I have had a flowed TB now for a while, which had been fitted then removed due to fuel economy probs, flat spot that arose after fitting some headers. This problem was traced back to a faulty O2 sensor. Now that the car is running very well with market ably better fuel economy, I refitted the flowed TB hoping for further improvements. But alas whilst the throttle is snappier, fuel economy is worse. I am at a loss as to why this is so, as most people have experienced better fuel economy amongst other benefits after fitting a modified TB.

I have been very conscious of driving the car the same, whilst obtaining fuel from the same servo, driving the same route so as to get a fair comparison between the 2 TB's, but with my TL AWD VRX I get better fuel economy/performance with just the headers, Barry's fuel rail kit, unmodified TB, standard filter and NZ CAI.

So what are peoples experiences with their flowed TB's??

Have you gained better fuel economy??

I am after constructive comments/suggestions as to why I am experiencing the reverse, to what others are experiencing.

well mine isnt a TL but ez boy bored mine 5mm wider and im getting about 10/100ks no matter how i drive the 2.6l, try resetting the computer see how it helps because you arnt getting any more air in its just taking a smoother path

try resetting the computer see how it helps because you arnt getting any more air in its just taking a smoother path

That was the first thing I did, took it Mits to have the TPS set/reset and this again made no difference.

I am starting to think that it is getting more air with the smaller throttle openings, as when the restrictions where there, the lower part of the butterfly had to rotate further in order to clear the restriction on the rear of the butterfly, but the top of the butterfly cleared the restrictions earlier. So in affect under small throttle openings air was only passing over the top of the butterfly. Now with the restrictions removed, as soon as the butterfly opens and at smaller throttle openings, its getting more air as air is passing past both sides of the butterfly earlier.

More air = more fuel under light throttle openings.

I could be wrong. :confused:

It will run leaner under small throttle openings, so whether the computer is shoving more fuel in to compensate is hard to say, it's possible I suppose.

I've had a HF TB on my TJ for about 3 weeks now and have noticed no improvement in fuel economy but it appears to be no worse either. Haven't really noticed a difference, I keep a pretty close eye on consumption. The only other mods I have is a K&N panel filter and sports muffler.

high flowed TB's do nothing.. i dyno'd my car.. fitted the high flowed TB while the car was on the dyno and ran it straight away and saw zero improved.. just makes the car FEEL more responsive because you dont have to push the acclerator down as far...you can do the same thing by pushing the pedal down a bit further with your standard TB

your motor can only suck in X amounts of air, the TB is probably not a restriction to this, so by making it larger wouldn't make a difference.

For arguments sake, say you could put on a throttle body that was MASSIVE, say like half a meter (I know impossible but for arguments sakes) if it was possible, but the motor would still suck in the same amount of air. So you wouldn't be making anymore power.

It would really just cause problems with tuning.

Until your car flows so good, ported heads, exhaust etc... when the TB starts coming a restriction, then by putting a larger one will it start making a difference. And even then you still might need a tune.

So on a relativity stock car, it really wouldn't do much most of the time.

your motor can only suck in X amounts of air, the TB is probably not a restriction to this, so by making it larger wouldn't make a difference.

For arguments sake, say you could put on a throttle body that was MASSIVE, say like half a meter (I know impossible but for arguments sakes) if it was possible, but the motor would still suck in the same amount of air. So you wouldn't be making anymore power.

It would really just cause problems with tuning.

Until your car flows so good, ported heads, exhaust etc... when the TB starts coming a restriction, then by putting a larger one will it start making a difference. And even then you still might need a tune.

So on a relativity stock car, it really wouldn't do much most of the time.

i disagree... a larger throttle body has proven to make more power... when i say a larger TB im talking about replacing the butterfly with a larger unit and boring out the TB.. these high flow things arent bigger... there the same over all size with the same butterfly..they grind off a bit of the TB .. doesnt make it any larger or let any more air in at WOT.. they are a waste of time... oversized TB's arent

yeah it all depends how good the motor was designed in the first place.

If you had some pissy little 2L 4 cyl, its not sucking in alot of air, and if the TB was designed good it would not be obstructing the flow of air at all.

So by improving on this TB by whatever means probably wont make any difference what so ever. Until you start improving other areas of the car which makes the engine breath easier then the TB might not be able to flow the required amount of air.

Say you an engine with some extensive headwork then it would be flowing alot more air then usual, and of course the TB wasnt designed with this sort of flow in mind, so then upgrading at this point would be a smart move.

In other words, a larger TB isnt a good move for a gain in power by itself, but of course on stock engines it could always help a little bit as not many things are designed perfectly.

Read this (http://www.aussiemagna.com/forums/showthread.php?t=39009&highlight=throttle) thread

I agree with gremlin..:P I just threw 80mm TB one on..:)

I agree with gremlin..:P I just threw 80mm TB one on..:)

In my opinion, Throttle body size is like exhaust size. A larger one will improve performance up to a point. How much depends on how much of a restriction the factory unit is (if at all), and the capacity of the engine, and go too big and I wouldn't be surprised if you saw a reduction in performance.

With the work you've done, particularly the cams and flow work - you're engine is capable of using more air, hence the factory Throttle body would have started to become abit of a restriction.

Anyway - thats not really relevant to the OP's question, because a flowed throttle body isn't oversized. I don't know why someone would expect to see an improvement (or a reduction for that matter) from fitting a flowed throttle body, all it is doing is increasing the air flow at low throttle. The ECU will sense the increased airflow and add more fuel to compensate.

well in response to the original question, i also did this around 3 weeks ago, and only noticed a smoother acceleration. this was most noted in the s**thouse traffic i was in when making a 2hr journey into 4hrs on thursday night. the smaller pedal pushes when in crawling traffic were less jolty to passengers. thats about it. my fuel economy did not change.

your motor can only suck in X amounts of air, the TB is probably not a restriction to this, so by making it larger wouldn't make a difference.

For arguments sake, say you could put on a throttle body that was MASSIVE, say like half a meter (I know impossible but for arguments sakes) if it was possible, but the motor would still suck in the same amount of air. So you wouldn't be making anymore power.

It would really just cause problems with tuning.

Until your car flows so good, ported heads, exhaust etc... when the TB starts coming a restriction, then by putting a larger one will it start making a difference. And even then you still might need a tune.

So on a relativity stock car, it really wouldn't do much most of the time.

Hi Ascension, If your saying a higher flow TB is useless because its sucking in more fuel but not more air would this be the same with a carby?
Cause it was suggested to me to get a stage 2 TB for better power. He also said because the cars done 170kms the TB on it now may be pouring more fuel in and not going through as fast? So if i got a Bigger TB would it not give me more power?

Firstly: I have a vested interest in high flowing throttle bodies because I have found it to be beneficial. Others might not have, everyone to their own. What I will do is share some experiences and conclusions that i've been privy to while being involved in this and other projects.

The fact of the matter is most members use there cars as daily drivers and enjoy not having to mash their throttle to get through the traffic grind. I drive 2hrs a day and swapping an unflowed tb into my car recently caused me to near have a melt down as I had to gas-stop-gas-stop instead of my usual coast-stop..

Additionally, manual cars respond very well with smoother low rpm traffic gearchanges along with faster high rpm changes like on my TF 5spd. My mrs near shot me when I sold that tb!

If you want hp go get an 80mm bolt on, change your cams, do some head work etc. If you want your driving experience more relaxed and comfortable then flow your stock tb. Not everything good for you is proven by a dyno.

Flick thru this and read the experiences of people who've got HF TBs. Click me. (http://www.aussiemagna.com/forums/showthread.php?t=16412&highlight=throttle+body)


So what do other cars run?

VN-VT V6 Commodores run 60mm tbs, straight cut - no lip.
5L V8s get a 65mm tb which bolts upto the v6s. 1st basic mod for any commodore owner esp if you've got the supercharged motor.

For laughs we oversized a 60mm tb right upto 70mm including a new butterfly. With a full exhaust, the test VR picked up 23hp atw!! But not until 3700rpm did the 2x graphs start to seperate.

So how useful then is a 70mm tb on a VR commodore driving along parramatta rd heading east at 8:15am monday morning??

So how useful then is a 70mm tb on a VR commodore driving along parramatta rd heading east at 8:15am monday morning??

lol 3700rpm in a 3.8L commo is like 6000rpm in my car

by highflowing the TB you aren't really letting much more air in. i thought this thread was going to be about getting a bigger butterfly (e.g. out of a falcon) and using a lathe to make the hole bigger in the TB so that the bigger butterfly fits in. that actually allows more air through.

any intake mod is going to increase fuel usage. the reason being that accelerating at any given rpm or load (except idle) there will be more air going through the airflow meter, so it registers the air and puts in more fuel to keep the AFR's the same. while cruising you won't use any more fuel, but whenever you put your foot down you will.

does anyone know what size the butterfly is on a TH 3.5L?

I have all of Barry's Kits, and fitted a flowed (NOT bored) TB and my fuel economy has decreased :( I'm not quite sure why as I drive the same... before the TB with just Barry's kits on the economy was quite a bit better than stock, but the TB seems to have killed that...

poita, you are obviously getting more air into the motor, and once the ecu sees more air going in it puts in more fuel.

HiFlo TB allows u to provide sufficient feed of mixture (air first, of course) to the engine with small TB opening. That's all. Trick is to learn to feather the gas pedal to utilise the benefit. Took me few weeks to learn not keep pumping (and slightly over-accelerating) the gas pedal. Every time u press the gas pedal, the TPS feeds more gasoline. With HiFlo TB, less gas pedal pressing is required to achieve similar action, than what STD TB would do. So, if u keep pressing the pedal like u used to, the consumption would be higher cos more air actually is getting thru and consequently more fuel is fed.
Consider also: on very small BF opening, say 2 mm, u are cruising on low steady speed. Press the pedal a bit, say another 2 mm and it goes bit more etc. But note, that is 100% increase. What I'm trying to say is that with HiFlo TB, at small BF openings, the actions are relatively bigger compared to STD TB.

HiFlo TB does not really increase total power, just functionality. Bigger bore TBs do, up until certain bore size for specific engine size is reached. Any larger size just makes bad flows. STD TB has been designed as an average compromise for a family car - it is not the best performance type of design by any means.

BTW, engines do not suck air, surrounding air pressure fills the void created by descending piston. Think of high altitudes and NA engines vs forced inductions..... :)

BTW, engines do not suck air, surrounding air pressure fills the void created by descending piston. Think of high altitudes and NA engines vs forced inductions..... :)

No, engines do suck air and the above mentioned is how they do it. If they didn't suck air in then they would not be engines.

BTW, engines do not suck air, surrounding air pressure fills the void created by descending piston. Think of high altitudes and NA engines vs forced inductions..... :)
So what you are saying is the descending piston creates a void which is then filled by in by air which is sucked in by vacuum which is created by the void left by the descending piston? lol

The fact of the matter is most members use there cars as daily drivers and enjoy not having to mash their throttle to get through the traffic grind. I drive 2hrs a day and swapping an unflowed tb into my car recently caused me to near have a melt down as I had to gas-stop-gas-stop instead of my usual coast-stop..

Additionally, manual cars respond very well with smoother low rpm traffic gearchanges along with faster high rpm changes like on my TF 5spd. My mrs near shot me when I sold that tb!



I'm with EZBoy on this one. I am using a loaner TB from him while he flows my original, and my TF 3.0 Tiptronic Sports is light years more responsive from zero to 2,500rpm. Much easier to drive in town and no tuning dramas, increased fuel usage or any that other stuff you don't want in your everyday car with a big TB. Haven't noticed anything in the high end of the rev range on the auto. But that's no surprise given that the car will kickdown when you hammer it at high revs anyway. If I manually select a gear and hold at high rpm, then yes there is a little more responsiveness.

But in answer to the original question, no change to fuel consumption whatsoever.

I'm with EZBoy on this one. I am using a loaner TB from him while he flows my original, and my TF 3.0 Tiptronic Sports is light years more responsive from zero to 2,500rpm. Much easier to drive in town and no tuning dramas, increased fuel usage or any that other stuff you don't want in your everyday car with a big TB. Haven't noticed anything in the high end of the rev range on the auto. But that's no surprise given that the car will kickdown when you hammer it at high revs anyway. If I manually select a gear and hold at high rpm, then yes there is a little more responsiveness.

But in answer to the original question, no change to fuel consumption whatsoever.

Sorry about going abit off topic here =p but i thought id jump in while where on the topic.
If i was to get a bigger bored TB it would increase my power ( im running a carby ).
From what im reading is that the case or am i wrong? :bowrofl:

any intake mod is going to increase fuel usage.

Not if it increases efficiency at your normal operating rpm. I.e. replacement inlet manifolds.


the reason being that accelerating at any given rpm or load (except idle) there will be more air going through the airflow meter, so it registers the air and puts in more fuel to keep the AFR's the same. while cruising you won't use any more fuel, but whenever you put your foot down you will.

does anyone know what size the butterfly is on a TH 3.5L?

The object of effective throttle body sizing is to make volumetric efficiency it's highest at your desired operating rpm hence improving available power AND economy at that point.

If you want high rpm power then go with a big bore tb. If you want better mid-high; select multiple tbs of similar or higher cross sectional area to increase air velocity. For low rpm smaller tbs and runners etc are needed to get air velocity up and fill the cylinders efficiently when the valves are open.

All 3rd gen V6s have a 65mm butterfly.

Every little piece of the puzzle has it's place in the grand scheme. A high flowed or oversized tb is just another piece of that puzzle.

:)

Additionally, many member have 4sp autos, my awd is a 5sp auto. Another variable in the fuel econ debate. :think:

Not if it increases efficiency at your normal operating rpm. I.e. replacement inlet manifolds.



The object of effective throttle body sizing is to make volumetric efficiency it's highest at your desired operating rpm hence improving available power AND economy at that point.

If you want high rpm power then go with a big bore tb. If you want better mid-high; select multiple tbs of similar or higher cross sectional area to increase air velocity. For low rpm smaller tbs and runners etc are needed to get air velocity up and fill the cylinders efficiently when the valves are open.

All 3rd gen V6s have a 65mm butterfly.

Every little piece of the puzzle has it's place in the grand scheme. A high flowed or oversized tb is just another piece of that puzzle.

:)

So the lower the TB size the more lower rev pickup your gonna get?

So the lower the TB size the more lower rev pickup your gonna get?
And your top-end will be breathless.

And your top-end will be breathless.

Ethier way i cant win! :( i want more pickup but they want 3grand for a lower ratio diff!!! :shock: :shock: i told them to :gtfo:

So what you are saying is the descending piston creates a void which is then filled by in by air which is sucked in by vacuum which is created by the void left by the descending piston? lol

Hehe. Gentlemen. The speed of air filling a void is greater then the speed of the descending piston creating the "vacuum". Hence it is classified as the domination force.
Anyway, enuff of that endless argument. Believe what u wish, cool with me. I have no need to change your opinions. :)

Installed TB from EZ Boy today.What a difference.Wonder why I did not do it years ago. Face expression from 1 pm today whenever I had to go for a drive :D . Will post more after a while.

Hehe. Gentlemen. The speed of air filling a void is greater then the speed of the descending piston creating the "vacuum". Hence it is classified as the domination force.


Engines don't suck - air pushes.
Vacuum is a lack of air pressure.
The faster you can get air into the void the more air/fuel mix you can ignite to produce power. Turbo's and SC's push the air in faster than "normal" air pressure, the ECU programs richer fuel mix and voila bigger bang.

If "The speed of air filling a void is greater than the speed of the descending piston creating the "vacuum" there would never be any lack of air pressure because the air would fill the void before it wasn't there. :redface:

:bowrofl:

The speed of air filling a void is greater than the speed of the descending piston creating the "vacuum"[/I] there would never be any lack of air pressure because the air would fill the void before it wasn't there. :redface:
:bowrofl:

Valves. And camshaft operating them. U kinda explained that your self too, didn't u. With the forced induction stuff. Well done tho. Funny how no one realised my note about higher altitudes (like mountian rallies) where NA engines lack power unlike forced indutions. Cos the "forceful airpressure" is not filling as well as down on sea level. Funny physics isn't it!

But if TB is painted Ferrari red, would it iincrease the power? :shock:

High flowed the TB on my TL VRX AWD, as said before by someone else, "less jolty" in stop start traffic. There appears to be no significant change to fuel economy, maybe a bit worse, but then again, I have to contend with more sheeples in my drive to a new office. High flowing significantly improved the drivability in slow traffic. The low speed tuning of the Magna VRX AWD is garbage.

Ken

The low speed tuning of the Magna VRX AWD is garbage.

Amen Brother. You meant the gearbox of course, yes?

I am yet to put my throttle body on the car which I bought from EZ Boy(too busy at work). I am looking forward to putting it on though, extra throttle response can't be measured by a dyno.

Some individuals have quoted higher fuel economy LOL...... of course , even if psychologically unitentional whenever you modify the engine you are ALWAYS going to give the car an extra squirt here & there. Try the fuel economy test a month later once you are used to the extra throttle response. I will post my experience with the TB next week when it goes on the car.

I'm sure I'll get told if I'm wrong, but I think there is a little bit more to this than just removing the lip. Isn't there attached to the same shaft as the butterfly, a potentiometer that gives a signal back to the ECU that tells the ECU how far the butterfly has been opened?

If I'm right, this would mean that the ECU expects for a certain butterfly opening, a certain air flow. If that is the case (and as far as I'm aware, nobody is playing with the potentiometer and its position on the shaft relative to the butterfly) then the ECU would still be receiving a signal says to expect X amount of air and actually getting X+Y amount.

Would someone who understands how the whole engine management system works like to comment? I don't think that the flowing of the TB (and the increased airflow) can be treated in isolation from the whole system.

Roble

So in simple terms a high flowed, blueprinted if you will, as opposed to enlarged TB smooths power deliver? Some people claim power improvements, more likely better response, while others claim similar economy. Not really fussed about more power, just better response and economy, since wife drives it.

I'm sure I'll get told if I'm wrong, but I think there is a little bit more to this than just removing the lip. Isn't there attached to the same shaft as the butterfly, a potentiometer that gives a signal back to the ECU that tells the ECU how far the butterfly has been opened?

If I'm right, this would mean that the ECU expects for a certain butterfly opening, a certain air flow. If that is the case (and as far as I'm aware, nobody is playing with the potentiometer and its position on the shaft relative to the butterfly) then the ECU would still be receiving a signal says to expect X amount of air and actually getting X+Y amount.

Would someone who understands how the whole engine management system works like to comment? I don't think that the flowing of the TB (and the increased airflow) can be treated in isolation from the whole system.

Roble
In conjuntion with the airflow meter, yes. The potentiometer in the TPS is set quite finely for low rpm esp throttle opening - since higher rpm operation would be even more-so adversely effected by incorrect tps setting. The air flow meter can also add fuel based on air movement and is apparently roughly equal in determining fuel requirements due to the construction of the fueling maps (i.e. rpm vs engine load TPS vs air volume, temperature, pressure etc).

In a nutshell there's enuf scope for the system to know whats going on when air is passing the butterfly at say 5deg (in a correctly flowed TB) vs approx 12-15deg (oem tb) of butterfly opening.

It just may add power to some parts of the rpm range, just people on this and many forums seem obsessed with peak power. I'm just happy to not have to work so hard behind the wheel to get what I need done each day. If you want a high-spec motor then removing this deliberate deformation in the TB to enhance air flow, is another string in the bow.

For some reason I can now access the forums :D Bloody computers.

Thanks for all the replies. I have been trialling different combinations and for some reason, when I add the flowed TB into the mix fuel usage increases, whereas if I take it out of the equation fuel economy becomes better than when it was stock. :confused: When I get back from Melbourne I will refit the flowed TB and leave it on for some months to see if things improve over time.

I certainly like the throttle feeling that the flowed TB gives, but not the added fuel consumption. I know that with the AWD that whilst accelerating regardless which TB is on the car the same amount of throttle is needed to get the heavy bugger moving. I have been very conscious of paying attention to the go pedal movement. The only real advantage that the flowed TB seems to give me is a smoother transition through the gears like Ken N and others have stated.

EZ boy would you be so kind as to explain how you set up the TPS, etc on the flowed TB's that you sell.

Again thanks for the input :D

OMG WTF

A high flow throttle body can ONLY make a difference to power at WOT compared to WOT.

The throttle responce you are noticing is simply because you are having to put your foot down less to have the same amount of valve actuation. In essence you are being tricked in to thinking it is going harder, but in reality, it is nothing you couldn't have gotten with the old throttle by allowing the same amount of air in, but having to use a little bit extra throttle.

It also screws with your TPS sensor because the sensor is calibrated for a specific sized throttle valve, not a larger one.

If you can't understand that, you shouldn't be modding cars.

I just don't get how some of you folks are using extra fuel when you fit the flowed TB. I have been running my EZBoy TB for 3 weeks now. Two tanks of fuel, fuel consumption identical to what it was before.

Because they think they are getting power from nothing. The same throttle position is making more power.

OMG WTF

A high flow throttle body can ONLY make a difference to power at WOT compared to WOT.

The throttle responce you are noticing is simply because you are having to put your foot down less to have the same amount of valve actuation. In essence you are being tricked in to thinking it is going harder, but in reality, it is nothing you couldn't have gotten with the old throttle by allowing the same amount of air in, but having to use a little bit extra throttle.

It also screws with your TPS sensor because the sensor is calibrated for a specific sized throttle valve, not a larger one.

If you can't understand that, you shouldn't be modding cars.

So your saying you get a high flow TB isnt gonna increase your power? Is that also the same with Bigger bored TBs?

So your saying you get a high flow TB isnt gonna increase your power? Is that also the same with Bigger bored TBs?
Not enough to warrent the effort. I doubt it would be measurable and for that matter proven by reliable sources.

They are generally already oversized from factory, to the point where any larger will not make any more power as there are other restrictions holding it back.

There are ofcourse exceptions, but none that I have had experience with. I have fitted a few of the earlier high-flow units from RPW and they made no difference to MPH or ET.

same reason most vn commodores have dinted front bars

it had a pivot point closer to the throttle shaft thus less accelorator made them feel like they had more punch,

yes a bigger throttle body is better but you need more fuel and bigger valves and a good exhaust system to benifit from it.

I would also like to question the theory behind a high-flow throttle, which is supposed to increase fuel econ and power by allowing smoother flow throught/past the throttle.

Last time I checked, the throttle plate was there to SLOW DOWN FLOW and to disrupt it, except for at WOT.

The way EFI works, is the air is let in by the throttle, and metered by the MAF, and fuel is added accordingly. The throttle peddal is linked straight to the throttle body which is just a valve to let in air to the motor.

If you want to go slow, you open the throttle a little bit. If you want to go fast you open the throttle all the way.

By making the throttle larger, you simply have more flow at the same throttle % than a smaller throttle, so more air and fuel goes in. This isn't anything magic, you could have the same amount of performance from just a little more throttle.

Similarly with a high-flow throttle. The de-burred or smoothed valve now just lets in more air because its flowing a little smoother. If you wanted that extra air in to the motor, you would have opened the throttle. This gives you a smaller window of throttle in which you can cruise and lightly accel with, anoying you and making the car harder to keep economical

You are not making the engine work less for its air, because the throttles single purpose is to make it hard!

**admin edit - dont bypass the swear filter**

Uh... So one person says it does give a gain and the other does .. -_-

The person selling them says they do ;)

Uh... So one person says it does give a gain and the other does .. -_-

How dense are you?! Read turbo charades posts!

How dense are you?! Read turbo charades posts!

And what about all the guys who HAVE bought one!!! They like em. And no one claims more POWER, just better response. So I don't see why the hell we are arguing.

The person selling them says they do ;)
:gtfo: If you can quote me anywhere on AMC that high flowing a TB will give you a definative power gain, I will send you $100.

It is however a fact that the lips and the angle of the top wall of the TB impede air flow upto and past the butterfly at part throttle. If you open you're bonnet and check it you'll see it. :redface:

Maybe you should retire to the turbocharade (interesting word "charade") forum and pretend to be controversial to the other 2 members on there. But thanks for stopping by.

Maybe too you should research why I am providing them for AMC members. Facts go a long way in the real world. We stopped burning witches some time ago. Did you know the Earth is round?


Folks who know me know I don't get drawn into drivel and bla-bla matches like this but I'm so sick of this merry-go-round and people hiding behind online anonymity.

If you want more power, force feed it or radically change the air volume entering the engine. That's it, end of list. Bored now.....

And what about all the guys who HAVE bought one!!! They like em. And no one claims more POWER, just better response. So I don't see why the hell we are arguing.

Thank you. Facts. Gotta luv em.

Have you read a word I said?

Any responce noticed is simply more air getting past because of the slight porting or "high flowing"

Obviously you don't understand that?

Have you read a word I said?

Any responce noticed is simply more air getting past because of the slight porting or "high flowing"

Obviously you don't understand that?
No, I'm referring to your previous accusation that I am advertising a power gain by purchasing my product. Btw, did you check you Magna throttle body?

(this is the part where you reply and I don't reply giving you the impression that you've had the last word - as you're famous here for doing. That's a lot of work racking up 3200+ posts!)

So no power gains from your product, yet a bigger throttle body can only make a difference if it is a restriction, to top end where velocity is at its best, and the rest of the throttle range is just off-set flows compared to what you are used to?

3000 posts, and still going strong pointing users in the right direction mate ;)

OMG WTF

A high flow throttle body can ONLY make a difference to power at WOT compared to WOT. Maybe, maybe not. Non wot postions at some rpm bands (say at 4500rpm where torque is peaking) may experience a power gain, can it be measured on such a soft tuned road car :cry:


The throttle responce you are noticing is simply because you are having to put your foot down less to have the same amount of valve actuation. In essence you are being tricked in to thinking it is going harder, but in reality, it is nothing you couldn't have gotten with the old throttle by allowing the same amount of air in, but having to use a little bit extra throttle. It's not a trick - that's the aim. Less foot movement for more action. I drive 1.5hrs a day in <60kph traffic. Many members do. Why can't I have a comfortable drive to work? Am I going to pick a race with a skyline or SS at 8:15am monday morning on parramatta rd?


It also screws with your TPS sensor because the sensor is calibrated for a specific sized throttle valve, not a larger one. 3rd Gen V6 tps can be calibrated to a large variation in butterfly angle as much as the backstop permits. Just got to have a multimeter and know how to use it. Each TB can be individually calibrated, unlike say an ecotec commodore tb which is fixed and moving the backstop screw will increase TPS output even if you don't want it to. Any serious customer would be using a piggy back or signal modifier if they were worth the flesh they're printed on.

Maybe, maybe not. Non wot postions at some rpm bands (say at 4500rpm where torque is peaking) may experience a power gain, can it be measured on such a soft tuned road car :cry:

Okay, but at non WOT, if you wanted more power you would just put a tiny bit more throttle down ;) thats my point.





3rd Gen V6 tps can be calibrated to a large variation in butterfly angle as much as the backstop permits. Just got to have a multimeter and know how to use it. Each TB can be individually calibrated, unlike say an ecotec commodore tb which is fixed and moving the backstop screw will increase TPS output even if you don't want it to.

The TPS is a position indication for the ECU. It is only used to by the engine to add additional fuel to the engine on quick blips of throttle. Basically like a carbi throttle pump, but electronic. The ECU detects throttle change (TPS change) and knows a set amount of air is getting in, and fuels for it. The set amount of air is tuned per engine. Now you go and change the size of the throttle, that same throttle change adds more air because of the modified throttle, but the ECU doesn't know this and still adds the same old amount of fuel.

This will cause lean outs, hesitations and flat spots when the throttle position is increased at any fast rate.

The calibration you are talking about is to let the ECU know when the throttle is closed, not the sweaping position of the throttle. This has to be set via the multimeter so that the closed throttle switch is in the closed position at 0% throttle and open at the slight crack of the throttle. The ECU uses this information to cut fuel on decel.

No, I'm referring to your previous accusation that I am advertising a power gain by purchasing my product. Btw, did you check you Magna throttle body?

(this is the part where you reply and I don't reply giving you the impression that you've had the last word - as you're famous here for doing. That's a lot of work racking up 3200+ posts!)

Theres a pretty handy trick i use for a few members on here, click on their username, click view public profile then click "Add to ignorelist" works a treat, now I dont need to read the ever positive TC's posts anymore :)

in regards to throttle bodys. they are ment to be slightly narrow in the center its called a venturi it speeds up air flow.
by removing it your slowing the air speed down.

Geesshhh - we have a WAR! :D
Venturi is not touched in these HiFlo TBs, only the step before BF. This allows better airflow on very small BF opening thus providing slightly better functions - if learned to feather correctly. Lead footers would not discover any diff, I'd say.
With HF TB, drive slight up hill at 60 km/h and 4th gear (auto). Keep lifting off just mm at tiime and u'll realise it just keeps pulling without losing speed. Due to better flow on small BF opening.
I don't think anyone has claimed that HF TB provide more power, no. Just slightly better funtiocn if correctly used on small BF opening.
I'm going for coffee now, tired.... :cool:


in regards to throttle bodys. they are ment to be slightly narrow in the center its called a venturi it speeds up air flow.
by removing it your slowing the air speed down.

Turbo_charade, I like your technical content, quite informative. However, as experienced by EZ Boy and others when driving in stop-start traffic, the auto box is snatchy and there is a lag between small throttle movement and vehicle response. This feels, to me, like you are out of sync with the traffic. They move, my foot goes down, they stop, my vehicle finally responds, oh, too late, now I have to stop, just when the engine has finally wound up.

When I took the lip off the the throttle body, it resulted in less lag between leg movement and vehicle response. Hey, maybe I'm getting old, but, when compared to other cars I've driven over 25 years, I didn't like how it responded before the TB mod. So, sure I could have used more throttle, but I didn't want to. I want a snappy throttle response. Maybe that's old school.

Has anyone actually checked if the changed throttle flow at part opening causes leaning out on quick throttle movement?

Ken

Howdy Ken N
(had my cafe fix!) U're correct. Ppl often wonder why that lip was there. It was to stop jerky actions in slow busy traffic when operated by a bicycle type pumping by Cardigan Drivers, not gentle footed hoon-asses like us. :)

Has anyone actually checked if the changed throttle flow at part opening causes leaning out on quick throttle movement?

Ken

Don't Magnas run a little rich from factory (to compensate for not having a knock sensor). So a slight lean out might actually make a touch more power at lower rpm on slight throttle openings (thats if it does in fact lean out the mixture a little).

While I will admit that you get more power from your foot movement, making the auto engage the stall converter earlier, you could have the same effect by modifying the swing arm that the cable pulls.

Or you could put your foot down a little more.

Phonic, while I have never put my wideband sensors on a magna, throttle pumps are generally about as lean as they can be. This saves sudden gushes of extra fuel which can not burn and cover the rear of the car with soot. It is evident with pod filters. As soon as there is a slight lean out, the car hesitates. This shows how close to the edge most throttle pump tuning is.

The pod does the hesitation from other reasons, but the symptom is still the same, a slight lean out causes a hesitation.

The pod does the hesitation from other reasons, but the symptom is still the same, a slight lean out causes a hesitation.

Ahh fair enough, I suppose thats why allot of people seam to get flat spots with CAI/filter changes on the Magnas.