beryllium

Hi
can you light me?
the J&S is able to retard ignition when knock detecting,ok,but is it able to add advance compared to the genuine maping when no knock detected,or just find it again?.
exemple:when i fill octane booster in my fuel tank,knock is moving away.
will the unit add advance ?
to keep the engine alive is a good thing,but increasing also torque and power is a better thing.
can the J&S do the job?

nom

It won't advance past the ECU set levels, no, only retard from them.

Andy.F

So you set the advance a few degrees too far advanced and it makes best use of whatever fuel you run

JB Any chance of removing the delay circuit in the knocklink display ? I found that listening through det cans whilst watching knocklink and J&S display was giving mixed messages. I believe the knocklink delay circuit is to hold on the LED long enough to be visible but I'd prefer it was only lit during actual det, not just a single 'tink' that the J&S has got under control by the next cycle.
Relative to the J&S and cans, the knocklink provided a delayed/extended reaction but enough to make you want to lift off or adjust something.

Andy

nom

But you're a bit stuck if you can't adjust the advance
I think one of these things might be worth a go too - I just fear for my gearbox
Maybe I'll see if I can get 400bhp+ on NUL with WI helped by one of these J&S things - might be a giggle...
...or cost a new engine

John at J&S

Hi to all.

We can add an additonal retard mode to the software. I need suggestions on the specifics for the Subaru application, before I start shipping units for the group purchase.

Here's a description of the additional retard function:

On the 1ch/2ch units, mode switches three and four are normally used to configure the unit to work on one of four vehicle types. If we know in advance the vehicle, those switches could be used in another way.

For example, we could program a mid-range RPM retard/advance function. In our Ford Focus application, assuming the boost exceeds 4psi, the unit retards the timing, starting at 2500 RPM, and increases linearly with RPM, maxing out at 3500 RPM. At 4000 RPM, the unit starts re-advancing, and is back to the stock setting by 5000 RPM.

Switches 3 and 4 let you select (for example) 0, 2, 4, or 6 degrees of mid-range retard.

These RPM start/stop points and amounts are only an example. They are not user programmable, but I can change them when I program the unit. If you choose different break points, keep in mind that the ramp up/ramp down delta RPM must be equal.

For example, you could specify start retard at 4250, reach max retard at 5000, start re-advance at 6000, and back to stock at 6750. In this case, the delta is 750 RPM.

The mid-range retard is also modulated by MAP. If boost is less han 2psi, no RPM retard. If greater than 4 psi, full calculated amount. Between 2 and 4 psi, retard is proportionally less.

Denmark

iTrader: (2)

John,

I think that the only thing we need the Safegaurd to do,is to retard the advance when knock is detected,and we don´t need it to retard boost!.

I can see that Mr.banks ,had a problem with to much retard at around 3000rpm ,when flooring it there,maybe it can be made so it will only retard over 3500rpm ??.

This is just a example,maybe other/JB have some inputs??

Regards
Skassa

john banks

Thing is, at 3000 RPM my engine can det as it can be at 20 PSI.

Denmark

iTrader: (2)

Okay,

That´s not a option then.

Skassa

beryllium

john j&s
in europ almost all the scoobies are turbocharged from factory so the genuine ignition mapping is a good base.
we don't need to program retard according rpm and boost,only let the safeguard retard if knock as says skassa (and add a bit -if possible- with the "small" TD04)

Charly

John at J&S

oh. I did not know that.

Our V.0 option deletes the onbord two bar MAP sensor, and is a basic knock retard box. V.0 option saves $45 from list.

This option requires a connection to an external MAP signal, which is used to arm the knock detector.

The unused boost retard "rate" **** is used to set the knock enable point, with respect to MAP voltage.

I need the spec of the stock MAP sensor:

Key on, engine not running, record MAP voltage:

Apply 10 psi from MityVac hand pump, record MAP voltage.

Denmark

iTrader: (2)

okay,
Is there anyone that knows what the voltage of the map sensor is at this boostlevel????

We need to know for the groupbuy!


Skassa

john banks

MY99/00 MAP is 0.88V at complete vacuum, 4.84V at 2.8 bar absolute, linear in between, atmopspheric is usually about 2.3V, idle is usually about 1.3V. It is "almost" a 3 bar MAP sensor.

John I hope I will not break the 2 bar MAP sensor in my J&S by putting 2.4 bar absolute to it? Presumably it will just saturate?

nom

John - how are you monitoring the retard on the individual cylinders? I've been looking at the J&S info & trying to figure this out! There's a simple LED that shines to varying intensities, and also an add-on guage that shows the actual amount of retard, but mixes all the cylinders up (although showing them seperately, if that makes sense?)
Just wondering how you're managing! Sorry if you've said it on the other thread, but I didn't notice of you did...

John at J&S

You are not able to tell the amount of retard on a given cylinder from the bargraph display.

The signal that drives the bargraph is a stepped analog voltage, which changes every spark event.

You could use an oscilloscope, with one channel triggered by number one sparkplug wire, and channel two looking at the knock retard voltage from the monitor jack.

Or you could use our KnockFinder box:
http://www.jandssafeguard.com/knockfinder.html

nom

Thanks - found that & thought it might be the only way!
It's all a bit heavy-going for me then - think I'd just 'make do' with it doing its job & not telling me everything - no problem!

Denmark

iTrader: (2)

I will just mount the led from the box,a place were i cn see it then you know if there is a problem(as the led glows brighter when more advance is removed)

Skassa