Running rich? on CR10EK's

[yammi]

Anyone experience a rich condition with the Cr10's for plugs? Sled seems to run fine, better actually with the new plugs, but my buddy and even me from time to time, seem to smell a sort of unburnt fuel smell since the plug change. Other things done at the time of the change were oil, filter, carb clean and carb sync. Like I said, runs great, idles perfect now thanks to clean pilots and carb sync and actually pulls harder than ever. Just wondering if anyone has experienced this before? Thanks

 

[RedRocket]

Why did you go to a higher heat range plug with no fuel modifications? The stock plugs are NGK CR9E and check the gap, it should be between 0.7-0.8mm (0.028-0.031 in). If the plug gap is too high, there is a slight chance that the spark actually gets blown out and does not combust fully which leads to unburnt fuel. This is usually only found in high compression turbo/supercharged engines but it possible.

 

[LazyBastard]

Its actually a colder plug. He went with it because everybody on this site told him that it would make 3-4 hp more by just changing the plug. This is apparently proven.

However, since its a colder plug, it won't fire as reliably, particularly at low speeds and when its really cold out. This can lead to unburnt fuel being dumped out the exhaust, HOWEVER, I tend to believe that its more likely something to do with his "carb clean and carb sync".

 

[RedRocket]

Its actually a colder plug.

Who said it was a hotter plug?

I said "higher heat range", in other words it can dissipate heat faster which in turn makes it a colder plug. Next time I'll try not to use big words...

Change the damn plugs

 

[LazyBastard]

If thats what you mean, then thats what you should say. Don't use ambiguous phrases. Depending on who you ask, that phrase can mean EITHER.

Whether a spark plug is "hot" or "cold" is known as the heat range of the spark plug

The measure of a spark plug's ability to dissipate heat from its firing end. The higher the heat range, the hotter the plug fires.

The degree to which a spark plug disperses the heat it receives is called its "heat range".

 

[yammi]

Its actually a colder plug. He went with it because everybody on this site told him that it would make 3-4 hp more by just changing the plug. This is apparently proven.

However, since its a colder plug, it won't fire as reliably, particularly at low speeds and when its really cold out. This can lead to unburnt fuel being dumped out the exhaust, HOWEVER, I tend to believe that its more likely something to do with his "carb clean and carb sync".

LB, that's why I mentioned the changes done at the time of the plug change. Thanks. Unfortunately I don't have the liberty "time" to make changes one at a time to realistically test each and every option that you guys are so graciously willing to help out with. So instead I do what I need to do, unfortunately with the help of my buddy/mechanic in combination with your (site) help and when the conditions afford for testing, and go from there.
I didn't mention the change from Klotz to Amsoil snow specific oil because I didn't think it appropriate. I even thought an overfill oil condition/airbox issue, but I was even so anal as to .5 qt engine, 2.5 qt reservoir and then add from there! Just wondering Thanks again . . . .

 

[yammi]

!!!

BTW, I know it's a colder plug. Common misconception, pretty funny eh!
Sync, clean pilots, bowls, etc, sync, again thanks to supertuner! all good stuff, emoticon free, this site rocks!

 

[LazyBastard]

Yeah, oil and overfilling oil is not much of an issue on these. If you put in so much that it blew into the airbox, then I could see it causing an issue, but being dry sump, the amount of oil thats actually in the engine will level out immediately.

 

[yammi]

yup, 3 qts on change, 4th to dial, fill accordingly! I figured that, oil not an issue, we'll see. Not too worried, just wondering, runs like a bat out of hell, specially with the Boivin transfer, gotta love it!

 

[Mikey]

yammi are you running the complete ECP kit with these plugs or just the plugs alone?

 

[yammi]

stock airbox

 

[Mikey]

If I remember correctly there was no gain to be found with just the stock airbox. The gain was found when those plugs were used with the complete ECP kit. Filters, springs, and jets.

 

[yammi]

Maybe it was all in my mind then - better throttle response, pulled harder. Either that or the clean and synced carbs may have done it. Other than the occasional smell, it runs great. I guess I'll leave them in for now, replacement, who knows. Either way, no one has heard of this happening, the smell that is?

 

[outlawrx1]

what plug is it and what other adjustments for 3-4 free h.p.?

 

[LazyBastard]

It has nothing at all to do with airbox modification. Colder plugs just make more power. Nothing else changed. Side-effect is that they're easier to foul.