Optimal Spark Plug for Cat (Suzuki) 800

[Frostbite]

I am going to buy a couple more sets of spark plugs for my Proclimb and M8. I notice on my M8 at some point I switched from BR9EYA over to NGK BR8EIX Iridium plugs. I remember reading at some point that they were less prone to fouling. I hunted both forums (Proclimb and M Series) for a post that would have pointed me that direction and can't find one. I know I have had great luck with BR8EIX plugs but, before I buy some more I thought I would ask what what plugs you guys might be running other than the manual specified BR9EYA plugs?

Also, I saw a post on the M series forum that suggested using Autolite XS4063 Xtreme Sport Iridium Enhanced Spark Plug. The poster "Clutchweight" claims:

"I've been running Autolites for a few years now. The XS 4062 is equivalent to NGK BR9's. They produce 2.5 to 3 HP more than a BR9ES or and EYA. They are hard to read without cutting the thread off and looking for the ring on the porcelain. Many racers use them".

I haven't tried them, has anyone else?

 

[Phizzer]

I have a hard time believing a HP gain by switching to a different plug without seeing some actual data. A more efficient and clean burn could lead to HP increase I suppose, but there are so many variables. I've never tried the Autolites...Always stuck with the NGK's. Be interesting to see if there was an actual improvement though.

 

[drummerdave]

The only way a spark plug (of the same heat range) can cause an increase of HP is if the old ones are bad (or poorly gapped) and not firing.

 

[Frostbite]

That's exactly what I thought!

I was hoping one of the Wizards of Smart might know a thing or two about what plugs might be the best.

 

[Dam Dave]

Stock, I haven't carried a spare slug since about 2008

 

[RACINSTATION]

BR9EYA

 

[Vern]

Used the br9eya on m7, rode it for 8 years and probably only changed plugs in it 3-4 times. And those times were just because I figured it was due, never once fouled a plug on it and it was a carb'd sled.

 

[89sandman]

BR9EYA, you can gain 20 hp if you click your hills together and say "to the snow I go" when you put them in

 

[kiliki]

BR9EYA

^^^ if your luck you will foul one.

 

[Frostbite]

Here are the two plugs NGK lists for the M8 and M8000.

This is from NGKs website:

BR9EYA (7548) as the standard:

http://accessngk.com/part_finder/Snowmobiles/results.asp?id=234&type=std

If buying 4, the cheapest on Ebay is $11.35 with free shipping.

http://www.ebay.com/itm/NEW-Set-of-...ash=item2337a41c40:g:4PMAAOxy~dNTKJk2&vxp=mtr

BR9EIX (3089) as the Iridium:

http://accessngk.com/part_finder/Snowmobiles/results.asp?id=234&type=ir

If buying 4, the cheapest on Ebay is $20 with $4.00 shipping or $25.84 with free shipping.

http://www.ebay.com/itm/4-X-New-NGK...ash=item51c6f9f4df:g:0UYAAOSwjVVV5Yj5&vxp=mtr

It looks like both plugs use a .031" plug gap.

Maybe this is where I found the BR9EIX number.........If the iridiums are longer lasting, they may be well worth the $3.16 more per plug?

 

[Vern]

Simple copper plugs conduct better. I'm a gm guy and one of the first and cheapest "performance" mods recommended in the gm gasser world is ditching the factry iridiums for cheap copper plugs, dont see why it would be any different in a 2 stroker

 

[Frostbite]

Really......wow Vern, I have never heard that one before. Good to know.


Does anyone "index" their plugs anymore? That is when you line up the opening between the electrode and the part you gap toward the intake). That was a big thing in the 90s but, I don't hear much about it anymore.

 

[Vern]

Really......wow Vern, I have never heard that one before. Good to know. .

at least on the 8.1l anywho.

 

[kiliki]

frosty you need to take a deep breath. now embrace technology, none of the makers have the plug problem we had 10 years ago. aka EFI, higher ignition systems and less dino oil.

 

[XtremeSpeedShop]

Never had a issues with Br9eya, I've tried about every type of plug on my dyno and usually an old plug or incorrect heat range is the only thing that will make a huge effect on power output imo

 

[Frostbite]

Good to know, thank you xtrememotorworks!

 

[05M7]

I tried the BR9EIX on a few different ocasions. Always ended up going back to the BR9EYA

 

[CATSLEDMAN1]

SPARK'N FOR PERFORMANCE

the electrical ignition systems of the last 20 years using a brain box /black box /ecu etc etc, have often been designed to work with specific spark plug resistance.

so when the auto supply store says we don't have your plug anymore we have iradium what evers, don't buy that.
The vast majority of Chevy and Dodge pickups, Subaru's, Toyota that I am familiar with will run best and sometimes only run at all with the original plugs. Plugs at twice or three times the $$ are not higher performance or same as plugs.

Most noticeable on M6 recently, poor low speed running........some bog, oem new original plugs, way improved idle and low speed bog gone. Same experience with 2002 Rav 4 a month ago, whoop *** iradium plug poor idle, std called for plug from Toyota, acted like a new car..............smooth idle and wanted to pick rpm.

 

[Empire087]

Br9eya, nuff said. Oh ill note that the autolites are junk, ran a free set to try them and they ran like crap. Switched back to br9eya and run them in literately every 2 stroke application they fit.

 

[Rush600guy]

Br9eya is a plug that cleans itself due to more surface area with a v notch. That is why so many people havent changed a plug in a while.