So should someone get the new dynotune lean shutdown switch or just get a FPSS. Is there any problems to running both or is it just overkill. just wanting to spend them oney in the best location.

What are you guys running as far as safety with good experience.

 

I like the fpss.

 

As far as safety devices comparing these 2 items are like a Ferrari to a Kia. A FPSS, yes we sell those as well, will shut off your nitrous if your fuel pressure drops below a set value typically 35 PSI. You can run lean, damage your motor and your fuel pressure can still be fine. You can have good pressure but not enough fuel volume your FPSS wont help. If you have a clogged or faulty fuel solonoid the FPSS wont help. You have a clogged fuel jet the FPSS wont help.

Features included:
--Microprocessor contolled
--Built in Air/ fuel ratio display(narrow and wideband)
--Built in TPS (WOT) Switch
--Peak and Min A/F memory during the run
--Multiple outputs 12V and Ground
--Multiple Trigger inputs 12V and ground
--Programable trip points
--Adjustable delay to let lean spikes settle

In my opinion for the price you would be crazy not to run one.

Dean

 

Definitley go with the Dynotune shutdown switch, for all the reasons Dean listed above. They are even relatively comparable in price, so why not.

 

Just out of curosity...
If a lean condition exists and is/was present and is sensed by the o2 and the nitrous is shutdown...
Won't 99% of the time it be too late for your motor?

 

Assuming the a/f shutoff responds fast enough, it is 100x's better than fpss. Its not a terrible idea to have both.

 

So one would be definatly be fine to not run a FPSS if they have the dynotune item.

It just seemed like it was too good to be true at 99 bucks.

 

Actually the electronics are so fast, fractions of a second, it will work the majority of the time. Most failures we have heard about with systems the lean condition builds as the rpm rises. So you will shut off before the lean condition turns to a drastic situation. If you have a catastrophic failure which is rare obviously its impossible to cover every situation. With the FPSS you will not shut off until you hit that catastrophic situation which as you noted is typically too late.

Dean

 

You know...I might actually give this little thing a try.
Thanks for the response!
Can you let me know if it will work with the output of the FAST dual wideband that is already in my car?

 

Well you sold me on the dynotune shutdown switch. I will ordering one shortly.

 

I have both.

You can set the AFR shutoff point to whatever you want. Most people run their nitrous system in the 11's, so 12.2-12.5 would probably be a perfectly fine place to set it at. Not so rich that it trips all the time, but rich enough that you could probably run your nitrous system there anyway with no damage.

It also has a built in feature so it knows when the system is actually SPRAYING. This way, you can tune the car to run 12.8 on motor, 11.8 on spray, with a trip point of 12.2, and it won't start blinking LLL every time you stab the car N/A.

 

Thats the part that I really like with this unit.

 

i think you guys have sold me on it too. i'll be ordering one in the next go round of parts ordering

 

I too will be getting the Lean Shut Down Switch soon also, but it is not $99 it's $140 shipped with the led indicator. I will be running the FPSS too. I also think it's a good idea to get a wideband O2 setup with controller to take full advantage of this product so I figure on spending around $330 for the Lean Shut Down Switch setup.........

 

I didn't know about the peak and low playback. That makes it a must have for me. I have a hard time shifting my eyes over to my WB gauge when going down the track, so this would give me a little more comfort.