Dyno. What's another $100 when you've spent so much already. [img]i/expressions/face-icon-small-smile.gif[/img]

 

my brother is running a Pro Circuit T4 pipe, i'm the one running the mbrp slipon, we both have dj kits, by what i've read on here it seems like hes rich, but his plug is a lot lighter than mine, but maybe i'm just really rich since i've got a 180dj with my wonderful mbrp pipe, lol

 

It's not a matter of $$$ its finding someone who knows how to do Quads.......[img]i/expressions/face-icon-small-mad.gif[/img]

 

I have dynoed an MBRP slip on and it performed pretty good.

A stock DS idles at about 10:1 A/F ratio on the dyno.

 

holy, your the first person in a long time that doesn't bad mouth the MBRP pipe, btw which one did you dyno, std or race? and do you still have this dyno chart around somewhere?

 

Eric,

>>very rich engine will stop the exhaust from glowing

If 10:1 causes glowing, what do you consider very rich. At 10:1, I would of thought the bike would be hard to start and that factories jet lean (15:1) at idle for easy starting.

>>There is a hot side of lean and a cold side.

I've always considered the bounds to be 14.2 - 13.5. What do you consider these bounds to be? Your statement about the 10:1 setting infers it is within your bounds since it is still glowing.

jbt

 

Under full power 10:1 is very rich but at idle its not that big a deal to be running 10:1 or 11:1. Idle conditions and full power conditions are totally different. At idle there has to be a certain amount of extra energy (heat) in the cylinder to keep the engine running. If you get a blow torch set for optimum heat and it goes out can you relight it with that setting? No, you have to start with lots of gas and increase oxygen a little at a time.

I used the hot and cold side of lean info to make a point that not many people have thought about it in that way. In other words there can be a cold side of lean.


Different engine combo's call for different A/F ratio's. I have seen peak power come in anywhere between 12:1 and 14:1. There is not an ideal A/F ration that everyone should shoot for.

If I'm not mistaken modern fuel injected cars and trucks run in the 16:1 to 17:1 range for fuel economy. They are probably running on the cold side of lean. This is why they hold together for 200,000 miles because there is no fuel wash in the cylinder.

 

An exhaust valve that isn't closing all of the way will cause the pipe to glow red on a 4-stroke.