ITB setup opinions?
 

For the past couple of months I have been looking into an ITB setup for my car. I understand I can make way more power on a turbo setup, but to me it's about more than making BOOSTED power. I really like the idea of an engine bay that is pretty basic. If I went ITB, I would have a header, and no more big bulky intake manifold. I would have no intercooler, no intercooler piping, no BOV....just a cleaner, basic engine bay.
There are questions I still have no answers for about a setup like this.
1) How would I tune with with my MS if the intake runners are so short? I mean, how do I get a proper vacuum signal?
I asked that question to Jenvey, and they said that I would need to tune by throttle position and crank position. What???
2) What kind of fuel mileage could I expect with ITB's? I got 26mpg stock, I get about 29mpg turbo'd.
3) How do ITB's behave on a daily driven car? My Ducati 916 didn't like to cruise with the cams and chip I had in it. It liked either full throttle or idle. I'm thinking an ITB setup would be similar.
4) How much whp could I put out without swapping in custom cams or high comp pistons?

This might be a direction I don't want to go towards, but I'm just curious. I'm not expecting a lot of feedback on this, cause not a lot of people run a setup like this.
I found this setup:
http://www.jenvey.co.uk/home/standar...45-kit-ckmmz01
When I emailed them, they told me they have a distributor in Florida, and they only have a kit currently for an NB.

I also found a few videos:

ITB's were never intended to make power, they are about response.

A stock engine is not limited by the IM or the TB so why would ITB's make more power without changing anything else?

Dann

I'd love my engine bay to look like this.

I also believe that 14's on a naturally aspirated ITB setup on my car would gain more respect than my car would on a turbo setup running 13's. I mean think about it. If you have a LS-1 camaro and you get beat by a turbo Miata...you'll be like, "that thing weighs 1/2 my car, and I don't have boost...let me boost my car, then we'll see who wins". However, if you beat me, but I still can hang with you, you might say, "that thing is pretty fast, but I didn't hear it blow off. What? It's Not Boosted??? That's pretty mean!"
ITB's change the whole power band. I have read that it's full throttle power from 3000-9000 RPM.

Wrong, the length of them affects where the powerband is, just like length of runners on any IM.

I have an ae86 rally car with All the NA work done including 45mm Quads. They do NOT gain any power unless your IM or TB is a restriction which it is not on a stock miata.

Dann

just throwing out numbers here:

If you have a stock TB thats 60mm, that 60mm hole is feeding 4 cylinders. Your TB is your bottle neck. not to mention having to spread that air across 4 cylinders.

If you have ITBs that are 40mm, thats 160mm feeding the engine divided by 4. so technically you have the ability to feed more air into the engine and with short straight runners you get that supply faster.

EDIT: Not to mention that since you wont be running boost that gives you alot of room to punch those cylinders out and get some nice high comp pistons.

Exactly. The intake is not the restriction, it's the amount of air going into the intake that is.

Kill yourself

/thread

This is somewhat off topic, but im thinking about puting some weber sidedafts on my 86 golf, so I have been looking into some of this stuff! :D

I honestly don't see the appeal. You will make ZERO torque, which is what I enjoy the most with a turbo. However, different strokes.

Good luck, just remember that it takes a lot of money to get where the Fuji car is and the 949 crew is not far behind either.

You won't be "hangin" with any slightly fast cars either.

But its not, if it were that simple bugger the ITBs and just get a bigger TB, if that WERE true you dont think mazda would have just fitted a bigger TB for advertising bragging rights?

Dann

Just do a blowthru settup! You will get the best of both worlds. :bigtu:

Pusha...2 things.
Go find some other thread to crap in,
and
Fuck off.

Thats like saying they could have put a better intake on there or even a more free flowing exhaust. They cant cause they have to stick to certain standards. Im sure if they could have they would have slapped a begger displacement engine in there, but that would change the classing of the car. (Isnt there some kinda tax overseas based on your engine displacement?)

Thing is, on horsepower freak builds people tend to swap to a bigger TB to get rid of the bottle neck. Same principle as removing the cat to get better flowing exhaust.

The more air and fuel you can get in and exhaust out, the more eficient your setup will be and make some kind of power!

Shut the fuck up you stupid fucking piece of shit. Your reasons for researching an inferior setup are retarded. If you want to be fast NA, swap in an LSx. IDIOT.

Hey I forgot...you don't own a Miata do you? So what the hell are you doing here? Bragging about your dad's corvette?

why would you spend all the money to set up ITB's when you could have a cheap satisfying turbo?

U MAD

http://a8.sphotos.ak.fbcdn.net/hphot..._7133268_n.jpg

I am satisfied with my turbo, but I'm like the rest of the community, I always have to be messing around with different setups. I wouldn't even matter if I did an LSX swap...I'd still find something else I'd want to direct my attention towards.

I have the same problem! :giggle:

YO, WHAT HAPPENED TO TALKING SHIT ABOUT MY NONEXISTENT MIATA AND THE CORVETTE YOU SAY BELONGS TO MY FATHER?

It's ok, I'm sure being retarded can become frustrating.

No, I ain't mad. I just like stirrin the pot, as do you. I don't keep tabs, but when did you get that red miata? How pissed were your parents when you told them you were gay?

It is a bottleneck on a big power setup, its NOT on a stock engine, and unlike a better manifold mazda choosing to use a bigger TB is FREE!

Dann

I've had my '91 Miata for almost two years, bitch. I own three Miatas and my parents know I'm not gay because I always introduce girls I fuck to them on the way out the next morning. WHAT DID YOUR DAD SAY WHEN HE CAUGHT YOU SIPPING OUT OF HIS CUM JAR? FAGqueerGOT.

LOL!!!
Where do you come up with this stuff?!! This is funny shit! My dad's cum jar? Who's dad keeps a cum jar!?! BTW, the gay reference didn't actually mean that you were seriously gay...it was simply a miata reference. I'm not sure how you missed that one with your huge intelligence, but maybe next time you'll get it!

Read between the lines:

| FUCK YOU |

yall is makin me lulz!

Posts like this are literally dragging the quality of this forum down.

Tell me more about the 4-cylinder 4-stroke motor that is filling all 4 cylinders with air at the same time.

ONE cylinder fills at a time. You are filling ONE cylinder through a 60mm hole - assuming your ports and runners aren't more restrictive (they are).

Your geometry teacher would like to have a word with you. 40mm diameter x 4 does not equal 160mm diameter.

An engine is basically a vacuum pump...so why are those numbers wrong? 40mm per cylinder, 1 complete engine cycle. What am I missing?

x

A DESIRE FOR FEMALE CONTACT

LOL!!!! This guy is on fire!!!!

Just like your boyfriend's dick.

I was getting ready to settle down and possibly get some sleep, but everytime Pusha replies...all I do is start laughing my ass off!

:giggle:

I knows how a engine works. It sucks in fuel and air, it compresses it, then spark and combustion which pushes the piston back down and the process reapeats.

I was just giving general numbers describe the differance between drawing air from a plenum (that fills with air through a TB) and drawing air from an open source (that get pulled through 4 individual TBs).

fact of the matter is you net gains from a ITB setup wont be much more than what you can get from IHE. It just more exspensive, better throttle response and sounds cool.



Isnt one of the keys to making power better flow?

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?
3) Quit while you're ahead...oh wait...you'll never be ahead of me, Fuck Face.

40+40=80

80+80=160

so 40x4=160

:confused:

I give up. :facepalm:

I know the concept in my head, It just not easy for me to type/spit it out to explain to somone else.

Wait...he's right. It doesn't equal 160mm, but then again a 60mm throttle body on a stock intake won't equal 360mm per cycle either. So Wonton, your point is valid...math is wrong.

I think what WonTon means is...if a single stock throttle body is flowing 60mm it will disperse that much air over all 4 cylinders. However, if each cylinder is getting a 40mm throttle body, it will flow much more air per cylinder.

:bowrofl::bowrofl::bowrofl::bowrofl:

I suck at math....

Don't sweat it, it's late. Get some sleep...I'm about to. Later MT.net

Wow

http://theskyisnotblue.com/images/stuff/funny/gtfo.jpg

LOL. Still lives with parents.

Assuming a circle, 4x 40mm throttle bodies have the same area as a single 80mm throttle body.

Yes, it is facepalm.

Atleast I tried, I just over simplified the complexity.....

stupid mistake is stupid!

That diagram made me laugh my ass off..

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.

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.

Holy shit this thread makes me lose faith in mankind.

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.

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.

Wasn't meant as much of a burn really, but a picture is worth a thousand words, and I was bored...

Wow.

Just....

....wow.






Hai guiz! Hoo makes sum camberz plates so I cun just my camberz? De 240 frendz have dem an I wunt some so i can ajust muh cambers.

I'm so far ahead of you that I fell asleep before you did.

no, but when I'm home from school, I crash in one of my old rooms.

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 shit 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

I think my experience with individual throttles proves otherwise.

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?

If you want to be so different, just live under a fucking bridge.