Englene number

[Lexn]

I have bought an 2.7 rebuild MFI engine with number 612...5 and engine stamped 911/91 which indicates a 173 1/2 type, but the nummer series indicates a US 1972 T CIS So what is wrong? 911/91 is casted but engine nr. Seems tampered with or maybee manuelle marked, can Someone explain.

Regards lexn

[pors1968]

Engine number612 is 1972 engine 911/91 cis us 73 but engine 612..... and 911/61 72T

[panama911]

According to some other forum... 911/91 went from 6133001 to 6136092.

It shouldn't be 2.7, shouldn't be MFI either; your case (911/91) was supposed to be a US 2.4 T CIS.

[pors1968]

911/91 is a 1973 case but 612 is 72T case kind odd.

[jrbennett]

Are you sure it's not 911/51 or 911/61?

That would make sense for a US 72T with MFI 5speed or sporto

otherwise I would guess the number has been re-stamped

[Henry Schmidt]

A huge number of 2.7 engines exploded during their early lives do to over heating.
Although not all but some of the 73 cases were 7R castings with a 2.4 spigot size.
As a 7R case, it makes a great replacement case for building a 2.7. All that is needed is to bore the spigot from 94mm (?) to 97mm if memory serve me.

[Lexn]

Yes I´m quite sure that is 911/91 but the engine number looks a bit odd, have heard that is a star fore and after, but not on this, what should be the reason for a false wrong number? other than stupidity.

[pors1968]

Take a picture of engine and serial number will be easier to speculate.

[Lexn]

911/91 looks ok but the other one ?

[Turbo_pro]

Serial number is a restamp. Might be a dealer restamp but generally they use German number stamps.

[pors1968]

It look like dealer restamp .Number look same size on serial and internal.

[Lexn]

Just found more nubers on my case 901,101,102,3R this indicates a 2.2 case, haven´t taken it apart because it runs fine with no oil spill, but I bought it as a 2.7 rebuild, but is this possible with a 3R case?

No I got a lot of different series numbers 911/91, 6120015 and 901.101.102.3R what should I think this is, maybee take it all apart.

[JJ 911SC]

Originally Posted by pors1968

It look like dealer restamp .Number look same size on serial and internal.

Oui, no "*" on either side of the serial and the "/" on the engine type is rather long

[pors1968]

2R and 3R =70 -71 2.2 3R 4R 2.4 72-73 you have to look both side

[Lexn]

Other side is 901.101.101.4R and what is that, can anybody tell an amatør what type of block this is, I am a bit confused, have patient please

[pors1968]

Like post 14 3R and 4R is 72-73 that goes whith serial number 6120015 1972case 2.4

[Lexn]

Ok thanks then I understand, I have a rebuild 2.4 Us case with 2.7 syl and perhaps a reinforced case, maybee reasons for the 911/91 stamping.

[pors1968]

I think 911/91 they stamp is 9 is upside down should 911/61 the 9 is error whith case number 6120015 but you may have 2.7 barrel whith 2.4 crank is a 2.7L

[E Sully]

Neither the 911/91 or the serial number look anything like original factory.

[pors1968]

Agree it a restamp by who knows.Like post 11and 13