Richard L

iTrader: (5)

The 2 second "grace" period is not as bad as you imagine. There will be extra fuel injected (acceleration enrichment) during this period as well as some timing retard from the ECU.

The in-between "re-triggering" delay during gear change will be shorter than 2secionds . The delay will depend on the gap between the two triggers. vary between 0.5 seconds to default.

So far, since 2005 when the first version of the DDS3 was launched, no one has contacted us to modified this.

From the Mid May onwards, the DDS3 gauge has "Zero" delay for pin9/10. But pin11/12 has a delay of about 60 milli-seconds. (with a 10K resistor compared to a 390K resistor).

dudical26

iTrader: (17)

I don’t think this is entirely true. If the Alky fails and the engine starts to knock then yes some timing will be pulled however I don't believe that our ECU adds any fuel to compensate for knock. Additionally at WOT it runs in open loop mode and will have no idea it is running very lean.

TTP Engineering

iTrader: (465)

As a vendor I was not going to correct Richard, but you are correct. It takes a long time of continuous knocksums to lower the octane value in the ECU. IMO measured in minutes, not seconds or milliseconds. At that time the ECU starts to move toward the lower octane fuel mapping (if your low and high octane maps are not the same) and start to interpolate between the high and low.

ryan0

iTrader: (2)

as always.. awesome support and answers to our questions.

i will highly recommend your kit.



how do we tell which version we have? mine just came, but who knows how long it was on a shelf.

are there plans for some kind of pot to make it user adjustable? and if so, is there a retro-fit path?

dudical26

iTrader: (17)

Do you think it would be a good idea for me to modify my HFS-5 system as Richard has described to reduce the delay time. Your answer will be seen as your opinion on a technical question and not your opinion on Aquamist's products.

As an additional failsafe, I just wired in my ZAVT which I bought from you last week. I only have it set up to blink and beep though, no relay trigger as I have the HFS-5 doing that.

TTP Engineering

iTrader: (465)

Personally I use the zeitronix for ALL safeguards, however Slowcar (Abner) uses both to an extent for overkill protection.

I think he is using the aquamist flow sensor + zeitronix 0-5v aux input alarm to trigger boost cut.

Furthermore with the zeitronix I am pretty sure he uses it the way we do with an alarm if EGT temps exceed a preset amount.

The combination alarm we use is IF BOOST> 24psi AND TPS> 70% AND AFR 12.5>, then the alarm triggers and cuts boost as well.

Abner can better describe how he uses the systems.

Richard L

iTrader: (5)

TTP and duducial26,

I totally agreed with all the recent posts. I was just thinkng if there are some saving grace to make it an uneventful 2 seconds.


TTP, when can I buy the Zetronix from you?

Richard L

iTrader: (5)

If you tell me the serial number of the flow sensor, I will be able to put a date of manufacture.

All system with a flow sensor starts with a serial # above 3000 has a 60ms delay.

dudical26

iTrader: (17)

Richard - I personally think that a 2 second delay means that my failsafe is less "safe." What do you think is the lowest I could set the delay to on pin 11-12, without creating a fale trigger situations during gear shifts?

Also how hard is it to remove the resistor and install a new one as I am somewhat clumsy when using a soldering iron.

Richard L

iTrader: (5)

The removal of the component on the guage is straight forward.
If you are not in a hurry, send it to me the junction box and i will modify it for you. Better still, I send you a the latest and you can send me the old one back by post.

dudical26

iTrader: (17)

That would be great I will send you my shipping details by PM.

SlowCar

iTrader: (4)

i went with a sensor that will remain "good" - and will react when there is a disruption to the flow of injectant. I'm not very good at scheduled maintanence of replacing things...eg oil change

i did not have good luck with my turboxs wideband sensors on my VIII...and with the exposed egt thermocouples, they degrade over time due to high temperature, oxidization, carburization atmosphere and eventually fail due to breakage.

on my aquamist/zeitronix failsafe, i set
if boost is greater than 10psig AND flow sensor voltage lower than X volts, open mac solenoid and drop boost.

one advantage of using the dds3 is, you operate the failsafe on a window region - you can set the unit to activate failsafe if injectant flow is too high - in the case where some run internally mounted hago nozzles that might loosen and allow greater flow than normal

ryan0

iTrader: (2)

so im assuming this is the 'recommeded' path for us '2 second' people?

ryan0

iTrader: (2)

so we want to match the flow of the restrictor and the jet.. but in the end its better to be a little over on the restrictor?

there seems to be a big flow jump with the included restrictors.

Richard L

iTrader: (5)

I am not holding my breath for those who want to drop the 2 seconds to ~60ms. The 2 second is only at the triggering point, where most people will set it before boost ramp.

I still think the fuel enrichjment during the boost ramp is so over fuelled to a large extent, more than enough to prevent the engine from going lean. Previous discussion was side tracked by knock sensor and the ability of the knock correction or engine ability to switch fuel map due to knock (low octane fuel).

The enrichment curve has nothing to do with the above mentioned. The decellereation map also allow some fuel to be injected to "wet" the runners ready for the next WOT. This is the "little inbuilt safeguared" I was referring to in reference to the 2 second grace period.

What serial number is your sensor?