That should be easy to do, just give it the full 5 volts as the nominal amount, and then bring your entire timing map down by the 2.5V difference, (8 deg on an e6k for example), that would give you a full 16 degrees of possible retard on an E6k. and 0-40 on an E11/E8.

Since the trim plug supplys the 5 volts and just a guess, but he is probably taking that and stepping it down to 2.5 you could probably eliminate a few components by doing this.

Yep!
That will be me.
BTW. Mr Dickhead to you sir! :)

Great question! The answer is Yes, it is firmly and robustly clamped as to not allow for timing to be added.

The only way this output could go above +2.5VDC is if the Haltech's +5VDC sensor supply voltage was to raise. I have never heard of this happening and it would also cause all of your other sensors to read wrong too. The Haltech's +5VDC is merely ran through a resistor to drop to the +2.5VDC, so this part of the circuit is not complicated and relies on very robust components.

Justin

This is a great point and could be done.

Do we really need to pull more than 8degrees though? Would more people like this design? Maybe I will tinker with the idea of this....now I'm thinking of a design that has a switch (like the J&S) to be selectable...hmmmm....back to the breadboard

Justin

I would like the 5 V nominal design better because it would make the product just slightly simpler. Even if it isn't really required.

If your back to the breadboard how about a second channel that can enrich the maps using the fuel trim. Not sure if this would work on an E6k, that is having both fuel and ign trim active at the same time, but it would work on an E8/E11

So I would have to make one channel increase in voltage while the other decreased. hmmm.

Justin

I tested this over the weekend on my E6K and was successful in advancing to +6degrees and was able to pull to -8degrees. Thats 14degrees of total pull. The current design is capable of this too with the current built in adjustability.

The rebuild time is dependant on these adjustable resistances so the rebuild time is very short. I could change this rebuild time if people are interested in more timing pull.

If people dont mind offseting their base maps (or another trim map Air Temp Ignition, Coolant Temp Ignition) then this unit is cabable of pulling 1 to 14degrees of timing.

Justin

If I understood correctly.
The easiset way would be to reset the trigger angle deg. with the trim setup at full advance that way when the unit activates you can get the full retard range of the trim control input.

This would work, but all datalogs and real time readings from the engine data page would look advanced by that amount. I would prefer to change a trim map across the board so that the real timing still appears when logged or looked at.

Justin

True. :)

FS: Closed Loop Knock Control
 

I made another batch. I have one left for $75shipped 2-3day USPS Priority. Most international orders can be shipped for an additional $10-15. PM me.

Justin

Here is the thread I will update with the latest info:

https://www.rx7club.com/showthread.p...0&page=1&pp=15

Justin

I'd like to get one.

Back from the dead...Come on buddy make a few more for us...

Yes! :-)

I've sent a couple of pm's to Pistonsuk, and he replied one time saying that he was moving and would be a while before he could make another batch(but that pm was over a year ago). And recently I've sent one but he hasn't replied back. Maybe if enough people had more interest in them and contacted him by pm or email then he might consider making another batch for us. I personally want three of them asap!

We can probably gleam some information from the MegaSquirt manual site. It has some neat information.

MegaSquirt-II Knock Sensing

hey sorry for the delay.. PM'd ya back

-J

Knock boxes back in Production! Shipping 12/2010
 

Due to popular demand, I am going to make another batch.

Taking orders now, at this point I have 9pcs not spoken for yet. I'm waiting on parts; at the very earliest I will able to start shipping on 12/6/10.

$75 ea. Paypal accepted. Shipped 2-3day USPS. Comes with full install instructions.

Send me PM and I will confirm your order and reply with paypal addy.

-J

Knock Box Response Video:

Blue line is Output from GM ignition Module. Step pulse is caused by knock event. Yellow line is knock box output (instantly goes low ~0v causing Haltech to pull timing then rebuild slowly back to 2.5V 0deg timing).


<a href=http://www.youtube.com/watch?v=NaSrZqJ6s_8>Get your HTML codes here!</a>

hi mate will these work with a platinum 1000

I'm not that familiar with that one... if it has ignition trim input then you're in business!

-J

8 Boxes Left
 

Mike V got #9.

8 more left.

-J

PS2000 (and probably PS1000 as well) does have Ignition trim input and is adjustable for 0-20 degrees.

"With the optional trim module attached to an analogue input, the ignition timing can be adjusted with the trim module.

When the trim is centred, the amount of correction is 0°. When the trim is wound to the left, it will be at the most negative correction. When wound to the right, it will be at the maximum positive correction. The setup tab allows you set the Maximum Trim percentage"

If you set it to 20deg and Justin's box is producing 2,5Volts at no knock, you will have 20deg of pull at 0V.

Hey buddy, is there any way you can make an output for a led light so we can know what's happening-when the device is activated?

not at this point, it was a stretch for me to be able to build them again. sorry, no time/place for R&D.