fuelman8

What's the plug gap on an NGK CMR7H in a SIKK 25.4?

Thanks

SUPER-V

.22 - .25 is typical , at least for the Zenoah engines.

cheesewizz69

I lost 2mph at .22 when I gapped back to .25 I picked up the lost mph.

Stock EZ25 from WHH (260PUM) with canister exhaust.

fuelman8

Thanks Super & Cheese [8D]

monsterbrad

That is very interesting that .25 to .22 will make that much difference.
hmm

cheesewizz69

What can I say? I ran it 15min apart with the same GPS that has given me consistent speeds (+/- .3 mph). The wind/water conditions did not change. Ooh and with the same plug only change was the gap size. Like everything in this hobby each engine/boat will respond differently.

PS To anyone reading this please do not start a thread war on GPS vs whatever. It is what I use and I like it.

wet a wild

i run same plug and motor and the best so far for me .7mm plug gap

Jamming

I posted somewhere else and never got a answer, So i purchased 3 iridium plugs at $14.95 each and the some*****es wont fit under any of my hatches, there a little longer than the champion plugs that are stock. What and where can i buy the NGK plugs. Model number please. Thought about using a hole saw, But man that would suck having a plug cap sticking out. Besides water can enter.

t00fatt

Me and cheesewizz picked some up from a big advanced auto parts yesterday, it was the main warehouse one though so you may have to order them at the regular stores. But they were only $3.99 a piece instead of $8 or $10 at the LHS.

cheesewizz69

Take a trip to your local auto parts store's distribution warehouse. Ask them for NGK's CMR7H $3.99 each. If you have an Advanced Auto Parts in your area ask for part number 3066. Most of the Autozones, Advanced Auto etc... wont have them at the smaller stores but they can get them for you if your willing to wait.

Jamming

Thank You !!!!!

Jamming

Nice ! Found them at Napa $3.77 each, Anyone wanna buy some iridium plugs. LOL !

SUPER-V

I tried the NGK irridium plug with negative results .

Jamming

Yea me too, I bought three of them and they dont fit. To long !

Bbbutch

Just tested different plug gaps this weekend on a modified Zen 26, NGK CMR7H in a 51" mono. I tried .22 to .30 and used a GPS along with my eyes and ears for rating each gap.

.22 I also lost 2 MPH from what I ran at .24
.23 Was the same as .22
Throttle responce was very hessitant at .22 and .23
.24 Ran well and back up to speed.
.25 Ran well
Slight throttle hessitation coming out of the corners at .24 and .25
.26 Ran well and no throttle hessitation at any time. (My new gap)
.28 Ran well but speed dropped 1 MPH.
.30 Ran well but speed dropped another.5 MPH.

As someone else has stated every motor ans setup is different. These are the results I got from mine.