ECU/AFM conversion on early 944

[porschemech]

Hello all
Does anyone know if when converting the 1984 944 ECU/AFM to the later 944 ECU/AFM require the later fuel injectors also?
Porsche service bulletin states injectors must match ECU or ECU damage can result.
Any advice or experience on this?
The ECU I am considering using has a Hypertech performance chip installed.
Thank you

[v2rocket_aka944]

*conflicting information removed*

[944 Ecology]

Yes, the later injectors are required with the later ECU.

[v2rocket_aka944]

*conflicting information removed*

[944 Ecology]

Originally Posted by v2rocket_aka944

color me curious, why do you say that?
i mixed and matched freely over the years without apparent issue.
i checked coil ohms mostly to make sure they weren't turbo injectors.

Different resistance values early vs late.

[originalowner]

Resistance the same early vs. late at 2.4 ohms. Flow rate on clarks and a table of bosch injectors I found online differ slightly, but both agree to an approximately 3.3% increase in flow for early ones.

[dkraven]

I have a late afm/dme on my early car, don't need to change the injectors.

[thekidd]

I didn’t need late injectors. Just AFM/DME plug and play. And it gets rid of the early 944 stumble