View Full Version : Twin throttle manifold
cthulhu
25-08-2005, 08:02 AM
So I got my car back yesterday, finally.. haven't had a chance to really put it through its paces yet, mostly because I noticed the weld on the rear-most exhaust mounting braket is busted and the muffler is wafting in the breeze.
And the exhaust is really too loud right now.. have to do something about that asap.
But anyway.. here's a pic of the twin throttle setup I got. Good news is that cruise control is retained. Click for the full image.
http://www.wermspowke.net/images/engine-bay-tn.jpg (http://www.wermspowke.net/images/engine-bay.jpg)
heathyoung
25-08-2005, 08:10 AM
Very interesting - who does these?
I remember that CAPA did a twin throttle body jobbie for a Hyundai Excel years ago, made quite an appreciable difference to on a dyno!
Cheers
Heath Young
cthulhu
25-08-2005, 08:15 AM
Very interesting - who does these?
Dallas from Street Torque in Alice Springs. Same guy who did Booya's car.
:o i want another one! so many things to want to do... who in WA would do this ?
Interesting cthulu.
I thought they would have added a 2nd pod or air intake at least. How exactly is that benefitting the car if its still coming in through the 1 standard intake? Same amount of air, just being pushed in through 2 sides instead of 1..
I would assume the closest TB would have more air entering as its a shorter run.. :think:
Was a seperate dyno run before the twin TB's were added?
sola|2a
25-08-2005, 09:11 AM
Interesting cthulu.
I thought they would have added a 2nd pod or air intake at least. How exactly is that benefitting the car if its still coming in through the 1 standard intake? Same amount of air, just being pushed in through 2 sides instead of 1..
I would assume the closest TB would have more air entering as its a shorter run.. :think:
Was a seperate dyno run before the twin TB's were added?
same thoughts here!
cthulhu
25-08-2005, 09:46 AM
Interesting cthulu.
I thought they would have added a 2nd pod or air intake at least. How exactly is that benefitting the car if its still coming in through the 1 standard intake? Same amount of air, just being pushed in through 2 sides instead of 1..
I would assume the closest TB would have more air entering as its a shorter run.. :think:
Was a seperate dyno run before the twin TB's were added?
Agree with your first point. The main issue though is that I'm using a piggy back not a full replacement ECU which means I have to keep the MAF sensor in service. I am looking at running a second pod from the t/b on the left but it'll mean some extensive retuning since the MAF will effectively only ever be reporting half the actual air flow. It should be possible, however.
A dyno run was done before and after. Actually about 135 seperate dyno graphs where made of my car over all lol and yeah, it did make a couple of extra ponies but it wasn't life changing stuff.
Honestly without plumbing in a couple of pressure gauges it's impossible to tell to what extent the second t/b is being used, and it's going to come down to manifold vacuum to dictate how much air gets drawn in anyway, but for any given throttle opening I have twice the area through which to draw air.
Agree with your first point. The main issue though is that I'm using a piggy back not a full replacement ECU which means I have to keep the MAF sensor in service. I am looking at running a second pod from the t/b on the left but it'll mean some extensive retuning since the MAF will effectively only ever be reporting half the actual air flow. It should be possible, however.
A dyno run was done before and after. Actually about 135 seperate dyno graphs where made of my car over all lol and yeah, it did make a couple of extra ponies but it wasn't life changing stuff.
Honestly without plumbing in a couple of pressure gauges it's impossible to tell to what extent the second t/b is being used, and it's going to come down to manifold vacuum to dictate how much air gets drawn in anyway, but for any given throttle opening I have twice the area through which to draw air.
Good answers mate :)
Glad to see youre a realist! So your next step is a full ECU replacment huh ;)
I suppose in the end, if you got it in for some major mods, you may aswell lay a road to your next step in modifications.
cthulhu
25-08-2005, 10:44 AM
Glad to see youre a realist! So your next step is a full ECU replacment huh ;)
Nice idea, but I'm not sure another $1300 for an ECU and 6 hours for wiring and 12 hours for tuning to get roughly the power I'm already making is really good value for money ;)
I suppose in the end, if you got it in for some major mods, you may aswell lay a road to your next step in modifications.
What I'd like to do next is investigate the mod I mentioned above re the 2nd throttle, and then throw in some 230 degree duration cams. Aim for 180-200kW ATW naturally aspirated.
I reckon that'll about do me then. I need to start saving for my next car :cool:
WogsRus
25-08-2005, 10:47 AM
I do not see how that would benifit the car at all. Having it set up that way does not do anything, and may actually hinder performance. Each 90 deg bend couses large losses, and the air in the intake would be getting confused as to what it is doing. The way the air is distrubited in a manifold is that with every storke and valve shut a high pressure wave is created. When the valve opens again the air is then pushed in. This happpens in the manifold aswell. With two intakes that pressure buildup would decrease. BUT hay if it works good on ya. Looks good and profesional. I recon a single large throttle body would be wiser setup.
bondy
25-08-2005, 11:43 AM
Each 90 deg bend couses large losses, and the air in the intake would be getting confused as to what it is doing.
Was going to say this too. Three 90deg bends!
tfv630
25-08-2005, 12:08 PM
The bends appear to be mandrel bent so no real loss's there. But i too think a singe big throttle body would be the way to go. Something like and 80mm or bigger with some 276deg cams, 11-1 compression, balanced bottom end and an aftermarket ecu would gain some valuable power. May not but you never know
megatron
25-08-2005, 12:34 PM
where the air filter???
any reason why a single pipe was not made instead of or those expense silicon hoses??
looks good
DaJaJa
25-08-2005, 12:39 PM
interesting.......
so what were the gains from doing just the twin throttle manifold???
J-PaP
25-08-2005, 12:58 PM
well good thing is youve removed any kind of restriction that there was after the maf. But the tubing from before the maf i think could be improved on. that kind of tubing creates turbulance which reduces the velocity of the air. where is your air filter? You had mentioned it was twin 65mm throttle bodies right? Think that is a little too big for the current setup. Should work well though with the new cams etc. Just a neatness thing i dont like... the random lengths of silicon tubing along the pipe? also with aluminium tubing going around the motor.. doesnt it heat up a fair bit?
M4DDOG
25-08-2005, 01:10 PM
Ok i'm not exactly the most mechanically minded here, but i dont see how that setup could benefit you all that much. Wouldn't most of the air being sucked up go straight into the right throttle body as the pressure would have to be fair bit higher on the left side to make the air divert into the 2nd piping and travel a much larger distance? But from what you've said both throttle bodies have the same pressure?
Wouldn't it be better to have the pipes at equal lengths to the throttle body?
Other than that it looks good :).
_stonesour_
25-08-2005, 01:14 PM
why didnt they put the metal piping all the way around instead of having those blue elbows .... im just talking from a aesthetic point of view ....... but damn! big thumbs up for being the 2nd most powerful NA around :D!!!
why didnt they put the metal piping all the way around instead of having those blue elbows .... im just talking from a aesthetic point of view ....... but damn! big thumbs up for being the 2nd most powerful NA around :D!!!
I think its more of a cost thing.
Welding those joins, then having to grind down the weld spots and repolish takes quite a bit of time. Also, if you are out by 1cm you gotta start again.
_stonesour_
25-08-2005, 01:24 PM
yeah u make a good point
tfv630
25-08-2005, 02:22 PM
Ok i'm not exactly the most mechanically minded here, but i dont see how that setup could benefit you all that much. Wouldn't most of the air being sucked up go straight into the right throttle body as the pressure would have to be fair bit higher on the left side to make the air divert into the 2nd piping and travel a much larger distance? But from what you've said both throttle bodies have the same pressure?
Wouldn't it be better to have the pipes at equal lengths to the throttle body?
Other than that it looks good :).
Just to point out to those that cant figure it out the driverside of the engine bay is still the right side of the car not the left
Reigns
25-08-2005, 05:40 PM
Looks fancy, but 1 big mumma throttle body would be better. Just cause its got two pathways now, doesnt mean ur gonna be taking any more air in like that. Only way would to be have a dual CAI setup.
BOosted' BOoya
25-08-2005, 06:51 PM
equal air flow to all intake runners.
enough said.
its not a huge proformance mod - but it leaves future open a lot. also going on what i said above, its so ALL runners are receiving equal air to all cylinders. = hp in its self.
brendan; i think you'll see more hp then you think if you got a full aftermarket ecu.
Screamin TE
25-08-2005, 08:55 PM
This is only a though, but it is something EZ Boy and myself had a quick chat about last week.
What f you got another MAF sensor, and spliced the wires in with the original MAF sensor.
IE, two independent throttle bodies, air filters and maf sensors, signalling the ECU. You would effectively double the air flow, and the signal wouldnt you?
Cheers,
Chris
_stonesour_
25-08-2005, 09:00 PM
what if diferent MAF's were getting slightly diferent readings though wouldnt that freak the ecu out ?
J-PaP
25-08-2005, 09:02 PM
nah the two signals would add together like a parallel circuit. more than likely ull overload the ecu and blow something.
heathyoung
26-08-2005, 07:02 AM
The MAF gives a frequency output in the magnas IIRC - so with two different airflow amounts, you would have two different frequencies - How the ECU would interpret this is anyones guess...
Cheers
Heath Young
Ralliart-AKKO
26-08-2005, 07:08 AM
I seem to remember the booya-mobile having a similar setup to this once upon a time, does anyone still have any pics of that, Booya?
Black Beard
26-08-2005, 08:06 AM
I seem to remember the booya-mobile having a similar setup to this once upon a time, does anyone still have any pics of that, Booya?
Don't know about pic's but I know what you're talking about - from memory the had independant air intakes - 1 for each T/B, however (I asked this question in the "Got some mods done" thread), Booya was running full aftermarket ECU at the time, so the MAF sensor wasn't an issue.
BOosted' BOoya
26-08-2005, 09:57 AM
Don't know about pic's but I know what you're talking about - from memory the had independant air intakes - 1 for each T/B, however (I asked this question in the "Got some mods done" thread), Booya was running full aftermarket ECU at the time, so the MAF sensor wasn't an issue.
attached;
that pic with those metal shavings was how much dallas ported the heads and intake manifold.
it was baby bottom smooth!
TZABOY
26-08-2005, 03:34 PM
thats an awsome mod and good figures. 165 kw's puts you up there with the power of my car.
Bench flowing the heads and high profile cams will definatly see you with 180-200kw's at the wheels in N/A form. I'm currently looking at either doing that or giving sprintex a call.
Well done dude
_stonesour_
26-08-2005, 04:38 PM
whats ur latest power reading TZA boy? latest mods ? ....
hey guys im curious... this is a question for all u fellas with +150 atws ... whats ur torque figure ? i know it cant be measured heaps accurate unless its done on an engine dyno but should still get a indication atw's ...
mine which was dyno'd at 130 atws ... ( well 129.7 DOH at the .3!) and had 358NM at 122km/h ...
oh on second thought i can only really compare to 5 speed auto's and manuals done in 4th gear right ? as the restwould have a different ratio ? or am i wrong ? ...
anyways TZA boy, rolliart, Jason VRX, CTCHULU *how ever u spell ur name :P ... enlighten me
TZABOY
26-08-2005, 06:07 PM
whats ur latest power reading TZA boy? latest mods ? ....
hey guys im curious... this is a question for all u fellas with +150 atws ... whats ur torque figure ? i know it cant be measured heaps accurate unless its done on an engine dyno but should still get a indication atw's ...
mine which was dyno'd at 130 atws ... ( well 129.7 DOH at the .3!) and had 358NM at 122km/h ...
oh on second thought i can only really compare to 5 speed auto's and manuals done in 4th gear right ? as the restwould have a different ratio ? or am i wrong ? ...
anyways TZA boy, rolliart, Jason VRX, CTCHULU *how ever u spell ur name :P ... enlighten me
I've got around 530NM but dont know what speed off the top of my head. My mods are as follows;
*Standard Ralliart headers with pacemaker underneath.
*2½ inch straight through exhaust with stainless muffler (no resinators)
*RPW flowed throttle body
*K&N pod filter with 3 inch stainless pipe from MAS sensor to TB
*Insulator blocks
*RPW oversized plenium with ram tubes
*Unichip piggyback ecu tuned to 98 octane fuel.
She's putting out around 166kw atw's and this is on a manual Ralliart. Sorry to hijack your thread CTCHULU, but what are all the mods on your car?
KX_69
26-08-2005, 08:13 PM
thats an awsome mod and good figures. 165 kw's puts you up there with the power of my car.
Bench flowing the heads and high profile cams will definatly see you with 180-200kw's at the wheels in N/A form. I'm currently looking at either doing that or giving sprintex a call.
Well done dude
GO THE SUPERCHARER!!! plzzz
cthulhu
27-08-2005, 10:30 AM
Haven't been around for a couple days, but to catch up on all the comments..
I'm surprised by the volume of negative feedback :confused: but each to their own. The MAF is almost definately going to be restricting the amount of power I can create eventually, but perhaps not right now. After all, Jasons VRX is making over 171kW ATW from his car and he's only using one (overbored) throttle drawing through the standard MAF. The cams are my limiting factor at the moment.
There was an increase in power over the whole range after fitting this mod, but as I said to Bain, it wasn't huge. So it wasn't a complete waste of time. As TZABOY points out, hotter cams and there's heaps more power to be had.
I agree that the corrugated tube down to the pod isn't going to be helping. Of course I didn't know it had corrugated tube until after I got the car back :( which is the downside of sending it 1500km away to get modded. I'll try and find some smooth piping to replace it with.
And Booya, if you want to spot me the cash to get the full ECU done, I'm more than happy to give it a go ;)
Don't know what my torque value at the wheels was, since that'll be different depending on what gear it was dynoed in, and since it is torque at the wheels it doesn't mean a whole lot anyhow. I got my dyno graphs with power and AFR instead of torque.
TZABOY - see here (http://www.aussiemagna.com/forums/showthread.php?t=23237&highlight=mods) for current mods. Bigger cams planned! No forced induction.. save that for my next car.
As for twin throttles vs one big mumma throttle body, to get the same total area created by two 65mm throttle bodies with one throttle, I'd need a 91mm throttle body. Know where I can get one? ;)
_stonesour_
27-08-2005, 12:49 PM
I've got around 530NM but dont know what speed off the top of my head. My mods are as follows;
*Standard Ralliart headers with pacemaker underneath.
*2½ inch straight through exhaust with stainless muffler (no resinators)
*RPW flowed throttle body
*K&N pod filter with 3 inch stainless pipe from MAS sensor to TB
*Insulator blocks
*RPW oversized plenium with ram tubes
*Unichip piggyback ecu tuned to 98 octane fuel.
She's putting out around 166kw atw's and this is on a manual Ralliart. Sorry to hijack your thread CTCHULU, but what are all the mods on your car?
what gear was that in? ... im gessing 3rd ?
BOosted' BOoya
27-08-2005, 01:46 PM
in the magna - manual transmission (and also applies for the 5 speed auto) 4th gear is 1:1 with the engine -so you'd be getting as close as you can get to a half decent torque figure in 4th gear
all dyno runs should be done in 4th, not 3rd.
i read this somewhere.
_stonesour_
27-08-2005, 01:53 PM
yes thats what i been told to .......530NM is huge if thats in 4th gear ... thats more than what a mates VU ss ute got ... ( round about i know its hard to measure it atws )
cthulhu
27-08-2005, 02:02 PM
in the magna - manual transmission (and also applies for the 5 speed auto) 4th gear is 1:1 with the engine -so you'd be getting as close as you can get to a half decent torque figure in 4th gear
But you have to take the wheels into account, because that will alter the torque figure.
A stock XR6T makes 450Nm of torque and I can guarantee you that a naturally aspirated 3.5L engine doesn't make more torque than a forced induction 4L.
Jasons VRX
27-08-2005, 05:47 PM
Jamie(_stonesour_) when i rebuilt my engine back in 2001, we engine dynoed it and it recorded 208kws@ 6250rpm and 390Nm@3800rpm then when fitted back in the car it dynoed up with 161Kw's@wheels.
Now it has 171.2Kw's@wheels, so that would probably see the flywheel figure up around 220-225Kw's
Killer
29-08-2005, 10:53 AM
We engine dynoed it and it recorded 208kws@ 6250rpm and 390Nm@3800rpm then when fitted back in the car it dynoed up with 161Kw's@wheels.
Now it has 171.2Kw's@wheels, so that would probably see the flywheel figure up around 220-225Kw's
390 Nm out of a 3.5 na donk is an excellent figure. Rule of thumb is anyting above the donk size is great (ie 350 Nm from 3.5 L and 300 Nm from 3.0 L etc).
Bema M3 3.2 L kicks 370 Isaacs out of the donk, so you're in great class there.
For those who are interested, the power loss in Jasons VRX is ~23 %. Not that u can blindly apply the percentage to any other power output situation.
_stonesour_
29-08-2005, 01:28 PM
was talking to mate yesterday ....... got onto the subject bout magna tb's and how the MAF screws us up so we cant really play around with it to much .... anyways .. apparently VN's have 80mm TB and run a MAF.. is that a possibilty? or impossible/untrue ?
Ice_Magik
29-08-2005, 01:51 PM
Maf Or Mas ?
_stonesour_
29-08-2005, 01:52 PM
oops i mean MAS
Black Beard
29-08-2005, 03:29 PM
390 Nm out of a 3.5 na donk is an excellent figure. Rule of thumb is anyting above the donk size is great (ie 350 Nm from 3.5 L and 300 Nm from 3.0 L etc).
Bema M3 3.2 L kicks 370 Isaacs out of the donk, so you're in great class there.
For those who are interested, the power loss in Jasons VRX is ~23 %. Not that u can blindly apply the percentage to any other power output situation.
I would have thought it would be lower than that - my TJII auto on a roller dyno completely bog stock recorded a figure exactly (give or take a few thousanths) 25% less than the factory rated 155kW.
So even if the difference in drivetrain loss auto -> manual was +5%, it wouldn't take much to build up a magna auto that could bridge the gap between the 2 transmissions. I know where my next couple of grand is going :badgrin: .
BOosted' BOoya
29-08-2005, 03:31 PM
i wouldnt be surprised if a higher HP magna looses more through the driveline then a stocker due to extra friction in the flywheels, extra heat, and slippage.
cthulhu
29-08-2005, 03:40 PM
was talking to mate yesterday ....... got onto the subject bout magna tb's and how the MAF screws us up so we cant really play around with it to much .... anyways .. apparently VN's have 80mm TB and run a MAF.. is that a possibilty? or impossible/untrue ?
Most likely not. The Magna uses a MAF sensor that outputs a frequency that varies with the volume of air passing through it.
Almost all other makes of car have a MAF with a variable voltage output.
Oh and I believe MAF Sensor and MAS are the same thing.. Mass Air Flow Sensor, or Mass Airflow Sensor ;) The other type of sensor is a MAP, or Manifold Absolute Pressure, sensor.
EZ Boy
30-08-2005, 07:26 PM
was talking to mate yesterday ....... got onto the subject bout magna tb's and how the MAF screws us up so we cant really play around with it to much .... anyways .. apparently VN's have 80mm TB and run a MAF.. is that a possibilty? or impossible/untrue ?
3.8L = 60mm and they use a hotwire mas
5L = 65mm, hotwire too.
These TB's are interchangable. Thats why you can't find a 65mm TB at the wreckers: they're already snatched up.
Killer
02-09-2005, 06:44 AM
Reaching my fav issue - "bagging" the Magna Auto box.
Again, I'm using Bema as a sample (kind of bench mark?). Firstly Bema 3.0L produces more power than Magna 3.0, but - also the better auto'box provides better performance out of the car. I'm talking about 0-100, 1/4 mile, consumption etc stuff. Yes, such car costs way more than Magna, but I just wanted to make a point this early Fri morning.
Sigh.
So even if the difference in drivetrain loss auto -> manual was +5%, it wouldn't take much to build up a magna auto that could bridge the gap between the 2 transmissions. I know where my next couple of grand is going :badgrin: .
Black Beard
02-09-2005, 07:06 AM
Reaching my fav issue - "bagging" the Magna Auto box.
Again, I'm using Bema as a sample (kind of bench mark?). Firstly Bema 3.0L produces more power than Magna 3.0, but - also the better auto'box provides better performance out of the car. I'm talking about 0-100, 1/4 mile, consumption etc stuff. Yes, such car costs way more than Magna, but I just wanted to make a point this early Fri morning.
Sigh.
Just because no ones ever made a Magna auto better - doesn't mean it can't be done.
(Tuff auto box > Manual) for 0-100, 1/4 mile
cthulhu
02-09-2005, 07:52 AM
Firstly Bema 3.0L produces more power than Magna 3.0
The what?
BlackD
02-09-2005, 08:16 AM
So I got my car back yesterday, finally.. haven't had a chance to really put it through its paces yet, mostly because I noticed the weld on the rear-most exhaust mounting braket is busted and the muffler is wafting in the breeze.
And the exhaust is really too loud right now.. have to do something about that asap.
But anyway.. here's a pic of the twin throttle setup I got. Good news is that cruise control is retained. Click for the full image.
http://www.wermspowke.net/images/engine-bay-tn.jpg (http://www.wermspowke.net/images/engine-bay.jpg)
is it just me or is there not an air filter? the mas is in the engine bayis the filter wayyy down at the front bumper?
cthulhu
02-09-2005, 08:18 AM
the mas is in the engine bay is the filter wayyy down at the front bumper?
Spot on.
Killer
02-09-2005, 10:10 AM
Now I'm baffled - what didn't u understand?
The what?
cthulhu
02-09-2005, 10:50 AM
Now I'm baffled - what didn't u understand?
Bema = BMW, or something else?
BlackD
02-09-2005, 10:53 AM
Spot on.
now doesnt that create all that turblance up to the MAS? never mind dont wanna dicuss this again... lol
Killer
02-09-2005, 12:00 PM
Ah yep, the brilliant products of Bayerische Motoren Werke in Deutchland (Germany)
And I was refering to 330i auto'box with 190 kW, 300 Nm, 0-100 6.88 sec, 1/4 m 14.81 according to Motor Mag BFYB test some weeks ago.
Bema = BMW, or something else?
benny_TE
02-09-2005, 02:18 PM
man that has to be so bad for your air flow meter, shouldn't it be reading air directly after the filter ? like rpw's cold air kit, thsmokers cai kit etc ?
i like the fact that you've gone and done something different, but im not so sure if this kit has been well thought out or designed .....
i guess it blings up your ride
EZ Boy
02-09-2005, 07:27 PM
Ah yep, the brilliant products of Bayerische Motoren Werke in Deutchland (Germany)
And I was refering to 330i auto'box with 190 kW, 300 Nm, 0-100 6.88 sec, 1/4 m 14.81 according to Motor Mag BFYB test some weeks ago.That's a lot of money for another 1-2seconds difference. What are the comparative vehicle weights? Rims & Tyres used etc.
Sounds like a challenge needs to be put out to the local Bimmer club. Mind you if you're in Newcastle and a silver 2dr 325ci lines up, leave it alone - it runs a VS-1 centrifugal and moves along quite smartly...
cthulhu
03-09-2005, 11:10 AM
man that has to be so bad for your air flow meter, shouldn't it be reading air directly after the filter ? like rpw's cold air kit, thsmokers cai kit etc ?
I like how you said that without providing any reasons why the filter should be right next to the air flow meter, except that everyone else's CAI kit does it.
So why should it be next to the MAS?
On the other hand I have no drivability problems, no idling problems, and nearly 165kW ATW, so it can't be all bad, eh?
cthulhu
03-09-2005, 11:43 AM
Ah yep, the brilliant products of Bayerische Motoren Werke in Deutchland (Germany)
And I was refering to 330i auto'box with 190 kW, 300 Nm, 0-100 6.88 sec, 1/4 m 14.81 according to Motor Mag BFYB test some weeks ago.
The 330i isn't a fair comparisson for manual vs auto though because you can't buy a manual version lol
Redav
03-09-2005, 01:46 PM
So why should it be next to the MAS?
Personally I think the MAF should be left the same distance from the TB, (like yours), as it is from factory. Doesn't really matter about the filter from the MAF. Either way you're clutching at straws if you try to be too techy - stuff all difference.
The benefit I see is that it's the filter getting dirty, not the MAF as well.
_stonesour_
03-09-2005, 02:21 PM
on the issue on Throttle bodies ........ had a quick talk to a guy from BTR performance ( responsible for some very tuff turbo's in adelaide) gave me a very ruff quote of $495 for an 85mm TB using the MAS
dont think id really need one that big but thats anawsome price!! RPW should lift their game or ppl will end up getting custom stuff from workshops and at a CHEAPER price
anyways i reckon a ruff price of 495 is quite good considering ... though id be happier with 75mm -70mm though
Killer
05-09-2005, 09:35 AM
One thing I was thinking about - does the air sensor require the incoming air to flow straigh (non spiralling movement - it swirls in the CAI tube) to get proper reading? I believe we have been debating this occasionally and the reason for airfilter to be somewhat close before the sensor is to disallow the spiralling? Or is it all theoretical and makes no much diff in real life?
Also, what is the required distance of the sensor from TB? Does it matter?
Just something to ponder on Mon morning. After 2 short blacks, cos I still b-dy can't wake-up my brain (if I ever can....).
Personally I think the MAF should be left the same distance from the TB, (like yours), as it is from factory. Doesn't really matter about the filter from the MAF. Either way you're clutching at straws if you try to be too techy - stuff all difference.
The benefit I see is that it's the filter getting dirty, not the MAF as well.
cthulhu
05-09-2005, 09:47 AM
One thing I was thinking about - does the air sensor require the incoming air to flow straigh (non spiralling movement - it swirls in the CAI tube) to get proper reading? I believe we have been debating this occasionally and the reason for airfilter to be somewhat close before the sensor is to disallow the spiralling? Or is it all theoretical and makes no much diff in real life?
Also, what is the required distance of the sensor from TB? Does it matter?
Just something to ponder on Mon morning. After 2 short blacks, cos I still b-dy can't wake-up my brain (if I ever can....).
I can only imagine that swirly air, if there is any, has a lower pressure at the centre of the vortex.. which might be why the MAF likes to see 'straight' air flow.. Redav can probably answer that (don't you work with fluid dynamics guys?).
However at the mo I'm running yucky ribbed/corrugated pipe down to the air filter which is probably creating so much turbulence I can't imagine there is any swirling going on.
Redav
05-09-2005, 10:18 AM
I can only imagine that swirly air, if there is any, has a lower pressure at the centre of the vortex.. which might be why the MAF likes to see 'straight' air flow.. Redav can probably answer that (don't you work with fluid dynamics guys?).
However at the mo I'm running yucky ribbed/corrugated pipe down to the air filter which is probably creating so much turbulence I can't imagine there is any swirling going on.
Yeah, I do. I'll flick an email to them. I'm not actually in the same office as them at the moment. I go on a 6 week break shortly and then I'll be back in the main office. :cry:
benny_TE
05-09-2005, 12:57 PM
yeah cthulhu, dont get me wrong i think your kit is great, i was just told by my friend (when installing my cai and pod), that the AFS should be right next to the pod. I dont know the reasons behind it, but i thought it was something to do with spiralling of the air. Like straight after the air filter the air is relatively straight (apparently) and therfore the afs can get an accurate reading of the volume , temp etc of the the air . But maybe the difference is so small it doesn't affect power in real-life, just theoretically .
i would like to hear from someone who actually knows something about this for a fact (that engineer guy, or mitsiman), it would be interesting to see what they say
later
:cool:
ps. please run you rcar down the quarter !
cthulhu
05-09-2005, 01:21 PM
Like straight after the air filter the air is relatively straight (apparently) and therfore the afs can get an accurate reading of the volume , temp etc of the the air
Good call.. and supposedly this is the same reason why a regular circular pod filter causes havoc but an oval filter doesn't. However as I said somewhere else I don't think my ribbed tube would allow the air to spiral because of the turbulence that must occur near the edge of the pipe - not that I've got any way to verify that ;) And just to throw a spanner in the works, I'm fairly sure I'm not using an oval pod lol
Believe me if I'd had any drivability or general weirdness problems I'd have changed things straight away, but so far it all seems to be good.
ps. please run you rcar down the quarter !
I'm trying! Next street meet isn't until September 30 :cry:
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