Hey guys, Does anyone know what heat range LFR6A-11 is for an evo 9?

-Steve

 

Those spark plugs are OEM for a Yamaha F115 outboard

 

They were garbage in my car. I went back to IKH24 Denso. Next try will be IKH27


S

 

I first got them from MASTER BUSCHUR

 

They are hotter then stock and will not fire properly.

 

This what NGK told me. "The LFR6A-11 is indeed one heat range hotter and will NOT burn colder
than the stock ILFR7H. The other problem is that the set gap of the
LFR6A-11 is at .044" (1.1mm) which is too large for this application and
will not fire correctly if gapped down to .030", as the gap should not
be changed more than .008" from where it is factory set.

To go colder we currently only offer iridium race plugs which are part
numbers R7437-8 (projected tip, street use) or the non-projected, fine
wire, low angle ground electrode version R7438-8 (race use only or high
boost, may foul on street) Hope this helps clear things up. Thank you.

Best regards,



Brandon Peeler

Technical Support Representative

 

do the R7437-8 come pre-gapped?

 

these plug work well on the 9, i've used them before. Buschur has used them numerous times

 

...

 

anymore info on these plugs or if there are colder ones available?

 

BR8EIX is one step colder Iridium, and BR8ES is one step colder and standard. I am going to try the BR8EIX on my new build since buschur said Iridiums cleaned up the dyno graph on his Project White on the stock ignition.

 

^ This thread is about the copper variations, LFR6A-11, for the Evo9. Evo8 and 9 plugs are not interchangeable!

 

well 800hp on them is too much but DG have used them up to 650hp on IX's ...https://www.evolutionm.net/forums/7377421-post129.html why don't you call them out as well as Dave Buschur as far as gapping more than .008 there might be an issue with some plugs but I gapped mine to .022 and it works just fine