[Baron Von Zeppelin]

We have a new member named GangGreen who owns a 73 Formula that was formerly his brothers car, his brother has passed on and now he has the car.

It is a Y-code VIN car with Automatic.

He has reason to believe it has an SD engine in the car.
So going to help him determine what it is.

Said to be a lifelong California Car.
I'm guessing maybe its a Brewster Green car ? From his screen name.

Here are some details :
"it’s in great original condition, saddle interior, automatic, air, auto windows, console, clock"

[Baron Von Zeppelin]

In first picture , notice how the PCV valve is routed into the oil filler cap on the driver side valve cover.
= SD only

In second picture , notice the cast characters "LS2" to the right of thermostat area = SD only
LS2 is the designation for SD455 engine ,,,, like Chevy had LS6 as a designation.
Also right next to thermostat area is a date code - for example K122 or E123 etc....

Third picture is where to find carburetor ID on driver side of carb.
This example is 17057274

[Baron Von Zeppelin]

If you don't have the special pcv arrangement and LS2 intake , probably not going to be an SD , unless its been modified , which can happen.

These further steps will document what you do have no matter what engine it is.
You will have defacto confirmation.

Picture one is the head code ID , #48 in this example.

Picture two is the head date code , H208 in this example.

It should only take a couple minutes to verify your carb , intake , and heads.
After that report from you , i will go into all the ID's on the block.
It is also easy stuff to find and capture.

[johnta1]

A thread on SD 455 that is being restored:

SD 455


The head is round port.

Looks like this:



There is a 1 and a 6 on middle ports.

The distributor will be different compared to normal distributors.
The hole it goes into is a lot bigger. Probably can't tell installed though. It has a code on it that will tell.

The below the back of the passenger head on the block is a casting number that will ID the SD block also.

Pictures will help tremendously.

Sounds like an awesome car, though.

[Ganggreen]

Some pictures

[Ganggreen]

More pictures

[Ganggreen]

More pictures

[Held for Ransom]

Navajo Orange. VIN indicates 455, non-SD. Heads looks like a 71 400.

[Baron Von Zeppelin]

71 72 73 year model 455 block - Code YC
With the partial 0 character leading the EUN. " ( "
So it might be the original block , but it is not an SD block.
We can help you determine if it is the original block.

71 400cid heads #96
That's a popular 455 build combo with those heads to bump compression ratio.

Intake is a 1972 model.

Appraiser didn't know his azz from a hole in the ground.
But you have a Very Nice Formula 455 in a great color combo.

The rivets on trim tag are not factory rivets .
By that time in 73 production they were actually using the bolt head screws instead of rivets.

The steering wheel collar looks like a corrugated drain hose was utilized as a sleeve.

[johnta1]

Definitely not a SD block. Need the partial VIN on block to see what year it is. Hopefully at least a 455.

Cowl tag has rivets that look aftermarket. (should be screws anyway)

I'd say don't trust the appraisal?

Car looks good, some mods to it.

[johnta1]

Treed by BVZ!

[Baron Von Zeppelin]

The EUN on the block is extremely too low to be original .
That is a low count EUN from the beginning of whatever production year.

( 003286 is ultra early in a model year , but your car is ultra late built in 73 model year.

[Baron Von Zeppelin]

73 Fbody production didn't start until Sept or Oct of 1972 because of the 72 strike at Norwood..
73 Fbody production ended in July or August of 1973.
So your Formula was nearing the end of the model year with an 07B body date
= 2nd week of July 1973

W66 on the trim tag is the indicator for Formula Firebird.

[Baron Von Zeppelin]

The dashpad , metal dash , console would not be black with a saddle interior.
They would all be saddle tones.
The carpet should be much darker also.

Just little factoids to bring you up to higher knowledge.

I owned a 73 SD TA for 20 years with an untouched saddle interior.

[Baron Von Zeppelin]

The invoice from PHS will tell you things like -
If the car was originally built with the RamAir Induction option that is on it now.
That was a fairly rare option.

It was possible to order Orange carpet in 1973 , maybe it had that originally and he changed it.
If the Formula wheel was original it will tell.
And will tell which dealership sold the car new.

[Baron Von Zeppelin]

Here is an Invoice for a Navajo Orange 73 Formula 400 that was ordered with RamAir and Orange carpet.

[Baron Von Zeppelin]

Here are some block ID pics.

Pic one is the date code - at the back near distributor .
Usually can jam a cellphone camera in there with flash on and capture it.
I038 on this example.

Pic two is the block casting number - at rear of block on passenger side.

Pic three is the partial VIN - down low on front face , passenger side.

Since the car was out in Cali , the replacement block may be from a Cali built car.
Fremont cars will have the VIN in a different spot - up higher towards the top - on the same flat face - on passenger side.

455's have actual 455 in raised numerals cast on one or both sides - around freeze plug vicinities.

[Baron Von Zeppelin]

The #96 heads increased the comp ratio to around 9.5 : 1
The stock #4X heads would have been about 8 : 1

The 1973 intake would have had an EGR valve
Probably why he switched to a 72 intake.

He may have bought that engine already built by someone in the specialty Pontiac sector , and turned in the original engine to save the core charge.

[Held for Ransom]

If you post a picture of the underside of the ram air air cleaner, I might be able to tell the year.

[Ganggreen]

More pictures