miro_gt

Turbo D16Z6, with intercooled Greddy 15G, running 9psi with the stock injectors I've got 6" JRC intercooler.

I get temperatures in the range of 70F - 130F, and that's at 50 deg F weather temperature .. I let the car idle for 20 min, and the IAT went up to 160 F

So for the compensation, I did -1% fuel for every 10 deg F increase of the IAT. Ignition compensation starts after 140F, where it's like -3 degrees.

what do you guys have for the fuel ?

0xenocron

What engine management system are you using?

igo4bmx

he is using s300
now im curious what the neptune guys do, if it differs

miro_gt

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xenocron &raquo;</TD></TR><TR><TD CLASS="quote">What engine management system are you using?</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by igo4bmx &raquo;</TD></TR><TR><TD CLASS="quote">he is using s300
now im curious what the neptune guys do, if it differs</TD></TR></TABLE>

yep

0xenocron

Well...I dont know about S300, but within Crome, the values are stock and this is generally fine because the IAT Timing Compensation maps should not need to change unless you move your IAT sensor from your Intake manifold to your charge piping. The IAT fuel compensations with stock settings will always be richer if you are moving to larger injectors so generally you want to decrease these numbers slightly depending on which injectors and what size they are.

I know Neptune has safe 'base' numbers in there (probably close to stock)...but whether you are using Hondata, Neptune, Crome or other...you really need to do some serious calculations and use a wideband although it is extremely hard to keep intake temps controlled well.

It all comes down to how each system uses these numbers in its calculations, the injector brand and size you are using.

igo4bmx

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xenocron &raquo;</TD></TR><TR><TD CLASS="quote">Well...I dont know about S300, but within Crome, the values are stock and this is generally fine because the IAT Timing Compensation maps should not need to change unless you move your IAT sensor from your Intake manifold to your charge piping. The IAT fuel compensations with stock settings will always be richer if you are moving to larger injectors so generally you want to decrease these numbers slightly depending on which injectors and what size they are.

I know Neptune has safe 'base' numbers in there (probably close to stock)...but whether you are using Hondata, Neptune, Crome or other...you really need to do some serious calculations and use a wideband although it is extremely hard to keep intake temps controlled well.

It all comes down to how each system uses these numbers in its calculations, the injector brand and size you are using.</TD></TR></TABLE>

very good point- I guess when you add 1% more fuel from 1000cc vs 1% from 450's it really does make a difference

miro_gt

well, I'm gonna put it this way then:

when I add 1% fuel, my AF enriches with 0.1:1 AF ... or 10% more fuel will increase the AF with 1 point. That's with the stock injectors, but I'm gonna use the same with my RC440s as well

so can anyone post numbers for their compensation, and I guess specify the injector size then ?

again, I did -1% fuel for every 10 deg F increase of the IATs, which means that for every 10 deg F IAT increase, I've leaned the mixture with 0.1:1 A/F

miro_gt

anyone ?

D@nnY

the s300 compensation doesnt work correctly....and the size of the injectors wont make a big difference with the way the program works about 9 percent will be 1 point difference in air fuel

miro_gt

^ that's what my car does. 1% fuel increase changes the A/F with 0.1

I've heard about the problems with the compensation of the s300 ... but I tend to think that higher values work somewhat. At least, that's what a couple of people said some time ago ... but I haven't tried higher values, that's why i wanted some opinions

.dave

I use a GM IAT sensor with my S300. From what I've gathered from discussions with several people on here, the stock Honda sensor doesn't respond fast enough.

miro_gt

^ I've never thought about that, but I guess it's true. It does take a few seconds for my s300 to sense the IAT

0xenocron

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .dave &raquo;</TD></TR><TR><TD CLASS="quote">I use a GM IAT sensor with my S300. From what I've gathered from discussions with several people on here, the stock Honda sensor doesn't respond fast enough.</TD></TR></TABLE>

This is true if the sensor is in the intake manifold like most...if you retrofit it into the charge piping the response is faster. Not lightning mind you, but faster...

Couple posts by 'Blundar' in some threads in the FI section are a little better explained...

raene

If they're stock injectors, I would keep the IAT compensation stock... I tend to scale the IAT and ECT by the size of the injector compared to stock.

miro_gt

I've installed my RC440s already. And the IAT compensation is still -1% for every 10 deg. F increase of the IAT. Looks like it works very good.

I had to adjust the ECT compensation as well, but that was no biggy