2.7 carrera engine numbers
 

Dear All,
let me introduce to you: I'm an Italian owner of 2.7 Carrera 1974 and ask your help.
During engine reparation I've taken some pics of engine numbers here attached. Now I've the doubt the numbers were redone in a later time and the engine block is not genuine 911/83.

An non original 911/83 block makes lose the car value? Do you suggest me to find out a genuine 911/83 block?http://forums.pelicanparts.com/uploa...1308917389.jpg
http://forums.pelicanparts.com/uploa...1308917505.jpg
http://forums.pelicanparts.com/uploa...1308917562.jpg


Thanks you very much for the attention you will pay.
regards
mattia

Mattia,

The core value of those cars lies with that special 911/83 engine so if yours has something else, I'd recommend sourcing the correct motor for the car.

Looks real to my amateur eye. What makes you doubt it?

It looks real but the doubt I have is on the numbers punched on the block, particularly the 911/83(maybe used a magnesium block from standart 2.7 150CV). Someone can give me his opinion? the genuine numbers characters seems to be different.....
The other engine parts (MFI, heads, cylinder...) are from carrera.

thanks again for your kind support

Mattia,
At first look the stamped numbers seem to look different than the factory type set. I would question the 9 and 3 for the 911/83 stamp.

Mattia

Looks funny to me

Here are some original factory stampings for comparison

http://forums.pelicanparts.com/uploa...1309166485.jpg

http://forums.pelicanparts.com/uploa...1309166585.jpg

http://forums.pelicanparts.com/uploa...1309166722.jpg

tom,
looks "funny"...with displeasure... also for me: I cannot understand what's done in the engine!
6640308 numbers looks real, but 911/83 is a fake for sure!

Opinion of a friend of mine is in the past original 911/83 was replaced with another 7R magnesium block (maybe 911/93 or /92 from non carrera 2.7) and made new self-made stamping.
Are 911/93 911/92 block exactly same of 911/83?
Finding original 911/83 is feasible? it worth? and parts into actual engine (crankshaft, rods...) can be re-used in the new block?
thanks and regards

The S/N also does not match anything in my cross reference list

A 73 RS motor should have a S/N starting with 663.

Tom,
car is european MFI 2.7 carrera from 1974 and S/N starts with 664...
it's not a 73 RS!
mattia

A '74 Euro Carrera should have an engine serial number starting with 665.

Normally the third digit states the year of the engine. Is the 74 Carrera different? I would think the s/n 664XXXX is a 74 build year.

It could be that my engine spec sheet has an error.

The type number has definately been messed with , whether an original mistake then rectified/restamped right after the original (mistake ?) was done...no one can ever say. But then combine it with the serial # stamping. Then the chances get compounded HARD towards the negative.

The serial number... funny 2nd 6 , the numeral 4 is definately not the normal one used. And besides there being no 2nd star (I have seen them go all the way into the corner partially on the vertical to get it in) , there seems to be something under the 8 (strangely , looks like possibly a star to me).

If you look at this in person with a magnifying glass you might be able to tell more.

Dear All,
something is going to be clear: the engine block maybe belong to a 2.4S re-bored to 90mm with original engine number 911/53. Someone may suggest how understanding the machined work for re-boring?
Look at the three pics: 911/83 (my fake), 911/83 (original), 911/53 (original) you may understand there are different fonts. My engine number is a mix of them!

Ciao
http://forums.pelicanparts.com/uploa...1309510241.jpg
http://forums.pelicanparts.com/uploa...1309510266.jpg
http://forums.pelicanparts.com/uploa...1309510285.jpg

mattia ,

Stampings interest me , so I have been looking at your thread to see if I can tell you anything I might notice (of which yesterday , I was looking at your unit number stamp again and it perplexes me. But we can get into that later.

First off , you (I/anyone viewing) need to know what we are comparing specifically (apple to apples ..etc.) .

What MY (model year) case is the third photo (the 911/83 stamp with the round head 3) .... 73 , 74 , 75 , or 76 ?? I could be completely wrong , but isn't the normal small 3 digit stamp tool font for 1973 MY type stamp a flat top 3 ? Similar to the motor unit number stamp flat top 3 ...only small. Is this correct / anyone ? I will ask someone I know to post a 73.


I do not know which small 3 was used in 74 , 75 , 76 MY . If anyone has any photos of any of these , maybe they could post

And what MY case is the 2nd photo (the clean stamped 911/53).... 72 , or 73 ??

As far as your number being changed from a 911/53 to a 911/83. If that was the case...why would the 3 be restamped...as it would already be there ?

Lastly take a close/clear photo of the casting date mark and post it. It might tell us something. This is it , circled in the photo :


http://forums.pelicanparts.com/uploa...1309573107.jpg

Mattia,

The correct 911/83 stamping should be like the last photo you show in your previous post. The 3 is rounded like that photo shows. I have photos from several '73 Carreras that show this style.

Unfortunately I have to agree with Ratbox. The serial number on your case was not done by the factory originally but has been restamped. The numbers are incorrect in style.

FYI the last photo shows a very rare Aluminum 7R 911/83 RS case.:)

http://forums.pelicanparts.com/uploa...1309636813.jpg

http://forums.pelicanparts.com/uploa...1309636873.jpg

http://forums.pelicanparts.com/uploa...1309636904.jpg

http://forums.pelicanparts.com/uploa...1309637037.jpg

Actually the '911' in Mattia's case is correct, but the '83' has been restamped sorry to say.

Thx Fryardds.


To the gallery , I have not studied small engine font per year as closely as the larger engine font for unit numbers.

Is this small font on the 911/53 case mattia provided a photo of , the norm for 1972 then ?


http://forums.pelicanparts.com/uploa...1309648514.jpg

Ratbox
agreed that numers had been restamped :( to end the issue, find a pics taken of casting date mark as for your suggestion.
It's only visible numer 50 and any idea about the meaning.
regards
mattia
http://forums.pelicanparts.com/uploa...1309773983.jpg
http://forums.pelicanparts.com/uploa...1309774113.jpg

mattia , thank you.

I'm still learning about magnesium case casting dates . If i'm not mistaken, I see a digit 3 where I have pointed . So that would make it a case cast in the 50th week of 1973 :

http://forums.pelicanparts.com/uploa...1309798480.jpg


Can anyone verify that single digit of the last year of the decade cast were at the right of the bar depression in this casting date on a 1973 / 74 vintage case ? And that in the example provided by mattia above is not just some slag that strangely looks just like a numeral 3 ?? (I would find this hard to believe but one never knows). More from this vintage would need to be examined.

I know by 1977 , this casting date layout had changed . And the last 2 digits of the decade it were cast was below the bar. And I cannot tell for certain , without having one of each physically in front of me. But on mattia's example the circle seems like raised material with the bar and numerals being depressions within the raised circle. In the example below , it seems (to me) to be the opposite.....that the circle is a depression & that the numerals & bar are raised material within the depression.

Here is an example from 1979.


http://forums.pelicanparts.com/uploa...1309799794.jpg


Thx again mattia. Now back to your case. I would not be so quick to discount your case as being anything one way or another until you study it harder. Way too many people are quick to discount things as 'phony' just because they are differant than the norm. One does not always mean the other.

I do not know anything for certain . But a few questions go off in my mind. First , why would someone do the unit number so strangely if they were trying to fool anyone ? And if stamped over a complete other existing unit number , why does the surface not look like it has been ground ?

Lastly I have seen all the digit stamps on your unit number (664 0308) used by the factory before. Even if I said the were not the 'normal' ones used for that location / that year. I did not mean they were fonts that were never used

Again, I would break out some high powered magnifying instrument , and examine things very closely. Is that actually a star under the 8 ? Is it an 8 and not a 3 (is either ...the number that records show , was originally put in your chassis ?).

Is there any reason to think that your car was special in some way. Motors and chassis that were built away from the normal production areas sometime have strange stampings that can have font digits normally used in other model years & other stamping locations/applications.

I am not saying this is the case , just that I would study it closely before I made up my mind conclusively.

The date stamp area looks to be filled with some grime. I wonder if this would look different if this area could be cleaned up better.

Ratbox,

The area you are speculating contains a '3' looks to me to be a casting defect in the raised line between the week and year. I will crawl under my cars and see if I can make this out of '73 and '71.

Great Fryardds ,

I do not know about the earlier cases. But on the 1979 I posted (obviously a replacement case , and I have a 77) , the week & year numbers seem to be cast in & protrude out from the case. I believe when you look at one of these earlier cases. I don't think they are stamped . I think they are too small for that , I believe they would be from a small removable plug that goes into the case casting mold that has the numbers corresponding to each week of a year in the plug.

Actually when I look harder at Mattia's . I see I was fooled, the circle is a depression and the bar and small numerals are raised up from the depression circle. Just like on the later ones.

In the bar of mattia's casting date . What I thought looks like a 3 , is probably slag as you say...that makes more sense and aligns with the later cases I am looking at. And on mattia's case though the material under the bar seems to all be the same color.... not filled with any grime (and could not be if the numbers protrude as I think they do) . The last two digits of a decade (signifying casting year) do not seem to be there. But that is just what my eye sees. I would think normally a year should be there. I will try to look at any others I can , & take photos if possible.

Unfortunately if your looking at motors with exhaust & tubes installed , getting a close look is not easy. Obviously a photo is even more difficult.

Yeah, I raised the rear of the '71 and it is as you describe, very difficult to read the date marking and is impossible to photograph.

I used a dental mirror (I've got a few of these around;) ) to view the mark. The circular depression w/ a center bar is the same, but that is where the similarity ends. Below the raised center bar are 4 tiny protrusions organized randomly it would appear. There are 2 tiny raised symbols above the bar which don't look like numbers but I don't really know what they are. This is the right halve of the engine, which is a 3R casting.

The other side is truly impossible to see well, even with a mirror, but I could tell it has 5 raised protrusions below the bar. This halve is a 3R casting also.

Someone with access to a engine case or just one out of the car will have to help out. I am very curious now about what this mark means.

It is obviously a system of dating that is prior to the one that was in effect by 1977 (the example I have, that yes I had to use dental mirrors also to examine as it's a complete motor with auxilarys attached). If mutiple examples from each year are examined and chronicled. Then not only will we be able to figure out when the switch was made from one type of marking system to another. But also should be able to figure out the legend to decode the pre-numeral type.

Ratbox,
Double cheking I can confirm what you thought looks like a 3 , is slag. There's no digits for decades....so no way to understand my engine block belongs to (probabily is 7R from non carrera 2.7).

Now I have all engine parts from carrera 2.7 (MFI, heads, cylinders, cams) but not the original 911/83 block: how you evaluate the car value from originality point of view?

Do you suggest me to search for original 911/83 engine block? What can be the right price if any chance to find one in original and mint condition?
Thanks all of you for your assistance and patience to follow my case.
mattia

mattia,

If you wish to get a set of 7R cases , that were originally built as a type 911/83 motor by the factory for added value to your car. Then the only one to logically get is another 1974 MY set.

As to cost ? I can only tell you that I noticed last year on the early S forum, that someone posted and sold a complete 1974MY 911/83 long block (in unknown internal cond.) . They were asking 6500 US. I do not know what the final sale amount was. But i'm sure that amount , or very close.

That is only one sale , so it does obviously not show a pattern for determining value. And one item can be worth more or less from one person to another (needs and wants).

Buying a 2.7 and have a question on the case number
 

Hi, I'm buying a 2.7 rebuilt motor. As I understand it it came from a 74 911. The case number that was given to me is 9141933, but that seem not to be in the range from the research I've done. Can anyone tell me if this is a valid number? The motor is assembled and packed already.

The engine serial number should start with a '6', not a '9'. Second digit is for the model of the car, and third is the year. Last four digits are the sequential numbers for the engines made for that particular model.