DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Noobish question

Old 05-20-2008, 12:46 AM
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OK, so the miata has a MAF right? If you were careful could you run a turbo on a stock engine computer with low pressures? I'm talking 5psi or less above ambient. I would think that you could because your measuring mass and an increased mass would increase the fuel to the engine right? Would the O2 sensors get upset though or would it expect it?

I'm guessing that it would run a little lean but as long as you ran 93 octane or better you would maybe avoid knock.

The reason I ask is that I knew a kid that did something similar with a dodge avenger. Sorry if this comes off as blatantly stupid but it bounced around in the noggin for a while and I thought I'd ask the experts (or at least people that know more than I). All this being said though I've been working on cars for a while and I'm most of the way through my engineering degree so technical answers are welcome and appreciated.

Also if it matters my miata is a 1996

Thanks,
Frank
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Old 05-20-2008, 09:47 AM
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You could do it I suppose, but not safely by any means, your stock everything cannot compensate for the boost.
The bandaid setup that is known to work is FPR and o2 clamp and maybe bigger injectors. Do yourself a favor and read all the stickies, and do it right the first time, that's the best way to save money.
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Old 05-20-2008, 09:53 AM
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Have you read the FAQ yet?
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Old 05-20-2008, 09:57 AM
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the computer cant sense boost, we don't blow through the MAF and if you did it still would be clueless.

You can do it, but don't expect the fuel to be there....

you know what's easier? Not being a cheap *** and doing it right, even the simplest of FMUs would work....which can be source for well under $100 for a good used unit.
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Old 05-20-2008, 10:13 AM
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Originally Posted by Braineack
the computer cant sense boost, we don't blow through the MAF and if you did it still would be clueless.

You can do it, but don't expect the fuel to be there....

you know what's easier? Not being a cheap *** and doing it right, even the simplest of FMUs would work....which can be source for well under $100 for a good used unit.

Ya, I know what the right way to do things is. I've done quite a bit of reading. No need to resort to profanity and bashing please. I was just wondering what the possibilities were.
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Old 05-20-2008, 10:16 AM
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cheap *** isn't profanity nor bashing.....

profanity would be something like: **** the ******* *******.

bashing:

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Old 05-20-2008, 10:55 AM
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I'm glad we could be civil about this, I'll think twice before asking a question on here again. Thanks
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Old 05-20-2008, 11:02 AM
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Old 05-20-2008, 11:03 AM
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Old 05-20-2008, 11:05 AM
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Here's a good rule of thumb, and this is not a flame. The cars have been around since what.. 89? You think in roughly 20 years some mind greater then yours has not considered this fact? If you read about 10,000 posts here of everyone using an AFPR with a greddy kit (considering the kit comes with it) to supplement the stock ecu, there is probably a reason.

Stop being a vagina and laugh it off... this is a tough forum. On this forum you will get flamed on this board for a silly question, but at least you'll get the right answer. If you want to be coddled, go on CR.net and ask the question. You won't get the right answer, but you will not get flamed.
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Old 05-20-2008, 11:17 AM
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Yea guy. Seriously, just laugh it off and enjoy your stay.
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Old 05-20-2008, 11:20 AM
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It's like deja vu all over again. Where are they all coming from......
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Old 05-20-2008, 11:21 AM
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if this is tough....you should be scared of these pythons...

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Old 05-20-2008, 11:32 AM
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Originally Posted by levnubhin
It's like deja vu all over again. Where are they all coming from......
Really, i feel like it happens every day, someone comes in, doesnt read, gets flamed, gets pissy and leaves. Everybody gets flamed every now and again. I had to read brain's original post two or three times before i even realized what even offended the guy.
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Old 05-20-2008, 11:36 AM
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i still don't really know....
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Old 05-20-2008, 11:48 AM
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it's the
you know what's easier?
part in scotts reply...some people get insulted when you offer them a solution that's simpler than what they hoped for
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Old 05-20-2008, 12:33 PM
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What really upsets me is that I asked a question. The question was not, "I don't know anything at all about anything how do I do this?" I was asking from the standpoint of feasibility. But instead of giving me an answer like, "This won't work because..." Or, "That might work but...." I have people who really are not interested at all in the question that I asked and basically just wanting to tell me I'm stupid. By doing this the only question that has been answered is that yes you are a jerk more interested in putting me down than having a conversation, and not worth my time to talk to.

Let me put it to you this way. I know the "right way" (although saying there is a "right way" precludes that there is no other way and seems like an oxymoron to me) to handle the engine management, I even own a megasquirt, weee!!! Other than a manifold, DP, and a bit of wiring I'm basically set to go.

The original question above was brought to me by another person who is extremely knowledgeable and I figured I would ask because the way it was put to me seemed plausible. So next time you decide that you want to flame go ahead, but your really just making yourself look like an ***.

PS: For all of you that said "read the FAQ" or something similar, I did and I'm fairly certain that my original question is not answered in there.
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Old 05-20-2008, 12:35 PM
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Miatas are gay car...that means no pussies allowed...give it a rest.



the best answer is this: the ECU doesn't have a MAP sensor to know how much air flow there really is. While it can meter the airflow using the MAF, it's not enough to tell it ultimately what's going on. So when you have 5psi in there, it simply thinks you are WOT, have lots of air, and can meter the temps. It's just not smart enough to add fuel fuel based on boost unlike other cars like Hondas where there is a MAP sensor and fuel maps extending into boost.

So like I said, the easiest thing to do is an FMU. When you add boost, it raises the fuel pressure in relation. Giving you the extra fuel required from stock injectors.
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Old 05-20-2008, 12:38 PM
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Originally Posted by tonybennett3000
What really upsets me is that I asked a question. The question was not, "I don't know anything at all about anything how do I do this?" I was asking from the standpoint of feasibility. But instead of giving me an answer like, "This won't work because..." Or, "That might work but...." I have people who really are not interested at all in the question that I asked and basically just wanting to tell me I'm stupid. By doing this the only question that has been answered is that yes you are a jerk more interested in putting me down than having a conversation, and not worth my time to talk to.
Let me put it to you this way. I know the "right way" (although saying there is a "right way" precludes that there is no other way and seems like an oxymoron to me) to handle the engine management, I even own a megasquirt, weee!!! Other than a manifold, DP, and a bit of wiring I'm basically set to go.

The original question above was brought to me by another person who is extremely knowledgeable and I figured I would ask because the way it was put to me seemed plausible. So next time you decide that you want to flame go ahead, but your really just making yourself look like an ***.

PS: For all of you that said "read the FAQ" or something similar, I did and I'm fairly certain that my original question is not answered in there.
You are wrong! We love having conversations here. We just hate having converstions about things that have been talked about hundreds of times. Had you taken an hour or so and searched around you would have gotten your answer.
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Old 05-20-2008, 12:39 PM
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I think it's more like a natural selection: T-rex eats littlefoot the dinosaur. Nom Nom Nom
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