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Fuel management help..

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JJsx

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Discussion starter · #1 ·
Aight I need to know what fuel management system, piggy back or stand alone system should I get for a stock Ka24de? I want to boost it but not anytime soon.

looking for something with a reasonable price and easy to play around with and that can be tuned when I go KA-T.
 
#2 ·
I mean really there's no need for anything right now, but if you feel the need to absolutely spend money then I would just go with an Apex'i S-AFC II or NEO. While the KA's do run a bit on the rich side whilst stock, an FMU is nothing you need to have on your car. If you're only putting it on because it looks cool, that's even further the wrong reason.
 
Discussion starter · #3 ·
I'm not doing to just look cool haha... but someone awhile back on this website said start with fuel management tuning before I drop a turbo in my KA, because I'm still kinda new to the boost'n life.. but I'll look into the A-AFCII and the NEO because the KA really does run rich
 
#4 ·
unless u have some crazy intake mods as far as head porting and such, tuning wont be of much help to you, remember you tune to get in a balance, as of now stock is balanced. only when u force induction or more than stock induction, i think a tuning would be required.
 
Discussion starter · #5 ·
aight gotcha, gotcha ... I'll wait on the tuning until I drop a t25/t28 in it or something. what FMU will be good for a small turbo upgrade like that? I was looking at the ultimate but dang! I aint ballin in dough haha... you think a pretuned JW will work aight?
 
#6 ·
gabo said:
unless u have some crazy intake mods as far as head porting and such, tuning wont be of much help to you, remember you tune to get in a balance, as of now stock is balanced. only when u force induction or more than stock induction, i think a tuning would be required.
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Stop posting advice, because your post not only makes no sense, but it's completely wrong.

You tune to get the ratio between the air and fuel balanced at 14.3:1 which is what is considered to be a stoich mixture, granted many of us tune a fair bit leaner than this.

With that said, whilst the KA does run a bit rich while stock I would just wait to spend the money on an S-AFC and tuning when the time comes to turbo it; it'll just be money spent on a dyno tune that really doesn't need to be spent right now.
 
#7 ·
Dark-Hawk said:
Stop posting advice, because your post not only makes no sense, but it's completely wrong.

You tune to get the ratio between the air and fuel balanced at 14.3:1 which is what is considered to be a stoich mixture, granted many of us tune a fair bit leaner than this.

With that said, whilst the KA does run a bit rich while stock I would just wait to spend the money on an S-AFC and tuning when the time comes to turbo it; it'll just be money spent on a dyno tune that really doesn't need to be spent right now.
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I'm going to have to go ahead and say FAIL. You tune for your goals. There are different AFR's that yield different results. 14.7:1 is stoichiometric and is best for emissions. That's why OEM's set it to that, to get through the EPA's testing. If you're tuning for power 12:1 is about the best, but fuel economy will suffer. 16:1 is about best for fuel economy, but max power will suffer. Picking up a FMU when you can afford if in not a bad idea, just so you can get used to tuning for your goals with a less volatile engine. As for a suggestion as to what to use, a few of my friends use Apexi units and are happy with them, but there are much better options for the long term. I have Megasquirt 2, but it's pissing me off right now, but if you want to learn about fuel and spark management it's a good option, but I've heard people haven't had good luck with them in their DD's. Good luck.
 
#8 ·
one30five said:
I'm going to have to go ahead and say FAIL. You tune for your goals. There are different AFR's that yield different results. 14.7:1 is stoichiometric and is best for emissions. That's why OEM's set it to that, to get through the EPA's testing. If you're tuning for power 12:1 is about the best, but fuel economy will suffer. 16:1 is about best for fuel economy, but max power will suffer.
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Apparently you failed with reading comprehension.
 
#9 ·
So what you're saying is that when you increase airflow (Boost, or radical porting like gabo said) you don't need to adjust fuel? A stock ecu can compensate for added air to a point, but at some point it will not be as effective. Also, a stock ECU generally likes to keep the engine at a stoich mixture. If he wants to richen it up a bit for a little more power, he can do that with an aftermarket fuel management system. That and i don't get why you would tune to be lean in a car you want better performance from, unless that isn't your goal.
 
#10 ·
If you got that out of my post you need to reread it, or are atleast reading into me telling him he's wrong a bit too much.

Yes fuel needs to be added when there is an increased amount of air - thus why I noted that you tune to keep the air and fuel to a certain ration; the stoich mixture of 14.3:1 being what is considered the "ideal" ratio on a gasoline vehicle. You do not however add more fuel (than what is considered stoich for your given setup) to extract more power, you tune leaner than a stoich mixture to do so.

While an ECU does often times try and tune for a stoich mixture, that isn't exactly the case with the 240's due to the fact that they come from the factory running a bit rich. Thus why often times people will tune their mostly stock/bolt on 240's with an S-AFC to help lean them out and extract more power.

More fuel does NOT equal more performance though.
 
#11 · (Edited)
"We mentioned the stoichiometric air-fuel ratio (14.7:1) that is the ideal ratio for lowest emissions, but this isn't the best ratio for power. It used to be that 12.5:1 was considered the best power ratio, but with improved combustion chambers and hotter ignition systems, the ideal now is around 12.8:1 to 13.2:1." A quote from Car Craft Mag.

http://i527.photobucket.com/albums/cc358/one30five/powerout.gif
Chart from the Megasquirt manual.

These sources plus others, and my experience with our schools FSAE car tell me stoich isn't the optimal ratio for power. Not yet anyways, but maybe with engine advancements, someday it will be. But i don't see this discusion ending any time soon, because I don't see my opinion changing given my current facts. That, and we kinda jacked the thread, so I think I'm done..
 
#14 ·
Unless your goal is to turn your engine into a oxyacetylene torch aimed at the pistons faces, then leaner then 13:1 is a baddddd idea under any sort of load condition such as wide open throttle.
14:7 is a cruising/very partial throttle position tune for optimal gas mileage. You can even go as low as 16:1 for cruising under certain circumastances. But never, ever tune for much a condition under load, you will burn the faces of the pistons.

For some reason, I don't think your grasping the meaning behind the numbers. Stoch is 14.7 to 1, meaning 14.7 parts air to one part fuel.
 
Discussion starter · #15 ·
thanks for all the ratio to ratio options. but i just want to fine tune on my stock KA and get a grip on how it works. I think S-AFC will be my best bet right now and then work on getting a stand alone or piggy back system when I boost it.
 
#16 ·
Oh lol...

Your best off getting it now. You could do a Calumsult or Nistune which make your stock ECU tunable in real time. That or a megasquirt. Those seem to be the best bang for the back at the moment.
 
Discussion starter · #17 ·
aight sounds good. I'll look into the Calumsult or Nistune, I never heard of them. well I don't think so. still have a lot to learn


* where's a good place to learn about tuning. I need to know what I'm getting into before I start this haha
 
#19 ·
JJsx said:
aight sounds good. I'll look into the Calumsult or Nistune, I never heard of them. well I don't think so. still have a lot to learn


* where's a good place to learn about tuning. I need to know what I'm getting into before I start this haha
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I would suggest learning tuning from a published source. Books, mag articles, megamanual (principles of tuning section is quite thorough).
 
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