Farnsrocket

I searched this and pretty much think I have it figured out, but I want to be certain.
Which wires don't I use from the J&S since I have Hondata 4b........the two MAP wires (#10 and #11) and the yellow #9, and then connect everything else??
And of course, don't hook up the vaccuum line.
I am also guessing it is safer to have switch #1 up, allowing more retard.
Last thing, which option do most of you recommend individual cylinder retard or all cylinder retard, again, I am guessing all cylinder is probably safer.

Thanks!

JT

Ideally, you would want a J&S classic to use with the Hondata, as many of the Ultra functions are not needed. However, if v2 is what you have, then here are some suggested settings.
1. Don't hook up the J&S MAP limiter function. The Hondata takes care of that. However, you do need to route the MAP sensor to see boost per Hondata's instruction.
2. You need to hook up the vacuum line. Otherwise, the J&S will always perform mid-range retard function. However, if you choose to leave the line off, then you should factor the retard into your tuning.
3. Set switch 1 up for insurance.
4. Set switch 3&4 down for the max. of 2 degrees rpm retard.
5. Disable the boost retard function by turning the boost retard start point fully clockwise, and turning the retard rate fully counter-clockwise. You guess it. Hondata is controlling this one too.

Farnsrocket

Thanks JT!
I have a couple of questions.
I am confused on the vacuum line? Why does it need to be hooked up if the Hondata is controlling boost related issues?
The directions say Honda's must have switch 3 & 4 up.

Thanks again!

JT

Switch 3&4 are for programmed rpm retard. Because you have a Hondata, you want to set it to the lowest setting and let Hondata manage this portion of the retard function. Switch 5&6 must be up for Honda not 3&4. The J&S has a built-in feature that it retards timing according to engine vacuum. By not connect the vacuum line, it thinks the engine is at atmosphere pressure and retards timing. Ideally, this line should connect to a source that always has vacuum when used with the Hondata setup. However, like I mentioned earlier, you can leave it not connected but factor in the retard into your Hondata tuning.

Farnsrocket

Ok, well, there isn't a switch #6 and the directions say to put switch #5 down. Where did you learn this information?
Thanks!

JT

Hmmm... unless your version is different or you have a newer design unit, you should have the same switch settings... Here is the Ultra instruction that I have.

John_at_J&S

With the vacuum line disconnected, the unit thinks it should listen all the time. Light throttle or decel can cause false knock detections. The vacuum line is required to "arm" the unit. The knock sensor is ignored if the RPM is less than 1250, or the vacuum is greater than five inches.

There are two software versions of the new eleven pin unit. The first half dozen or so were Honda specific units. S3 and S4 selected mid-range retard, as in the earlier units. This should be indicated in the instructions.

The mid-range retard was deleted on subsequent units. If the instructions say to set S3 and S4 up, you have the latest version. S3 and S4 configures the unit for Honda, MR2, Miata, Subaru/ Eclipse.




[Modified by John at J&S, 10:42 PM 7/27/2002]

JT

Thanks John for the info! Btw, any chance at all to reintroduce the Ultra v.0 or the classic safeguard?

RATEDR

JT: I have the classic version and it might be for sale very soon.

Farnsrocket

Thank you everyone for your help!

JT

RATEDR, I just IM you.