964 intake on 3.4 motor?

[asphaltgambler]

advice please from anyone who has completed this

[ischmitz]

I have not done this myelf but for what it is worth: I assume with stock motronic you are referring to your 3.2 Motronic. It's output stage uses current-sensing to limit the maximum current in the hold phase. For high-impedance injectors it simply acts like a switch. So it can drive both high- and low-impedance injectors. The high-impedance injectors just don't create the same demanding conditions.

The other way around would not work. You can not use low-impedance injectors with an ECU that can only handle high-impedance. So a 3.6 DME can not drive the 3.2 injectors.

I don't know what you mean by revised board. Is that the conversion from 24 pin EPROM to 28 pin? This will not make a difference.

Cheers,
Ingo

[911-32]

Presumably, if you use 964 injectors with a 3.2 Motronic, you have to remap to get the fueling right? I have a set of 993 injectors as well as 3.2 - are they high impedence like 964?

Thanks

[ischmitz]

Well, he has to re-map anyway with his changed displacement and the different flow characteristics of the injectors. I was more referring to the electrical compatibility. If you look for a drop-in replacement for the stock 3.2 injectors there was a lengthy and very informative thread here.

I assume the 993 injectors are very similar if not the same as the 964 version. I don't have the PET in front of me though to verify this.

Ingo

[asphaltgambler]

Yes, I'm planning on using the 3.2 motronic where the board is updated to the later '87 and up configuration. The mod is supposed to provied fuel enrichment on acceleration.

Steve Wong is the guy for this I'm told and his website may have more info

[ischmitz]

Yep, that's the upgrade to the later Motronic chip that holds the code and the maps. Earlier DME's had a 24 pin 2732 EPROM and later versions have a 28 pin 2764 EPROM.

[asphaltgambler]

Thanks for the updated info.................................for a moment there I was envisioning an additional $700.00 for new stock injectors.......................after I just had my 3.6 injectors sonically cleaned, flow tested and balanced