What to do about spark blowout?

**Spinnetti** · 05-17-2008 07:51 PM

Have BT from eurocode, Timing 6, boost 9, and tried various fueling, currently maxed out. It doesn't pull any CF, but on anything but a cool or wet day, I get what appears to be spark blow out (not knock) above 4500rpm. Some days I get it, some I don't. Note that it doesn't happen at full load at other rpm, just above 4500 or so. I put a fresh set of coil packs in, but it didn't change anything. I'm running the side electrode plugs that came with the turbo.

Ideas? just too much boost without meth? I wonder if some Iridiums a couple steps colder than stock would do the trick? (I sure wish there was better ignition solutions available).

I tried lowering the timing, but hate how it runs on anything but 6, and it still does it. Lower boost works ok, but what's the fun in that....

**F16HTON** · 05-17-2008 08:04 PM

Change the gap to .029 and see if it helps. Are the plugs the Bosch FR5-DTC? You need to change them every three months or 3,000 miles for optimum performance.

**diagnosticator** · 05-18-2008 12:50 AM

Less boost and more timing advance, if properly ballanced, should provide about the same torque that you are realizing now, without the spark blow out experienced with the boost and timing settings you use currently. 034 EFI's website has high output ignition setup available.

**A4TL** · 05-18-2008 03:56 AM

if your air fuel ratio drops below 11.5:1 you will probably see blowout. Unless you are talking high rpm's which would be odd you shouldn't be running richer than that unless you are huffing phunny gas.

usually the rich misfire is just from poor tuning too rich but of course your wideband would tell you that (along with whacky EGT's to back it up).

gap and "R" coilpacks for sure. Too cold of plugs maybe but i run BKR7E on my stage 1+ all winter long without a misfire.

**MikTip** · 05-18-2008 04:03 AM

Have you tried the Bosch F5DPOR...

**dirtybrd** · 05-18-2008 08:03 AM

FR5DTC's fixed it for me, I had aproblem with it a long time ago. I was having some random misfires but strangely they went away after I put the cams in.