Collapsing air intake pipe
12-30-06, 04:15 PM
#1
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Collapsing air intake pipe
Hi there,
I have heard that if the intake concertina pipes that run from the airbox to the turbos collapse, then they can cause obvious issues with restrictions to air flow to the turbos.
I have also read that if this happens, the increased vacuum that is caused can suck oil out of the turbos and into the air.
My question is: would anyone have any idea how much restriction to one of these pipes would be required to actually cause this oil suction effect? 10%, 20% .... 50% etc? (In otherwords, are the pipe diameters borderline for the volume of air needed at WOT and high revs, and if even a slight restriction is introduced, then you cause the above mentioned increase in vacuum and hence oil suction?)
Cheers!
I have heard that if the intake concertina pipes that run from the airbox to the turbos collapse, then they can cause obvious issues with restrictions to air flow to the turbos.
I have also read that if this happens, the increased vacuum that is caused can suck oil out of the turbos and into the air.
My question is: would anyone have any idea how much restriction to one of these pipes would be required to actually cause this oil suction effect? 10%, 20% .... 50% etc? (In otherwords, are the pipe diameters borderline for the volume of air needed at WOT and high revs, and if even a slight restriction is introduced, then you cause the above mentioned increase in vacuum and hence oil suction?)
Cheers!
12-30-06, 04:57 PM
#2
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Is the pipes collapsing a common problem? I've never heard of that. If you're worried about it, just buy some hard pipes off E-bay. I bought them for like 50 bucks. The 90 pipe from the primary didn't fit, but I still used the longer straighter one for the secondary. At least it looks better. But I'm about to buy the GReddy intake anyway, so doesn't matter any more.
12-30-06, 05:37 PM
#3
2/4 wheel cornering fiend
It's not a common problem, but it does happen, especially with old, weathered intake piping, and the somewhat restrictive stock intake crossover tube. In fact, it's that restrictive stock intake crossover that will cause the stock rubber tube to collapse more than its ID; the stock ID itself is more than sufficient for the stock twins, since it is basically the same size as the piping leading to the compressor inlet.
If you've got oil in the intake, it's probably more related to worn turbo shaft seals than any excessive vacuum caused by collapsing stock intake tubes.
If you've got oil in the intake, it's probably more related to worn turbo shaft seals than any excessive vacuum caused by collapsing stock intake tubes.
12-30-06, 08:13 PM
#4
You must ask the question: Why do they collapse? They collapse because the turbos are pulling so hard that they cannot get enough air. While this is very rare, it can happen. The best solution is to modify the stock airbox to flow more air. This will reduce the suction forces on the intake tubes to a much lower level.
Click the link in my sig for info on an inexpensive kit ($70) to modifly your stcok airbox.
Click the link in my sig for info on an inexpensive kit ($70) to modifly your stcok airbox.
