Date: Thu, 24 Sep 1998 22:28:45 -0500 I've known John Pizzuto from J&S Electronics for a couple years now. I
used his Safeguard knock sensor on my turbo Miata with good results. Better knock
sensor logic than the system that came on my TEC-II. Brian Richard also has good
experiences with his Safeguard for the FD. Abel and Adam S. use them on their
drag cars too. SCC's Project RX-7 will be using their system in the near future.
J&S's new design (functionally the same, just a lot prettier now) will also be
availabe in a few weeks. Cheap insurance for your rotary, it would seem. I've
heard that Adam has said it has saved his engine many times... I've had no
first-hand experience on rotaries yet...
J&S can be reached at 714-534-6975.
________________
Date: Thu, 26 Mar 1998 21:56:07 -0800 I have a J&S unit on my car, which is an '85 GSL-SE with an after market
turbo. I also have the read-out for the amount of retard being dialed
in. The object is to set it up so that you get no reading under max
boost. This is as opposed to setting it up to rely on it routinely to
retard the spark under boost. You shouldn't see it activate unless you
are messing with things, and have probably gone too far. You will know
it is right if you have established a baseline where you know boost is
about the max you can safely run. Set the J&S unit to activate at any
point above that.
Of course, if you hear detonation, you need to make it a little more
sensitive. My unit is set so that the screw slot is on a line between
11 and 5 on a clock face, about a quarter turn clockwise from the least
sensitive position. I have also discovered that if the unit is too
sensitive, it will retard the leading plugs past where the trailing
plugs fire. For some reason, this seems to cause pinging.
I have not hooked up the yellow wire because I have not had a problem,
however, I do occasionally see a flicker on the indicator when the car
is off throttle--especially if I have just completed a high boost run.
It isn't worth worrying about.
If you don't already have it, you should get the read-out to tell you
what is going on with the knock sensor. As an alternative you can use a
volt meter hooked up to a mini jack and plugged into the front of the
control box. J&S makes a version of the read-out with a parallel line
of LED's that is an A/F meter. The combination meter takes up very
little room. I wish I had gone that route. Twenty-twenty hindsight,
eh?
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Date: Wed, 04 Nov 1998 13:46:17 -0500 J&S Electronics has visually redesigned their knock sensor for the 3rd
gen RX-7. It now looks like a pretty anodized box now and far more
presentable than the previous plastic units. For those who don't know,
Adam and Abel both use this unit (although they don't like to tell
anyone.) It has saved more than one motor, from what I've been told.
For a engine that can be destroyed by one knock, it looks like a good
precautionary measure since the stock knock sensor doesn't seem to have
the necessary authority range to prevent knock on a modified engine.
John Pizzuto as J&S told me that Mostly Mazda (925-686-9055) is the
exclusive dealer on the West Coast.
The kit includes a electronic control unit (with sensativity
adjustments) and a microphone. Installation is simple and requires very
little wiring. Costs $425. An optional plug-in a/f ratiometer and
ignition retard monitor is a $150 option.
Blatant plug, I know, but I've heard and seen good things about this
product. The guys at MM consider it a highly recommended upgrade for
those with a free flowing and higher boosting rx7. A good idea for the
track too. I used one on my 330hp turbo Miata will good results-- stock
bottom end for 50k miles before the car was totalled.
FWIW, the product will be covered in Part III of SCC's Project RX-7
(Feb. issue)
__________________
From: Shiv S. Pathak [SMTP:shivp@worldnet.att.net] Just got back from some Project RX-7 dyno testing at Superior Dyno
Service in Hayward, CA.
(non J&S stuff snipped)
We also tested with varying degrees of J&S sensitivity, from no retard
(insensitive) to 4-5 degrees retard at certain rpm (pretty darn
sensitive). Surprisingly, no measurable hp change either way.
It seems the only place that the J&S wants pulls out timing is at
3000rpm when the secondary injectors turn on and when the 2nd turbo hits
(sudden change in load). Worked as designed... very nice. However,
even when the J&S was disconnected, car was never close to knocking, but
it nice to know that the J&S is listening carefully-- ready to pull out
timing in case something goes wrong. When we up the hp more and get
closer to the fuel limits of the car, it should be very helpful.
Anyway, it's a nice safety feature to have on the track when the car is
under heavy loads for long periods of time.
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From: Shiv Pathak
From: "David H. Lane"
From: Shiv Pathak
Sent: Tuesday, December 01, 1998 9:20 PM
