a very happy camper!!!

[Phil Genario]

the 73 arrived on schedule on friday, have it all on film, all went well,even the transporter liked it!he unloaded it at the lowes home store nearby.i am impressed ,the car is very nice. i spent the cold day today "sanitizing" it. 2 good coats of wax, dash detail,vents, knobs etc.it needs a few small things like new center caps, new lug nuts, exhaust tips need to be turned down.all very trivial.car runs and drives beautiful.the rear bumper has minor pepper haze on the top surface.all and all,very happy.so far the only remark i got about the color was from my mother, who said''its nice, but why did they paint it that color,youll never be happy with that" i did contact the original owner last night who was very nice and told me about its entire history, he bought it as a leftover in january, 1974!!he traded in a 70 monte carlo ss 454 on it.it listed for$6,354, he paid $5,000 for it.he also stated that the modified high performance engine option,codea3 was a stage one engine, i kinda doubt it,anyone know?thank god for documentation !thanks to all for all the positive feedback about this purchase,and the kind words about my my dog toby. greatly appreciated.

[centurion 455 ragtop]

Phil congrats on your new Centurion! Regarding the Stage 1 option. It would be designated in the 5th digit in the VIN. I am not sure and its getting late, (maybe someone can correct me if I'm wrong) but I think it has to be a "U" . With the Riviera Stage 1 it has to be a "W". The standard 455 in the Centurion it would be a "T".

With the big Buicks the camshafts are different from the standard big Buick camshaft and different from the GS Stage 1 camshaft.

Reasons the cam used for the GS Stage 1 is set for more hp than torque and a higher rpm. With the heavy big cars it was designed to produce the HP peak and torque at a lower rpm.

The Stage 1 option is also referred to as the HO Engine for the big Buicks. I have found it to be called both depending what book you are researching. They all have the larger valve heads, which are the Stage 1 heads, but the camshafts are different.

Camshaft Part #s for the Big Buicks

1973-1974 Riviera, Centurion with the 455 Stage 1 engine:
# 1384664 Exh lift: .457 at 340 duration, Intake lift: .410 at 297 duration

1972-1974 Riviera, Centurion non 455 Stage 1 engine:
# 1246739 Exh lift: .405 at 306 duration, Intake lift: .390 at 293 duration

Another '73 tid bit is the rear gears. The standard 455 rear was an open rear with 2.73 gears the only option was the 3.23 performance gears. If you had the standard 350 engine the gears offered were: standard 3.08, economy 2.73 and performance 3.42. The 455 Stage 1 optioned Centurions would also come with the 3.23 gears unless the buyer opted out for something different.

My sources are the:
Buick Engineering Features 1973
Buick Chassis Service Manual
ROA Articles by Dennis Manner

[Bob Alberini]

Phil and Rick,
I leave all the technical engine and axle stuff to you, Rick. That's way outside my realm.

But the engine code on the VINs (both for 72 and 73) has the T as the standard 455 with single exhaust, U as the standard 455 with dual exhausts and W as the high performance 455 with dual exhausts and your car is, of course, the W, Phil. The standard 455 carries the L74 UPC Code; your build sheet shows the L76 high performance version.

Sure glad that you are so pleased with the car overall and haven't found any real surprises. We'll all enjoy the photos when you get them on the site.

[centurion 455 ragtop]

Bob

Thanks for clearing that up with the VIN code. :xyxthumbs: I get them mixed up and after going thru the books I just gave up and took a questimate:rooleyes2: its late, I'm tired but I don't want to sleep:Dou:

[Bob Alberini]

Glad to help, Rick, and when you guys start on the technical end, I'm the deer in the headlights and have no idea what you're talking about! It's a good thing I have a good mechanic.

[Bob Alberini]

One more thing I forgot to mention early this morning, Phil. Considering your car was built in January 73 and according to the owner purchased as a left over in January 74, the dealer had that car a long time. One has to wonder if some felt as a Centurion it had too high a sticker price or the color was a detriment to some folks or a combination of the two? That was a long time for a car to sit in a dealer's inventory. It is terrific that you got to speak with the original owner and get some history and he's probably quite glad that his car has another great home.

[Phil Genario]

Phil congrats on your new Centurion! Regarding the Stage 1 option. It would be designated in the 5th digit in the VIN. I am not sure and its getting late, (maybe someone can correct me if I'm wrong) but I think it has to be a "U" . With the Riviera Stage 1 it has to be a "W". The standard 455 in the Centurion it would be a "T".

With the big Buicks the camshafts are different from the standard big Buick camshaft and different from the GS Stage 1 camshaft.

Reasons the cam used for the GS Stage 1 is set for more hp than torque and a higher rpm. With the heavy big cars it was designed to produce the HP peak and torque at a lower rpm.

The Stage 1 option is also referred to as the HO Engine for the big Buicks. I have found it to be called both depending what book you are researching. They all have the larger valve heads, which are the Stage 1 heads, but the camshafts are different.

Camshaft Part #s for the Big Buicks

1973-1974 Riviera, Centurion with the 455 Stage 1 engine:
# 1384664 Exh lift: .457 at 340 duration, Intake lift: .410 at 297 duration

1972-1974 Riviera, Centurion non 455 Stage 1 engine:
# 1246739 Exh lift: .405 at 306 duration, Intake lift: .390 at 293 duration

Another '73 tid bit is the rear gears. The standard 455 rear was an open rear with 2.73 gears the only option was the 3.23 performance gears. If you had the standard 350 engine the gears offered were: standard 3.08, economy 2.73 and performance 3.42. The 455 Stage 1 optioned Centurions would also come with the 3.23 gears unless the buyer opted out for something different.

My sources are the:
Buick Engineering Features 1973
Buick Chassis Service Manual
ROA Articles by Dennis Mannerthe letter on my vin is a w. the entire vin reads 4p57w3x145741

[Phil Genario]

One more thing I forgot to mention early this morning, Phil. Considering your car was built in January 73 and according to the owner purchased as a left over in January 74, the dealer had that car a long time. One has to wonder if some felt as a Centurion it had too high a sticker price or the color was a detriment to some folks or a combination of the two? That was a long time for a car to sit in a dealer's inventory. It is terrific that you got to speak with the original owner and get some history and he's probably quite glad that his car has another great home.yeah bob, who knows? that car was a dealer swap at some point as my window sticker says bill davidson buick, atlanta, and it was purchased at hanson buick in tucker.the original owner don mcclair told me this. he also said he wanted a new 74 riviera,but they gave him such a good deal on the centurion he took it. very good choice!!!he also said his parents had a new73 lesabre custom coupe, same color combo. yeah i wonder why it sat, id guess the color.the sticker also could have been an issue, my mothers 72 electra stickered under that!the only thing im still quesy about is the color.

[Phil Genario]

maybe one of you guys can figure this out as i sure as heck cant. on the window sticker of my 73(which ill scan and post ) there are a couple of things i dont understand. on option a3 modified high performance 455, it includes th400 trans,specific cooling and energizer,and dual exhaust. then2 options down it has code e1, again dual exhaust this time its a $30.00 option! why if its included in a3 is there a charge for it in e1? code w7 states bodyside accent stripes,yet there is no charge for it ,it wasnt standard im sure. than option code n2 bumper protective strips $24.00 i dont think i ever saw any 73 full size without them.i would have assumed they were standard as they were in 72. im almost sure of it. also strange that a car this loaded out and they didnt order carpet savers!

[centurion 455 ragtop]

the letter on my vin is a w. the entire vin reads 4p57w3x145741

You scored not only a nice one, but a rare one too!

4 - Buick
P - Centurion
57 - 2 door coupe hardtop
W - 455-4 Stage 1 dual exhaust block production code XA
3 - 1973
145741 - sequence

Like I mentioned before unless they changed the gears it should have a posi unit with 3.23 rear gears.

[Phil Genario]

nothing on the window sticker indicating posi, was this just included?ill have to look underneath and see if the tin tag is there.thanks for the info, maybe this will get me off the color issue!

[centurion 455 ragtop]

maybe one of you guys can figure this out as i sure as heck cant. on the window sticker of my 73(which ill scan and post ) there are a couple of things i dont understand. on option a3 modified high performance 455, it includes th400 trans,specific cooling and energizer,and dual exhaust. then2 options down it has code e1, again dual exhaust this time its a $30.00 option! why if its included in a3 is there a charge for it in e1? code w7 states bodyside accent stripes,yet there is no charge for it ,it wasnt standard im sure. than option code n2 bumper protective strips $24.00 i dont think i ever saw any 73 full size without them.i would have assumed they were standard as they were in 72. im almost sure of it. also strange that a car this loaded out and they didnt order carpet savers!

OK I'll give it a shot. The A3 option for the '73 is the modified HiPerformance 455. When you either ordered the HiPerf. 455 or the Standard 455 you also must have dual exhaust. So you had to buy that option too which is E1. Why it's not included in price? Well money is money and they get more out of ya:p That is my only guess.

As with the TH400 trans, I am pretty sure the standard 350 engine in the Centurion came with the standard 350 transmission. When you ordered the 455 it also came with the TH400 trans all included in the option price. There is an optional I3 which is the heavy duty egine and transmission cooling

The Bumper strips N2 option, you got me I would say the same, that I never saw a 73 without them. On the option sheet it states front and rear. Again maybe for the same reasons on paying for the dual exhausts they now charged you for the bumper strips. Looking at the Chassis Service Manual, page 2B-18 it illustrates the bumper and those strips that we know of are referred as Rubber Strips. So I guess it was an option that just about every 73 Centurion had.

The body accent stripes, no charge...got me, maybe it was a free-bee by the dealer.

[centurion 455 ragtop]

nothing on the window sticker indicating posi, was this just included?ill have to look underneath and see if the tin tag is there.thanks for the info, maybe this will get me off the color issue!

The TH400 Transmission.

Get under the car on the passenger side looking at the side of the trans. There should be a small two inch by one inch tag rivited onto the trans case. There will be 2 large letters on this tag which is the Transmission Code.

BC - Standard 455, LeSabre, Centurion, Electra, Estate Wagon & Riviera

BT - Hi Performance 455, Riviera GS, Centurion Electra, LeSabre

My guess is yours will read "BT" Unless the trans was replaced.


THE REAR END

You have to get under the car on the passenger side axel tube on top next to the center carrier there will be a code. You may need some break cleaner and rag and goggles and a good drop light to clean the area.

There will be a series of letters and numbers
EXAMPLE:
UM B 085 2

UM - designate 3.23 gears
B - designates Buick
085 - designates Day of year built (85th day of year)
2 - designates the work shift.

I am pretty sure that if it's a UM its a posi rear with 3.23 gears
If it is a VM then it is a non posi with 3.23 gears.

Another easy way: Jack up the car safely chock the front wheels and put it in neutral. Manually turn one back tire and look to see if the other side turns in the same direction at the same time. If so then you have a posi.

[Smartin]

The W code engine has nothing to do with the rear end selection. That is a completely different option, and has to be ordered specifically with a positraction rear if wanted.

[centurion 455 ragtop]

Adam

The only gear ratios offered for the 73 cars with the 455 option are the 2.73 and 3.23 ratios. I guess it would make sense that the 2.73 is the standard ratio. We would only hope when the car was ordered with the Hi Performance 455 they installed the 3.23s.

Is it correct then to say it should be in his Buildsheet? The option codes?

On the order sheet the Performance axle is G2 and it requires the option code A1 dual exhaust, and A9 the 455 engine. Posi traction code on that sheet is G4 and if the code is GA then it is both performance axel and posi traction.
It lists in the Buick Engineering Features the Performance axel being 3.23 gears.

The Buildsheet should tell it all I would figure

[Richard Dunn]

Bob wrote that this car was built in January of 1973 and then sold one year later in january 1974.
Maybe it was a demo or the dealer's personal car?
Anyway.....the car is a beauty!

Remember what happened in that magical year of 1974?
The gas embargo happened.:shocked:
Amazing someone purchased a high performance 455 V-8 when suddenly there was no gas to be had.
I remember sitting in gas lines for an hour or more at 4:00 in the morning in the burbs of Philly.
My 1971 Centurion burned gas like.....well like gas.

[Smartin]

Yes, the gear ratio and whether it was a posi or not will be stated on the buildsheet and/or the original wholesale car order.

[Centurion]

Phil, it was the case in 1971 that the Centurion paint stripe was a no-cost factory option. This surprised me also. I suspect that this was also the case for the 1972 paint stripe and the 1973 tape stripe.

[Phil Genario]

Bob wrote that this car was built in January of 1973 and then sold one year later in january 1974.
Maybe it was a demo or the dealer's personal car?
Anyway.....the car is a beauty!

Remember what happened in that magical year of 1974?
The gas embargo happened.:shocked:
Amazing someone purchased a high performance 455 V-8 when suddenly there was no gas to be had.
I remember sitting in gas lines for an hour or more at 4:00 in the morning in the burbs of Philly.
My 1971 Centurion burned gas like.....well like gas.nope, according to bob mcclair the original owner,the car was brand new, and simply was a leftover,he suspected it didnt sell due to the gas crisis,and why not before remains a mystery.so we can honestly say it probably was the last centurion sold new !!he also stated the under dash buick 8 track along with trumpet horn were dealer installed when new.