvettes had air-conditioning (29,397) I figure less people would get air in a convertible, but for the purposes of this problem – I am going to assume an equal distribution across the whole sample
After that, about 67% of the whole group had an automatic transmission. 25,146 –again, I am assuming an equal distribution between the coupes and the convertibles.
Now, here is the frosting. 3,494 cars were built with the 454 motor option. 9.3% of the total production. Here is what my math looks like
Convertibles = 5,474 Hard Tops = 2,612
Air Conditioned convertibles w/hard tops = 2,047 (78.4%)
Air Conditioned convertibles w/hard tops and automatic 1,372 (67%)
Air Conditioned convertibles w/hard tops and 454 128 (9.3%)

I’m working on the theory that there were a total of just 128 cars built – optioned exactly like I’ve described.

The numbers of convertibles can’t change.
The numbers of hard tops can’t change.
The other numbers are flexible depending on the order in which you do the steps – but the final result in each of six different efforts all come to the same result 127.5 cars.

What am I missing? Is it possible that only 128 cars rolled off the production line in St. Louis optioned exactly like that?
There are other variables-
Power windows, tilt wheel, power steering, BUT?????? 128 cars?????
Katie, is my math correct? Am I not seeing the whole picture? HELP ME PLEASE!

The kicker – there were 10 color options in 1974. So whatever the final number is, only one tenth of them would be yellow or any given color and some colors ie white, red, blue, silver would have been the more popular colors leaving the other colors ie yellow much lower.
END
This isn’t really part of the puzzle (yet) but it is a significant factor in trying to value the car.
Of all the corvettes made in 1974 – I figure 1% of them got stolen or wrecked every year for the first ten years. (That number is probably higher but I have no facts to support my theory)

In the second decade 0.5% per year, stolen or destroyed. (They started to garage them, took better care, drove them less often)
In the third decade 0.25% lost per year. And in the last seven years – I’m using 0.125% per year.
So imagine how many of these cars are still “out there” and how many are still all original.

Pam------


All you found are someone's ESTIMATES which use the same, basic rationale that I used earlier.

[Patrick H.]

Re: '74 454 ??? Need expert opinions

rare. It has low production numbers and a unique configuration of options.
are still all original.

Pamela,

In car land, color and body is often not considered when calculating rarity. Engine option and year tend to be the top if not only items considered.
As has been said here before, if you play with option numbers enough, as you've just done, almost any car in the first half of Corvette's history could be come "rare."
However, when there are cars that are one of 2 or one of 10 to ever receive an engine option, much less body shape, color and other options, yours ends up being one of a couple thousand 454 1974 convertible Corvettes in the comparison.
That's just how the numbers in this hobby tend to roll.

Patrick