GruvyTune

Ok. i've been pushing some aggressive A:F ratios 12.9:1 to get max HP. I have no evidence of detonation.


I have a J&S and its very finicky about noise. Seems with forged pistons, you have to set it to lower sensitivity.

MY safeguard lit up alot on the dyno but i think there is more noise on that than on the street. did you find that you can induce knock very easily by climbing a hill pushing 5th gear?? I would imagine that isn't a good idea anyway.

what i dont understand is, if you have your knock sensor light up, how do you know its working to retard timing? i mean if its lighting up, then its still knocking, right? I mean if its retarding timing to stop the knock then wouldn't the lights go back off again? does that make sense? how would you know how much to set the box to?


anyone with good experience using one of these?

Thanks
Torin

boomslang

Well, being in 5th gear going up a hill puts a lot of load on your motor. Increased chance of knocking.

Are you using the Ultra J&S? I used the Ultra for a while, depending on how many LED's lit, it would tell you how much timing was being retarded. It just retards/advances in cycles. It senses knock and retards timing. It senses no knock, and lets the timing advance to the stock point. It's sensing capabilities are extremely fast of course so very little knocking can take place before it retards timing.

On my old turbo lude I had an Ultra. No evidence of detonation when running, plugs looked great. The Ultra would go nuts even if I used 104 octane. I adjusted the sensitivity but it did very little for me. I ended up selling it.


[Modified by Inlinefour, 12:14 PM 9/1/2002]

JT

What you could do is to datalog a session when the knock monitor lights up and compare the timing difference with the ignition map for that particular rpm/boost level. The J&S starts to retard timing way before the knock becomes audible. If you have the ultra, then you also need to disable the boost retard function when used with Hondata.

I set my ultra to 20 degrees retard range for max insurance and retard individual cylinder for performance. The sensitivity is set to 9 o'clock. With this particular setting, I still see one or two cylinders retard for 2 to 4 degrees for about a second during certain boost situation. If you can identify when the knocks take place (rpm/boost), then edit the ignitioin timing for that zone should reduce the knock activities (assuming A/F is already done).

VaporTrail

I hate those J&S things. More of a bandaid for poor tuning than a safety net. I've seen motors blow up from detonation even with those things. Honestly, sell it, and put the money elsewhere is the best advice I can give you, b/c it won't save you, and it's even worse with forged pistons.

GruvyTune

well, i'm getting max power at A:F ratios of about 12.9:1. a little lean but no signs of detonation. perhaps the 9:1 pistons are helping with that. I like the idea of the safeguard and I don't look at it as a bandaid. my tuning is dead on and I see it as a backup precaution for all the hard work tuning and building my engine. I'm just trying to see if there is an effective way to make sure its working. however, i'm beginning to believe there is no real way to be sure its really protecting me from anything!

thanks.