Jump to content

“A” and “B” R3/4 engine designation…why?


Nelson

Recommended Posts

I’ve always wondered the significance of the A and B designation for the R3 and R4 engines. I’ve been thinking about this for years . I’ve asked the Granatellis with no luck at all. It dawned on me that the A engines were probably built in 1962 and probably were basically 299 engines with reworked standard cylinder heads. The B engines I originally thought were 304 with R3/4 cylinder heads until i found some B engines with 299 ci with the late cylinder heads. Then I remember the six cylinder Bonneville engines were also given B numbers. So my deduction would be all engines built in 1962 were simply A engines and are very few in number. All 1963 engines were B engines and so happened to have the new cylinder heads on the V8 and the six was assigned a B number because of the year. Paxton’s paperwork for expenditures were A for 1962 and B for 1963. This sounds reasonable to me. What do you think?

Edited by Nelson
Link to comment
Share on other sites

  • Nelson changed the title to “A” and “B” R3/4 engine designation…why?

Some of the Pre-production PROTOTYPES had R3 engines. It's not a late thing. It was an engineering exercise all along. 

 

Link to comment
Share on other sites

I'd say Nelsons hypothesis makes sense, and, to my knowledge, hasn't been brought forward before this....

Interesting.......!

(The paper trail makes me wonder)

Edited by mfg
added text
Link to comment
Share on other sites

51 minutes ago, brad said:

Some of the Pre-production PROTOTYPES had R3 engines. It's not a late thing. It was an engineering exercise all along. 

 

i know you have had some of the preproduction prototypes in your shop. Do they have B numbers or EX numbers on the block? The B would probably be a Paxton designation and the EX a South Bend engineering designation. Another piece to the puzzle.

Link to comment
Share on other sites

They are EX numbered. I haven't opened it up yet.  do know the next serial number higher EX car did have an R3 (also EX numbered.

 

 

Link to comment
Share on other sites

13 minutes ago, Mrelmtow said:

Are any A engines stamped on the block like the B engines? According to paperwork I found in regards to my car 1025, mine was assigned an A number but there are no stampings on the block.

Yes, I remember your block has a normal 'RS' number....maybe Brad or Nelson can answer your question.

Link to comment
Share on other sites

1 hour ago, regnalbob said:

There were two A Engines listed on the R-3 Registry in 2012..

A-5, which was installed in R-3923 used by a Paxton manager.

Later it may have been installed in R-5013.

A-10, owned by Jon Myer.

RS-1021 used in R-1025 did not have a Paxton number.

 

Bob that's 63R1025 🙂

Link to comment
Share on other sites

1 hour ago, mfg said:

Bob that's 63R1025 🙂

I tried to provide some information that I thought would be of interest to forum members.

For some reason you think it is necessary to take issue with the serial number.

Before you criticise someone make sure you are correct.

Actually you are wrong.

The correct number is 63R-1025.

 

 

Link to comment
Share on other sites

4 hours ago, regnalbob said:

I tried to provide some information that I thought would be of interest to forum members.

For some reason you think it is necessary to take issue with the serial number.

Before you criticise someone make sure you are correct.

Actually you are wrong.

The correct number is 63R-1025.

 

 

Ahhh...the elusive hyphen!!! 🤔

Edited by mfg
Changed text
Link to comment
Share on other sites

20 hours ago, regnalbob said:

There were two A Engines listed on the R-3 Registry in 2012..

A-5, which was installed in R-3923 used by a Paxton manager.

Later it may have been installed in R-5013.

A-10, owned by Jon Myer.

RS-1021 used in R-1025 did not have a Paxton number.

 

According to my research it was assigned an A number.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...