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air intake
Posted: Wed Aug 27, 2008 11:38 am
by zuihoujueding
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... :IT&ih=009
guys, check this out. 100mm pipe. is it too big for the intake? please give me your comments!
Posted: Wed Aug 27, 2008 1:46 pm
by Bennoz
Ask him how big the end is that connects to the throttle body... its 65mm OD.
Posted: Wed Aug 27, 2008 2:37 pm
by zuihoujueding
if i were to use a silicon 90 degrees couple at the throttle body. is 63mm or 70mm be alright or too big/small for perfect fit?
Posted: Wed Aug 27, 2008 5:14 pm
by zuihoujueding
Bennoz wrote:Ask him how big the end is that connects to the throttle body... its 65mm OD.
65mm diameter is referring to gpx version or same to all fto?
Posted: Wed Aug 27, 2008 6:30 pm
by Bennoz
65mm outside diamtre is standard acrossd the board.
I've used a 75mm 90 degree bend & the hose clamp pulled it in tight enough for it to be air-tight.
Posted: Wed Aug 27, 2008 8:01 pm
by I8A4RE
Bennoz wrote:65mm outside diamtre is standard acrossd the board.
I've used a 75mm 90 degree bend & the hose clamp pulled it in tight enough for it to be air-tight.
What SIlicone piping??
Just remember kiddies...... the air flow is restricted by its smallest point. So if you have a 65mm throttle body theres no point having piping thats 100mm as a bottlenecked will be created at the TB point. Also all diameter changes chould be made as gradual and smooth as possible
Posted: Wed Aug 27, 2008 8:07 pm
by I8A4RE
also it has been found on many occassions that buying cheap air filters has actually caused a LOSS in power. Personallly i wouldnt touch anything but K&N or HKS super flow
Posted: Wed Aug 27, 2008 8:26 pm
by zuihoujueding
I8A4RE wrote:also it has been found on many occassions that buying cheap air filters has actually caused a LOSS in power. Personallly i wouldnt touch anything but K&N or HKS super flow
thanks for the comments! will work out the air intake to be best of my ability and ofcos within my budget. probably will get a cannon type filter or a pod filter from 3A racing.
It actually outperformed most big filter brands including K&N/HKS.
Posted: Wed Aug 27, 2008 8:32 pm
by Bennoz
The term 'throttle' is an engineering term & it means to reduce size & increase speed. The whole prupose of a throttle body is to decrease the available volume area of the intake, hence compressing the air & making it more dense for better combustion.
There are 2 positive side effects to this, when the gas is compressed, it increses speed (good for getting more air into the combustion chambers), it also drops in temperature (also good for combustion & engine temps.)
The theory is exactly the same as used in your common household fridge of freezer. All fridges have gas lines on the inside & outside. The inside lines are full of refrideration gas (such as R134A) running cold - hence cooling the inside of the fridge. Those gas lines then exit the inside of the fridge to the outer lines on the back of the fridge. Usually black alloy lines that run down to the base of the fridge. When in those outside lines, the gas is warm & when travelling down the lines looses a lot of its temperature - towards the end of the outside lines, it hits the throttling valve. Much like a cars throttle body, the throttling valve compresses the air to a smaller area - hence cooling the gas & speeding it up - of course the cooled gas then enters the inside of the fridge cold again.
Question is - will the effects of violently throttling the air, be out-weighed by a non violent transition. Aka - Is going from a 100mm pipe to a 65mm inlet rapidily, bad for engine performance? Hard to say... While an intense throttling will drop the temperature much more than normal, it will also increase the air speed more too - will the turbulence created be bad for induction? Turbulent air is usually regarded as bad, hence most intakes are a gradual decline in size.
I dunno, I reckon someone should try it. Would the extra speed, lower temperature & turbulent air gain more on the dyno? Or would a slower air, milder cooling temp & smoother flows win out?
Posted: Wed Aug 27, 2008 9:01 pm
by I8A4RE
Ben im sure you have looked closely at the throttle body. If you have you would notice that the smallering (i dont the techincal term and am sllighty drunk and very tired) is very subtle and very smooth. A drastic and large change, i gaurantee will have a very negative effect. Thats why all professional intake piping (especially on turbos and intercooler piping) is done with mandrel bends or this new sectional welding.
The throttle is like a venturie in a carby exactly the same principle.
Posted: Wed Aug 27, 2008 9:49 pm
by zaskar98
Also when you compress a gas it actually heats up and becomes less dense, hence the use of an intercooler on a turboed engine to cool the compressed and heated air back down and increase the charge density. Any compression through the throttle body would be insufficient to cause a significant change in temp or density I would have thought, it's more about controlling total volume.
Posted: Wed Aug 27, 2008 10:19 pm
by I8A4RE
Also when you compress a gas it actually heats up and becomes less dense, hence the use of an intercooler on a turboed engine to cool the compressed and heated air back down and increase the charge density
No the intercooler is to cool down the air because its heated from the exhaust side of the turbo not by being compressed
Any compression through the throttle body would be insufficient to cause a significant change in temp or density
Agreed
Posted: Wed Aug 27, 2008 10:50 pm
by zaskar98
When you compress a gas it does heat up, as the space between the molecules gets smaller, their movement (Brownian motion) becomes faster and this causes a rise in temp; for example think of a diesel engine where huge compression causes the fuel/air mixture to heat to the point of reaching it's flash point and you get compression ignition. I agree that there will also be heat transfer in the turbo from exhaust gasses.
Also did you ever notice how the end of a bike pump gets hot when pumping up the tyres, this is also from the compression of the air in the pump, especially with road bike tyres which usually operate at over 100psi, less so with MTB usually around 50-70psi
Posted: Thu Aug 28, 2008 1:11 am
by zuihoujueding
so back to the topic please. what do you think about the product?
Posted: Thu Aug 28, 2008 8:42 am
by Bennoz
Short answer is mate, know one knows

We've not seen the product before, be a pioneer!
Posted: Thu Aug 28, 2008 9:14 am
by I8A4RE
zaskar98 wrote:When you compress a gas it does heat up, as the space between the molecules gets smaller, their movement (Brownian motion) becomes faster and this causes a rise in temp; for example think of a diesel engine where huge compression causes the fuel/air mixture to heat to the point of reaching it's flash point and you get compression ignition. I agree that there will also be heat transfer in the turbo from exhaust gasses.
Also did you ever notice how the end of a bike pump gets hot when pumping up the tyres, this is also from the compression of the air in the pump, especially with road bike tyres which usually operate at over 100psi, less so with MTB usually around 50-70psi
I NEVER said it doesnt heat up, i said thats not what an intercooler is for. Tell me which engines run with 100psi running through them

We are talking about engines not bicycle tyres

Re: air intake
Posted: Thu Aug 28, 2008 9:46 am
by Taeivon_Rep
Hey man i bought that kitt all it turns out to be is a section of straight metal pipe thats like 10cm long which fits into the pod fine but does not fit onto stock piping u actually gotta put the filter over the stock piping and clamp it down!!!
Doesn't improve performance made my gpx slower but damn it was loud.
Posted: Thu Aug 28, 2008 10:07 am
by zuihoujueding
thanks for the feedback taeivon_Rep!!!
you have a picture to share with us?
Posted: Thu Aug 28, 2008 11:46 pm
by zaskar98

Sorry, got a bit pedantic and carried away, think my choice of avatar is having a strange effect on me
