Aquamist HFS-6, low impedance injectors and motec M600
 

I have an 87 Ruf BTR being re-done by TurboKraft and I need some help. I bought a NIB HFS-6 system from another member at Jeff's recommendation, I am using a motec M600 ecu and low impedance injectors, in this configuration the system will not trigger off the IDC because the voltage never drops on the injectors any suggestions?

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Does the 87 Ruf uses low impedance injectors from factory?

The H6 (discontinued 3-4 years ago) was not strictly designed to run all types of low impedance injectors due to different "peak and hold" technique used by different companies. You have a better chance of success if you go for the newer HFS-4.

Spoke to Jeff, he did recommend the HFS-4 so for some reason you have decided to purchase a second hand HFS-6 (NIB). If you had told Jeff at the time of enquiry that you are running a Motec and low impedance injectors, he wouldn't gave you a lead for a S/H HFS-6.


Suggestions:

1. The best way to get around this is by driving the H6 directly from a separate PWM output off the motec.
2. Use resistor pack (6-8 ohms).
3. Run the system via manifold pressure sensor instead of IDC.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Thank you for the fast response Richard. The discussion on the injectors was never fleshed out, at the time I was seeking the HFS-6 because we were discussing running six water/methanol ports on the six long intake runners. I was not aware that the impedance of the injectors were a concern, I did on more than one occasion discuss the fact that I was running Motec, moot point now. The system is installed, bought and paid for, what are the liabilities I face if I run off MAP instead of IDC.

Thanks again for your kind consideration,
Best regards, LP

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

I didn't think he ever recommended the HFS-6 to you, just gave you a lead to obtain one - he doesn't have to do that. Are you say he is liable for help you? Motec can run low or high impedance. I know some people runs 2000cc high impedance injectors from ID.

Anyway two choices:
1. Map sensor
2. Motec dedicated PWM output. (copying fuel map)

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Cross post. No, I am not saying he is liable, I was asking what problems I could expect to encounter. Jeff has been great this is not a blame game, hardly, I need your help why would I castigate your dealer. See below my response on the other thread.

Pardon me sir, I will not engage in a war of hearsay, I hold myself to a higher standard. I asked for an HFS-6 discussed my pie in the sky dreams to have my car back and the results I could expect. Jeff gave graciously of his time made some suggestions, returned several calls and because your HFS-4 was not yet available -if my memory serves me right and kindly pointed me in the direction of two HFS-6 systems, one was used and the other NIB I opted for the latter so there would be no questions as to reliability and so forth. Unfortunately here I am in a place I was hoping to avoid for the sake of communication this could have been averted. I need only to find the way forward, I am not here to bash anyone, Jeff has been great and the board is a repository of tremendous information. Thanks Richard, you guys make the best kits out there and as far as I can tell you support and represent the product well, not an easy thing these days to get great support. FWIW I bought the system in November of last year. Thanks again.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

I have just spoken to Chris, there are several options to bring this forward. He is now looking into it.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Many thanks.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

As Richard says, do you have a spare PWM on the Motec to drive the valve directly from the Motec ?

Or just fit some high impedance injectors.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Fitting new injectors is easier said than done, lots of money on balancing injectors, and of course the injectors themselves and a complete re-tune. I think the shop has found a way forward.

Re: Aquamist HFS-6, low impedance injectors and motec M600
 

Didnt realise the car was already running and tuned. Although 6 new injectors shouldnt cost that much really unless you are into the ID1000's or 2000's