Rare MFI Injector

[2.5MFI]

You just don't get to see one of these often. The short one.

[Flieger]

What's the application? And difference in performance?

[2.5MFI]

Application is for the 917. I ultrasonically cleaned the set of 12 and then did a pressure test. I then flow tested the injectors and saw a perfect cone spray pattern from 1,000 rpm to 8,500 rpm. I have tested many standard 911 & Mercedes MFI injectors but have never seen such a perfect cone spray pattern as these. Tom from Ed Pink Racing Engines sent them to me for cleaning & testing. Frank Honsowetz and his team at Ed Pink Racing are rebuilding a 917 engine for a customer.

[MTemp]

Bit of a hijack, Mark, but can you tell me the significance of the 3 digit code stamped on the hex-face of the normal injector? Is it a manufacture date stamp? If so how do I decode?

Thanks
Mick

[2.5MFI]

Mick, The three digit number that is stamped on the hex flat is a date code. It's similar to the date codes on the MFI pump s/n tag but a little harder to figure out because after the last MFI pumps built, Bosch continued to produce MFI injectors with later date codes. Photo below shows #770 on the hex. At the Porsche factory during engine assembly with MFI, the mechanic would take new Bosch injectors and with a electric scribe or something scribe the last 3 digits of the MFI pump serial numbers along with the cylinder head in which it was installed. Photo below shows a set of 6 injectors with the numbers 1-313 to 6-313 scribed on the injectors. A little hard to see but you can make out the 124 date code on one of them also. If you find an injector with only a stamped date code on the hex and no scribed numbers, it's a replacement set that was installed or a new one off the shelf.

[edmayo]

Always wondered what the 'electric pencil' numbers were, thanks Mark!

[MTemp]

Yes thanks Mark. I have some of the 'electric pencil' scribes on mine as well - not all if I recall correctly.
Is there a reference you can point me to to decode the dates?

Mick

[2.5MFI]

Mick, I have the code breakdown filed somewhere at the shop. I will try to find it when I have some free time and post what I have.

[2.5MFI]

I found the Bosch date code sheet. This applies to other Bosch products as well, but not all.

[MTemp]

Perfect - many thanks Mark.
I found one of these sheets online a year or so ago, but I cannot for the life of me find it now!

Mick