jerseydevil

I'm looking for info on how each cylinder mixture is affected by engine design. I"m got a set of injectors cleaned and they'll be arriving soon. I have the data on each injector's flow rate and wanted to put each in the right spot on the intake manifold based on air flow into each cylinder. Assume stock engine, b18c1. I thought I head read a thread about this on here some time ago, but i can't find it again.

If memory serves me, number one cylinder runs richer than 2/3 due to intake manifold design. It "sees" less air flow as the precedding cylinders "steal" it to keep things in simple terms. The same goes for cylinder #4, as there's a low pressure area near that runner due to intake air velocity causing air to pass over that runner.

Is that right? I know we're talking about subtle differences in air flow, but the differences betten the injectors coming back are subtle as well.. 1-2mL differneces. But since the injectors are being swapped, might as well tryto match things up as best as possible.

Anyone have some real info/data regarding this?

6SPD_EK

iTrader: (2)

cylinder #3 typically runs the hottest so you want the most fuel in it - then #2

the best way to measure is by using 4 egt (exhaust gas temperatures) sensors on each of the primaries of the header

I don't know for sure if injector flow rates will do much to get more fuel in the cylinder unless you are running 100% duty

some engine management allows for fuel trim for each cylinder - I know Hondata K-pro does

Padawan

Interesting concept. As you stated, the difference in airflow as well as the difference in injector fuel flow will be very minor. You're probably on the right track as far as the theory is concerned, but the only 100% conclusive method of confirming the information would be to install an O2 bung in each of the exhaust primaries.

6SPD_EK

iTrader: (2)

egt's are thermo not o2

and you tell by the temperature of the exhaust gasses how hot the cylinders run & the variance between the 4 of the them

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 6SPD_EK &raquo;</TD></TR><TR><TD CLASS="quote">egt's are thermo not o2 </TD></TR></TABLE>

Yes, I'm aware of that. I was responding to the original poster. Individual lambda sensors would accomplish the same thing as the EGT's, and there would not be any interpretation of temperatures involved.

jerseydevil

Thanks for the replies guys. Given the minuet differneces we're talkinga bout bettwen injector flow and air flow, I don't think it's worth the trouble to put in four sensors to monitor the invdividual mixtures. Would make for an interesting project and learn some theory but it's just not in the budget, not now anyway. I'll put the highest flow into cylinger 3 as mentioned, then 2.. Even if that turns out to be wrong in theory, it couldn't be any worse off than random placement.