Important note for hi comp users

[francky2000]

Hi,

I was asking in another topic if the increase of comp required the use of a different spak plug.
So I contacted NGK and ask the same question...the answer is yes.
Quote:
Hello,

With that high of an increase in compression I'd suggest starting with a two heat range colder plug part no. CR10E stock# 6264 or for better performance the iridium plug no. CR10EIX stock# 6482 Hope this helps, thank you.

Regards,

http://ngk.com/results_cross.asp?pid=cr10e

http://ngk.com/results_cross.asp?pid=cr10eix



Brandon Peeler

Technical Support Representative

Aftermarket Division

NGK Spark Plugs (U.S.A.), INC.

46929 Magellan Dr.

Wixom, MI 48393

http://my.artoffast.com/NGKTECH


-----Original Message-----
From: franck_j@hotmail.com [mailto:franck_j@hotmail.com]
Sent: Wednesday, December 16, 2009 11:59 AM
To: Info
Subject: [Tagged as Possible Spam] NGK Form Mail
Importance: Low

**** Contact Form & Tech Info Feedback ****

Email From: franck_j@hotmail.com
VehicleType: ATV
Make: Yamaha
Model: Raptor 700R
Year: 2008
Engine Type: 700
Comments:
Hi,

I am racing with my ATV and currently going through some modifications on the engine. The stroke and the compression ration have been increased.
Stock was 9.2:1 now it is at 11.7:1
The stock plug is a CR8E.
Since the compression ration is increased and the use is exclusively race (With road gas only) is it necessary to change the spark plug  to a cooler type?
Thank you very much for your support.

Regards,
unquote.

The spark plug have an important role in the evacuation of the heat in the combustion chamber. Some road bikes are running stock with 12.8 compression ration and can use road gas. what allows this is the plug.

[Peelz]

that guy must be smart...look at his last name. 




good info francky

[VelociRaptor]

Well, theres been tons and tons of guys(including myself) run the stock plug with 12:1 or more compression. When I built my first 700 back in 06 I went to a 9 plug and it stumbled and had not as snappy throttle response compared to the stock 8 so I went back to it. This was also back in the day when you didnt have a way to adjust the timing, just the fuel curve. Ive built and tuned engines since then and still run the 8 plug.
I do agree with what they have to say(since it was in the same line of thought when I swapped my plug back in 06) but the 8 plug runs so good its hard to go to anything different.

[preddy08]

I've been running 14.25 compression, the stock plug, and a Dyna with DL700's timing table for 2+ years. I've had ZERO problems thus far.

[RaptorRandy]

I ran the  CR9EIX in my 780 when tuned for max HP & TQ.......never gave me any problems and ran quite well 

[Troy]

I just dyno tested a plug tonight that netted me 1 horsepower at peak and two horsepower from 8200 to 9000.  No plug wire mods or anything else, just sparkplug.     For info, send 20 dollars to troywcc@hotmail.com

[Peelz]

I just dyno tested a plug tonight that netted me 1 horsepower at peak and two horsepower from 8200 to 9000.  No plug wire mods or anything else, just sparkplug.     For info, send 20 dollars to troywcc@hotmail.com

done.

I should be close to 90 now.

[Tim Barker]

I just dyno tested a plug tonight that netted me 1 horsepower at peak and two horsepower from 8200 to 9000.  No plug wire mods or anything else, just sparkplug.     For info, send 20 dollars to troywcc@hotmail.com

What was it a new one

[Tim Barker]

I have always ran as hot of a plug that i can get away with and not have the engine pre-ignite.