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WydRyd WydRyd is offline
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Join Date: Mar 2002
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Hi Les. I think we're on our own here. All I can suggest is regapping it as large as you can without any misfiring under heavy/max load at your max boost setting. So, if you're spark output is reliable and consistent at max boost of Xpsi, then try opening it up a little until it misfires, and then drop it down a notch until it's firing reliably again. That's all I can suggest. At this stage, it's really just trial and error, since no-one here has really gone down this path it seems

As usual, each motor is different, so what may work in mine, may not work in yours.

I'm currently running 0.035" in mine and at ~1.15bar, I think I have misfiring/missing under heavy load in the higher gears. I'll try dropping this down to 0.032" and try it out for a week or so. If that fails, then 0.030", then 0.029", etc...

The idea is to run the largest gap you can whilst maintaining reliable ignition at max load. This will ensure optimum ignition of the A/F mixture and best economy etc...

Then again, the word "economy" goes out the window in heavily modified cars like ours

P.S: The gap will also depend on the type of plugs you're running. e.g: platinum plugs are easier to fire than silver plugs, so you may be able to run a larger gap with those. Lots of factors come into play here, even the type of ignition system you use, such as CDI, or wasted spark etc...
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition

Last edited by WydRyd; 04-05-2007 at 06:39 PM..
Old 04-05-2007, 06:35 PM
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