I am not sure how much it has to do with the HI-6 ... but I assume that it has somthing to do with it.

When I did my rebuild I had two brand new sets of plugs, one set of NGK'S and one set of Nippon Denso's. I was swapping them in and out for the first couple of days to fix new engine flooding issues. I got it running with the NGK's everything was fine, I installed the Denso's and my HI-6 at the same time, eveything was fine. just the other day I pulled my plugs again, they were a little cruddy so I went and got a brand new set of NGK's... popped them in and it hessitated like **** above about 3k RPM's.

So I though hmm ... maybe I got a bad plug or somthing .. so I put in my old original set of NGK's (maybee 600 miles on them) same damn thing .. so back to another parts store I trek, this place carries Nippon Denso's I got them instead.. and Boom! hessitation was gone!

My conclusion; the NGK's have a cut-cross format to them ... with gaps seperating the 4 sections of the plugs .. the Denso's are solid all the way around, I *think in my own head* maybe the extra juice of the HI-6 is causing some kind of negative arching across the slits in the NGK plugs ... thats the only thing I can think of. The HI-6 fires one solid spake (as opposed to multi spark) above 3k RPM's and thats right where the bad hessitaion was kicking in with the new NGK's installed.

Just a theroy .. but for future consideration if anyone does this upgrade and has any issues .. try Denso plugs.


And before anyone says anything stupid; I did have trailing and leading correct, I did have the right NGK plugs .. 7L 9T.

 

hmm my NGK's and crane hi 6 are fine

 

Yeah, mine too. HI-6 works flawless for me. CJ

 

How do you guys have the cylinder select wire wired? I was wondering about that maybe being a issue. 2 different sites I looked at said to wire it 2 different ways.

to hot = 4 cylinder mode
to ground = 6 cylinder mode
not hooked up at all = 8 cylinder mode


I have mine wires in 4 cylinder mode, either Ted's or Fc3s.org's site said to do it that way .. I can't remeber what said what ... I thought maybe that was the issue.

 

denzo plugs are crap.. They caused alot of problems in the RX7s I have seen them in.


NGK is the best plug out there

 

mines at 4 cly. but I had it at 8 for the first few weeks. didn't notice any diff when I changed it.

 

1) Flooding CAN kill spark plugs.&nbsp If you don't believe me, let your spark plugs soak in a can of gasoline - the gas kills the electrode.&nbsp To test, I measure resistance from the spark plug wire end to the center electrode - they should measure between 2k to 1k ohms.&nbsp New NGK spark plugs typically measure around 1.7k ohms; "worn" NGK's wear down to about 1.0kohms - yes, the resistance goes DOWN, since the electrode is shorted.

2) Set the "cylinder" select to 4-cylinder, since your leading spark plug fires one spark per RPM revolution.&nbsp This is what a 4-cylinder motor does, so you're just matching the ignition sequence type.&nbsp A V8 fires one spark every other revolution, so if you set it at V8 mode, the HI-6 will think the engine is running two times as fast [think about this hard now, since it's not exactly straight-forward ] (versus RPM reference).&nbsp This cylinder select only really affects 1) the 3,000RPM crossover for the multi-spark mode (if you have this in effect), and the rev limiter (which the HI-6) can't fully engage properly in this particular installation application.



-Ted

 

The only bad poin tI have found with Hi6 and LX92 (one per leading plug) is that there is soooo much "juice" being thrown out that it wears the plugs out super fast !

That is the price you pay for a strong ignition system i suppose

I have herd of guys having multiple problems with NGK's but they are rare, though have been known to happen, you should try and switch over to the B9EGV or B10EGV plug they do run smoother than the BUR plugs, though you may find they do not last as long ? I would not know I never use the factory plugs as I have never liked the way they run in any turbo engines I have tuned or owned.