Number of bends in air pipe versus performance?

[Jaco Versfeld]

Hi There,

I have a quick question. Will the number of bends (90 degree) in the air pipe influence the performance of the engine? I was looking at mine, and the air filter already introduces 2 x 90 degree bends. If the bends do restrict the airflow, wouldn't it make sense to do a mod where the airfilter's outlet is nearer to the intake of the throttle body? If you could turn the filter around, the outlet would be nearer and you could elimininate the 2x90 degree bends.

[ThysdJ]

I guess if you are hunting that extra .01 sec on a quartermile that would be something you would seriously look at, but in the Hilux scheme of things, I dont think it has such a big influence. Yes, it is true, "less is more" and the more bends the more turbulence and restriction on the flow, but you wont really feel a big difference. You can also increase the ID of the pipe and the bends.

[LoneRanger]

The other thing is that a staight pipe would increace in the noise factor as well - the sound now runs direct instead of being bounced around - consider your silencer - the air goes into the front section the gets squeesed into a pipe that leads to the middle and the then again and then out! so if you want performance ...... get rid of the silencers :D

[Mr_B]

The intake manifold on a 4Y is so restrictive, that it doesn't really matter to much how many twists and turns come before it!

The important thing is just not to use ribbed air pipe, as it acts as a major air flow restrictor and generates alot of unwanted turbulence... rather use piping with a smooth inner wall!

mr b

[Sifu-Lux]

If you have a look at modern engines with variable geometry intake manifolds, you will see that when the engine revs are low, with a lower demand for air (say under 3000 RPM) the variable geometry intake runner is switched to a longer intake length, which increases the velocity of the incoming air charge and results in increased torque at lower RPM's.

As the revs rise, and the engine sucks more air, the variable geometry intake runner is switched to utilise the shorter intake runner which allows a higher volume of air with less restriction to the flow allowing for greater power to be developed (more air + more fuel).

For the Hilux with the 4Y/22R and even the Ford V6 which are not rev happy motors in standard form, a long smooth intake runner with as few bends as possible would be the best.

Airfilter direct on the carb with no runner creates very turbulent flow and reduced torque due to the low velocity, turbulent air flow. Not what you want with an offroad vehicle.

[Jaco Versfeld]

Thanks everyone.

Here is a picture of my setup. Would it be a case of "krap waar dit nie jeuk nie" if I modify the air filter housing. In the photo you cannot clearly see the 2 bends in the metal outlet from the filter. If I rotate the filter so that the back is in the front, the outlet will then align better with the throttle body.

What are your thoughts - should I rather use the money and tile the lounge - (will make my wife happy...)

Kind Regards,
Jaco

[andrew doherty 90]

I think, if ur worried about costs and if it will make much difference, you can do an intake made of pvc pipe (storm water pipe) and attach a pod filter or other aftermarket filter.
You can then increase the diameter of ur intake aswell. The main downside is it usually looks cheap and cr@!.
But turning ur filter box around could be easier, depending on the mounting brackets.

[BenHur]

Jaco

I removed the pipe on the dyno to see if it made a change in your performance and it did not make a difference at all if I removed the pipe, so there goes Bretton's theory about the restrictive aircleaner and ribbed pipe as well.

Some engines like Riaan's Oupa actually loses performance if you remove the restriction.

SO far the only vehicle we had on the dyno that we had to change piping on was Marius's Rooiwyn with the 3RZ mouter on the SFA and the guys used some plumbing that belonged to the origional 3L's turbo conversion and was less then 50mm ID on the one bend. Removed it and put ribbed sleeve on, increased the top en by 10HP on the dyno.

So yes tile Swambo's lounge rather

[BenHur]

I think, if ur worried about costs and if it will make much difference, you can do an intake made of pvc pipe (storm water pipe) and attach a pod filter or other aftermarket filter.
You can then increase the diameter of ur intake aswell. The main downside is it usually looks cheap and cr@!.
But turning ur filter box around could be easier, depending on the mounting brackets.

Said it many times before on this forum after market cone filters on a 4x4 is a no no, only good to filter out stones, birds and small pedestrians, dust go straight through it, PVC will not withstand the heat it will become soft and deform.

[DOELLOOS]

I guess if you are hunting that extra .01 sec on a quartermile that would be something you would seriously look at:twisted:

Just check how straight the air intake pipe on the Interceptor is...

[BenHur]

Yes very effective it will only allow 1 Cubic Inches of sand stones and insects through with every 5 Cubic Inches of air.

[DOELLOOS]

Jissie, maar that is effective!!!! I thought it was a 1 to 1 ratio...

[King Rat]

Tak, moenie stry nie, wat weet jy

[BenHur]

Jissie, maar that is effective!!!! I thought it was a 1 to 1 ratio...

But if you secure the the pan properly on the carb so that it does not such in air past the ambrella ag I mean air cleaner, the ratio becomes 1:1

[Mr_B]

Jaco

I removed the pipe on the dyno to see if it made a change in your performance and it did not make a difference at all if I removed the pipe, so there goes Bretton's theory about the restrictive aircleaner and ribbed pipe as well.

Yes yes... wise man... go read my post... firstly I never mentioned the aircleaner... according to people more knowledgeable than me... the intake manifold on a 4Y is the issue, so therefore ribbed vs smooth wall pipe(of the same internal diameter) has little or no effect on engine power... hence your correct deductions on the dyno...

dankie...
thank you...

[LouisZ]

Cone filters let dust in like nothing. My Silver Lux had one and after 1 month I had to replace it.

[CasKru]

If you maybe want that 1 to 5kw more on a 4y / 22R you should rather concentrate on the exhaust side. Get some heat insulation tape and tape up the exhaust manifold. This will increase the heat in the pipe making it less dense and gets out of the system faster. It also has a cooling effect on the air temp in the engine bay which will also help with performance as cooler air is denser air.

[DOELLOOS]

I will look into this...

[CasKru]

Moenie te diep kyk nie... it might be a scam

[DOELLOOS]

Funny guy, I kill you last....

[CasKru]

Funny guy, I kill you last....

:wth: :wth: :wth: :wth: :wth:

[BenHur]

point is Jaco's 4y is as good as it will get on a stock cam end head, time for tiling now