Newbie Help To Map Apexi Fc

[nissan200sx.dk]

Hi there.

Got the Fc datalogit, laptop, LM1 hooked up to fc datalogit, and a apexi power FC.

Now I need to know how the Af should be..

Could someone rougfly point out what AF ratio I should aim for, layed out on the 20 x 20 inj map. Not each map point, just say the first 5 x 5 should be around XX, then up to 10 x 10 it should be around XX..

Thanks.

Best Regards

Ronni

[The Mafia]

the first 10 rows should be aiming at about 14.8:1

After that, I'd start richening up the mixture row by row until you can get the last line the car uses to run about 12:1.

I'll get a picture and show you in a sec

[Guilt-Toy]

it all depends on the engine and setup that your running.

some cars need to run a little richer to run correctly on lower load points.

I find that some cars can run fine at 14.7 on cruise across the whole board but some cars will run like a dog and will need to be richen'ed up to around 13.6...

For AFR on boost it also depends on how modified the car is. If you have a stockish car then 12 afr is fine... if your pushing alot of power then its good to run it in the low 11's to keep the engine cool.

[The Mafia]

run it in the low 11's to keep the engine cool.

I disagree with that statement.

I'd still run a flat 12:1, as any lower starts to rob you of power an is just rumming the engine too rich. If the car is overheating, then there is something wrong with the Coolant system.

I'm running 13:1 afrs with water methanol injection. Engine sits at about 79 degrees after a few hard runs.

I'd only go richer if its pinging and taking timing out doesn't stop it in that area, but I have never come across this so I don't you should either.

this is what I run without WMI as promised:

[Guilt-Toy]

Why do people allways run their cars on the edge to get max power at the expense of reliablility ?

Running a engine hard on .85's can work yes. But what if there is a bad batch of fuel in the question ? or a fuel pump starts to fail a little or a fuel reg does something silly it could change the afrs to .87 .88's on a highly tuned engine after a short time you will have a broken engine.

I like to see mine running at .80's and .82's when im pushin 25psi and 360rkw.. sure i could bag a extra 20kw if i leaned it off but i ike my engine and i want it to last.

More power is not allways better.. reliability is where its at as far as i am concerned

If you have a really good quality fuel system and EGT's in each cyl to make sure every cyl is getting the exact amount of air and fuel as each other and you are 100% sure everything is working correctly then sure run it lean...

Using water changes everything and you can run it leaner.

I disagree with that statement.

I'd still run a flat 12:1, as any lower starts to rob you of power an is just rumming the engine too rich. If the car is overheating, then there is something wrong with the Coolant system.

I'm running 13:1 afrs with water methanol injection. Engine sits at about 79 degrees after a few hard runs.

I'd only go richer if its pinging and taking timing out doesn't stop it in that area, but I have never come across this so I don't you should either.

this is what I run without WMI as promised:

Edited October 4, 2007 by Guilt-Toy

[The Mafia]

well, of course your going to run that kind of richness at that power and boost, but that kind of boost is probably too high? Have you considered looking at a turbo that provided more flow? Or maybe some cams?

Remember, boost is bad, its a measure on how much the engine is resisting the air your trying to push into it.

But if your talking 11.2:1 afrs, I still thats simply too low for even your setup. I'd look at 11.5 - 11.8. All you need to do is watch the knock, and I bet if tuned properly, there wouldn't be any at all any way.

Its not the fuel (to an extent) you should be focussing on when you want the engine to last, its timing. Pull the timing out if you think its going to ping \ blow up \ be running on edge.

Edited October 4, 2007 by The Mafia

[nissan200sx.dk]

Thanks for reply.

Picture was a big help. Thanks!

Now I have something to aim for, but how about exhaust gas temp? How high is max, before meltdown.

Best Regards

Ronni