My CenterForce feels almost exactly the same as the OE clutch, certainly not heavier, just a little more positive on the initial pickup. Also it shows up on down shifts, the OE clutch had just a slight delay in the revs sinking to the new engine speed after changing down, the centerforce is almost immediate, strange, but true. No chatter, I would say it's actually smoother and more driveable than the OE. Most reports on the Miatapower list, even where criticism of it's power handling has been made praise its drivability.

The J&S at present is on a very low sensitivity setting just above 9 o'clock, it takes out timing after the first 2 to 3 pings. This setting is well below the instructions "turn it down until the engine stops bogging", when I did this it still picked up road noise and retarded (still does very rarely, just when lightly accelerating after start up or in rain and edging into boost). Basically if you hear it ping and the J&S doesn't retard, come straight off the gas, stop and turn up the sensitivity. It's likely to cause serious damage to the engine if you allow it to continue detonating (but you know that anyway). I found setting it up quite simple to be honest, got it on first try, some have found it less so Dual display helped a *LOT*. Do you have the display (dual or otherwise)? I would say that setting up the J&S would be near impossible without it (or very difficult) + it only retards 20 degrees max and you need the display to see what it's doing. The Fuel ratio is also very useful for fine tuning an AFPR. IMO J&S should really emphasise the need for the display. In the US it's not so bad, people can often borrow them for initial set up and save the $150.

I found setting it up quite simple to be honest, got it on first try, some have found it less so, Dual display helped a *LOT*. I'm using 'retard individual'. (12/99)

This subject has my head inside out at the moment. Anyway, basically I went for the Max5 clutch from Performance Buyers. It will handle way more torque than I will be putting down, so my sloppy driving style shouldn't hurt it too much. I'll let you know when it's in what it's like. Once that's sorted I'll set the timing and the J&S and then it should be Dyno time! Hurrah!

As for the J&S, I don't have the display, but I think that I'll get one. The reason I asked about the cylinder setting is that I have had some discussions with people about this and they say that it can get the cylinders wrong sometimes. Now I have no way of knowing if this is true, but I have no idea of how it tell which cylinder is knocking with only one mic. The other tip I heard was to set the sensitivity low and then retard timing, or reduce boost, so that it is only just cutting in at max boost. Reason being that you retarding timing across the board is better for the driveability than to have it retarding 20 or so degrees just when you don't want it to. Anyway, this is all rumor at the moment since I have a clutch made of rubber until this new one turns up. (12/99)

I would guess the J&S knows which cylinder made the 'ping' because it intercepts the cam-angle sensor signal to the ECU. I may be wrong!

Setting the timing to just below pinging is something which has been discussed on the Miatapower list. The J&S takes out an extra 4 degrees than necessary when it hears ping due to the increased temps it causes, causing the engine to ping more easily (feed back effect). If it hears no further pings after 20 engine cycles, it then lets timing back in gradually. I've noticed this, the J&S will actively retard from 3500 to 5000 rpm, then lets it go so that by 6000 rpm its occasionally not retarding at all. Whether there are power gains to be had by setting timing to just below the ping point is questionable. You'll lose power throughout the engine rpm range where the timing could be more advanced without ping to get rid of ping and gain some power in the mid-ranges (most prone area). Even with the FM ECU (more elegant solution) the timing has to be retarded here to prevent ping (although if done right it'll save that extra 4 degrees that the J&S takes out = more power). IMO I think better power overall will be had throughout the range by letting the J&S do its job, but keeping the amount of retard down to a sensible value. J&S have a web site at www.safeguard.bizland.com

My timing is only set to 8deg at the moment so I'm not getting any detonation, once I get the clutch sorted I plan to bump it up to 12 then 14deg. What's your J&S set to 'retard all' or 'retard individual' and what sort of sensitivity have you got it set to?

Don't go higher than 10 or 12 degrees, otherwise you will lose power from the J&S taking out too much timing. (12/99)