info needed on J&S knock box
 

I have a 90 1.6 and i bought a used kit. When opening it up i discovered it came with a J&S knock controller. I know some of these are pretty old so my question is... Is this obsolete to the newer "simpler" systems like the bipes or msd? Im just wondering if i should keep it or sell it and buy a cheaper one.

I know very little about this unit, whats its features exactly? the site is somewhat vague on which unit i actually have.

I will be only be pushing around the stock 6psi or so.

thanks for any help

this is the piece in question.
https://www.miataturbo.net/attachmen...ine=1371782201
https://www.miataturbo.net/attachmen...ine=1371782201

The J&S box incorporates an actual knock sensor.

The Bipes and MSD boxes do not- they simply retard the ignition timing by a fixed amount based on manifold pressure, regardless of whether knock is occurring or knot.


(rimshot.)


The J&S products, while somewhat old, are fairly high-end.

The Bipes ACU and MSD "Sebring" boxes are just as old, and were vastly inferior even when new.

Interesting. I'll have to look into it more. I found their site a little confusing to figure how this specific unit operates. How to adjust it and such. I'm not too knowledgable about tuning so I hope this unit is "too good " that I won't be able to understand it. Haha

A lot of piggyback timing-control units came and went during that period of time.

The various J&S products were generally regarded as being at the upper-end of the spectrum in terms of quality and performance, whereas the Bipes ACU and MSD Sebring were, shall we say, more... budget-conscious.

They did proper windowed knock detection, per cylinder retard etc. They are miles ahead of most of the current budget orientated offerings.

That supposed to be a pretty good and still relevant knock controller...

awesome, thanks for the help. i managed to talk to John from J&S. He's helped me a great deal with the unit as i had no instructions, and little wiring that went with it.

Seems like this is a good device since it actually monitors instead of only reading boost and increasing on the grounds of that only. I will definetly be incorporating this in my setup. thanks everyone

Im running a J&S and, while it is still AIDS, it actually works very well. if you have ANY questions at all about your particular box, contact jpizzuto@jandssafeguard.com

he is VERY helpful, and willing to lend a hand (or email) he will answer anything you need, and even email you schematics for everything. i dont have the system you have, i actually have what they call the 'Miata Black Box' but they all work well... mine was just designed specifically for the miata.

although the J&S is a great system... you really should look into getting a megasquirt setup... then there is no need for all the AIDS

EDIT: sorry... i should have read... you already contacted him... hahahaha :P

Even with something like a Megasquirt, the J&S box is still relevant. It's a good knock-sensor-decoding systemm, and all else being equal, will permit you to run more timing safely.

well, thats good to know.... because i was about to strip mine off the harness...
so, being that my MS will be PNP, would i have to advise the builder of the system that i have the J&S installed? would that affect the ECU at all? i was thinking the J&S would try to retard the timing, and the ECU would fight its decision making process. (sorry about the noobness, im trying to learn all i can about MS before i take the plunge)

the MS won't have a clue about the J&S retarding timing.

awesome... that makes my move to MS that much easier.. i was hesitating, because i didnt know if i was gonna have to strip down the harness befoe i could ever use it. everything is soldered in very nicely. very cool... im really looking forward to this...

I use the J&S safeguard with my MSPnP

You will be able to hook it up with your MS providing the version you have is the 2 channel version (direct control of coils) called Ultra Safeguard. There will be dip settings on the side that will give you the choice of single (cam angle sensor) or 2 channel mode.

If your J&S is the older 1 channel only version sell it.. It wont work with the standalone.

The J&S wired direct on the coils from the MSPnp is DECADES! Ahead of any diy Detcan setup for knock control.

If you don't want the unit to directly control your ignition, you can use the "monitor output" as an input on your engine management. I've got mine setup to retard timing, add fuel, and reduce boost depending on how much knock it is picking up.