ITB setup opinions?
#50
Slowest Progress Ever
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I just woke up and saw that...that's a pretty bad burn.
I knew what you meant though WonTon. (4) 40mm throttle bodies with short runners flow more air than (1) 60mm throttle body on a stock intake manifold.
I knew what you meant though WonTon. (4) 40mm throttle bodies with short runners flow more air than (1) 60mm throttle body on a stock intake manifold.
#51
thirdgen, you may want to consider asking people that have experience with N/A cars. I appreciate your enthusiasm about going to a N/A set up. If you do not follow the sheep here, you will be ridiculed. It really is a shame.
I told you what I thought, and it sounds like you are serious about giving it a try. Here is what I know.
An individual throttle body set up can be driven very reliably on the street.
To get good power out of the car will require a cam change, so you can expect your fuel mileage to suffer some. It's still a lightweight four cylinder car for crying out loud, so do not worry about it.
Individual throttle bodies are better than log style period. It will make more power than the intake and throttle body you have now. It has been proven many times over. All N/A Miatas that go fast in the quarter mile or race track have either individual throttle bodies or carbs.
I am going to guess that you will make about 160 hp max without cylinder head work or cams. It will still be decently fast, and will put you in the 14's in the quarter. Several N/A Miatas have gone that fast without cam and head work. Keep in mind I went in the 13 with a mildly ported 95 cylinder head. A stock 99 head flows better than my ported 95. My camshaft is not that much bigger than a stock 99 cam.
I say give it a try. I think you will lust for more power however, and end up doing head and cam. You should make a trip to Florida and drive my car when it is together.
Edit: With stock pistons, 160 hp maybe a tad optimistic. You can still get it in the 14's however.
I told you what I thought, and it sounds like you are serious about giving it a try. Here is what I know.
An individual throttle body set up can be driven very reliably on the street.
To get good power out of the car will require a cam change, so you can expect your fuel mileage to suffer some. It's still a lightweight four cylinder car for crying out loud, so do not worry about it.
Individual throttle bodies are better than log style period. It will make more power than the intake and throttle body you have now. It has been proven many times over. All N/A Miatas that go fast in the quarter mile or race track have either individual throttle bodies or carbs.
I am going to guess that you will make about 160 hp max without cylinder head work or cams. It will still be decently fast, and will put you in the 14's in the quarter. Several N/A Miatas have gone that fast without cam and head work. Keep in mind I went in the 13 with a mildly ported 95 cylinder head. A stock 99 head flows better than my ported 95. My camshaft is not that much bigger than a stock 99 cam.
I say give it a try. I think you will lust for more power however, and end up doing head and cam. You should make a trip to Florida and drive my car when it is together.
Edit: With stock pistons, 160 hp maybe a tad optimistic. You can still get it in the 14's however.
#53
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Thanks a lot for your information.
My real big question comes with tuning. How would I tune an ITB setup with my MS2 which uses a MAP sensor? I would imagine the vacuum signal must be really sucky.
My real big question comes with tuning. How would I tune an ITB setup with my MS2 which uses a MAP sensor? I would imagine the vacuum signal must be really sucky.
#54
I do not have any experience with MS. I am pretty sure getting around that problem is pretty simple.
I would suggest posting on miata.net in the naturally aspirated section. You will have to wade through the speculators that do not have a clue, but there are people over there that have done it.
I would suggest posting on miata.net in the naturally aspirated section. You will have to wade through the speculators that do not have a clue, but there are people over there that have done it.
#57
See what I mean?
1) How would he know i have a boyfriend? (His next response will be something like "cause you're gay".
2) How would he know if my boyfriend's dick would be on fire unless it was in his mouth after he ignited a shot of Bacardi 151 and followed it up by a BJ?
3) Quit while you're ahead...oh wait...you'll never be ahead of me, **** Face.
1) How would he know i have a boyfriend? (His next response will be something like "cause you're gay".
2) How would he know if my boyfriend's dick would be on fire unless it was in his mouth after he ignited a shot of Bacardi 151 and followed it up by a BJ?
3) Quit while you're ahead...oh wait...you'll never be ahead of me, **** Face.
no, but when I'm home from school, I crash in one of my old rooms.
#58
Super long post dissapeared when i tried to post but got logged off due to inactivity or whatever, so ill type again.
This is like saying all fast turbo miatas run at least 550cc injectors, what relevance does that have to someone wanting to upgrade a stock engine with just this one mod?
To quote OP "I asked that question to Jenvey, and they said that I would need to tune by throttle position and crank position. What???"
This post proves how little you should be arguing with advice you are given here.
Map signal is very shaky so you tune using CLT for correction, AIT for correction, TPS for load, and a crank angle sensor for rpm (also helps determine load), or you can run TPS until say...2k rpm the MAP after through a vac distribution block.
I have a strong 1.6 N?A and a very strong ae86 rally car which runs quads, and the only reason the quads are there are for response, even the 4age's **** plenum flows enough for 160 to 180 hp before quads show top end improvement.
4 stroke 4 bangers, like sav said, only have one cylinder on an intake stroke at any one time, and at the top and bottom of that one stroke per 2 revolutions its hardly moving, and the piston is only 78mm, and its sucking through 2 30mm ports with valves only opened 7mm so why the hell would a completely open 60mm hole restrict this?
If I put a big shiny ITB on the tip of my vacuum cleaner will it suck harder and get more vacuuming done?
Dann
To quote OP "I asked that question to Jenvey, and they said that I would need to tune by throttle position and crank position. What???"
This post proves how little you should be arguing with advice you are given here.
Map signal is very shaky so you tune using CLT for correction, AIT for correction, TPS for load, and a crank angle sensor for rpm (also helps determine load), or you can run TPS until say...2k rpm the MAP after through a vac distribution block.
I have a strong 1.6 N?A and a very strong ae86 rally car which runs quads, and the only reason the quads are there are for response, even the 4age's **** plenum flows enough for 160 to 180 hp before quads show top end improvement.
4 stroke 4 bangers, like sav said, only have one cylinder on an intake stroke at any one time, and at the top and bottom of that one stroke per 2 revolutions its hardly moving, and the piston is only 78mm, and its sucking through 2 30mm ports with valves only opened 7mm so why the hell would a completely open 60mm hole restrict this?
If I put a big shiny ITB on the tip of my vacuum cleaner will it suck harder and get more vacuuming done?
Dann
#59
Super long post dissapeared when i tried to post but got logged off due to inactivity or whatever, so ill type again.
This post proves how little you should be arguing with advice you are given here.
4 stroke 4 bangers, like sav said, only have one cylinder on an intake stroke at any one time, and at the top and bottom of that one stroke per 2 revolutions its hardly moving, and the piston is only 78mm, and its sucking through 2 30mm ports with valves only opened 7mm so why the hell would a completely open 60mm hole restrict this?
Dann
This post proves how little you should be arguing with advice you are given here.
4 stroke 4 bangers, like sav said, only have one cylinder on an intake stroke at any one time, and at the top and bottom of that one stroke per 2 revolutions its hardly moving, and the piston is only 78mm, and its sucking through 2 30mm ports with valves only opened 7mm so why the hell would a completely open 60mm hole restrict this?
Dann
It is very simple. Individual throttles have the ability to control intake speed entering that tiny valve hole you were talking about. Cast log manifolds do not.
The intake speed is higher on individual throttles (if they are tuned correctly) than any cast log manifold any day. Higher speed results in having more air/fuel in the combustion chamber. And THAT results in more power.
Did I make that simple enough for you to understand?