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Turbo Inlet Pipe Comprehensive Thread
I. Introduction
II. Installation Guides
III. Technical Section
IV. Who makes a replacement?
V. Additional References
I. Introduction
The 90 degree bend that is at the entrance of your turbocharger. The piece is made of plastic and has a restrictive area in the bend. It looks similar to a metal pipe that is crush bent instead of mandrel bent. As a result, the diameter is not consistent all the way through... this produces a restriction on the inlet of the turbocharger.
This is NOT the same as the intake pipe. Intake pipes are made of silicon, either 4-ply or 5-ply.
II. Installation Guides
See the links below to guides that have already been created.
1. By Goingnowherefast on Golfmk7 http://www.golfmk7.com/forums/showthread.php?t=17696
2. By Deviation01 on Golfmk7 https://www.youtube.com/edit?o=U&video_id=lZd4ImJH-aA
III. Technical Section
A big debate is whether or not this actually has a perceivable benefit. I think (opinion only, since I have no data with flow/pressure) that the purpose of the CTS/Levo/VWR/etc. turbo inlet pipe is to reduce the restriction which reduces the pressure drop.
This in turn will shift you towards the higher efficiency zone of the turbo.
http://www.golfmk6.com/forums/showthread.php?t=18432
Grambles on the golfmk6 forum does a very good job explaining things.
The two links below are for an article by Garrett and Stratified's explanation on some of the things that Garrett posted/created.
https://www.turbobygarrett.com/turbo...bo_tech_expert
http://stratifiedauto.com/blog/a-tec...turbocharging/
Because a turbocharger adds pressure... the higher you can get the inlet of the turbocharger, the more pressure it makes. If air enters the turbocharger at 0 psi and the turbocharger makes 20 psi... you output 20 psi. If the air enters at 14.7 psi and the turbo makes 20 psi... you output 34.7 psi.
Taking into account the intercooler pressure drops... if you have the stock intercooler (let's just say pressure drop of 5 psi) you'll go from 34.7 to 29.7 going into the engine. Going to an aftermarket where the intercooler has say a 2 psi drop... the pressure entering the engine would be 32.7 psi.
From anecdotal evidence (no flow numbers and no compressor curve available), I believe that these Turbo Inlet Pipes are just to reduce the pressure drop. Evidence by people who say the turbocharger seems to spool earlier/at lower RPMs is evidence of this.
Since our wastegates are electronically controlled, the ECU will limit the manifold pressure of the turbocharger to OEM boost setting. When you tune, part of the tune (aside from fueling, timing, etc.) is the boost setting. By reducing pressure drops on the inlet of the turbocharger, you help shift the compressor into a high efficiency zone where increasing the boost will give you more wiggle room before you are in a very inefficient zone (see the references posted above).
IV. Who makes a replacement?
1. CTS Turbo
Mandrel bent aluminum with CNC'ed flanges.
2. Leyo Motorsports
Mandrel bent aluminum with CNC'ed flanges. Benefit is that the flange that connects to the inlet hose is the same as the OEM.
3. VWR
Glossy black instead of the grainy powder coated black on CTS and Leyo Motorsports.
4. Spulen
Has 2 metal (aluminum?) CNC'ed adapters connected by silicone.
5. Turbo Technic Turbo Inlet Pipe (elbow) and Intake Pipe
Has been dynoed by Regal Autosport with just the APR stage 1 tune (golf R) and this part added power that you would see with an intake. Of course... this could also be within the error tolerance.
6. BMS
Very similar to the CTS, VWR, and Leyo turbo inlet pipe. The only notable difference is that there is no lip like in the CTS and VWR one. Versus the Leyo one, it does not have a sectioned lip like the Leyo and OEM turbo inlet pipe.
7. MST
Expands up to 3" and comes with a silicone replacement tube.
8. APR
Has smooth transitions.
V. Other Reference
1. http://www.vwroc.com/forums/topic/13015-best-turbo-inlet-hose/page-4
2. http://www.golfmk7.com/forums/showthread.php?t=15893
3. http://www.golfmk7.com/forums/showthread.php?p=412441#post412441
4. http://www.golfmk7.com/forums/showthread.php?t=27549 (see post #14)
5. http://www.mygolfmk7.com/2018/09/turbocharger-inlet-pipe-airflow-test/ Has testing done by benchflow showing effects of the OEM turbo inlet pipe.
I. Introduction
II. Installation Guides
III. Technical Section
IV. Who makes a replacement?
V. Additional References
I. Introduction
The 90 degree bend that is at the entrance of your turbocharger. The piece is made of plastic and has a restrictive area in the bend. It looks similar to a metal pipe that is crush bent instead of mandrel bent. As a result, the diameter is not consistent all the way through... this produces a restriction on the inlet of the turbocharger.
This is NOT the same as the intake pipe. Intake pipes are made of silicon, either 4-ply or 5-ply.
Image above is taken from the CTS Turbo website and shows the elimination of the restriction.
CTS Turbo Inlet Pipe next to stock inlet pipe. Image taken from a post by MK7VW on GolfMK7.
II. Installation Guides
See the links below to guides that have already been created.
1. By Goingnowherefast on Golfmk7 http://www.golfmk7.com/forums/showthread.php?t=17696
2. By Deviation01 on Golfmk7 https://www.youtube.com/edit?o=U&video_id=lZd4ImJH-aA
III. Technical Section
A big debate is whether or not this actually has a perceivable benefit. I think (opinion only, since I have no data with flow/pressure) that the purpose of the CTS/Levo/VWR/etc. turbo inlet pipe is to reduce the restriction which reduces the pressure drop.
This in turn will shift you towards the higher efficiency zone of the turbo.
http://www.golfmk6.com/forums/showthread.php?t=18432
Grambles on the golfmk6 forum does a very good job explaining things.
The two links below are for an article by Garrett and Stratified's explanation on some of the things that Garrett posted/created.
https://www.turbobygarrett.com/turbo...bo_tech_expert
http://stratifiedauto.com/blog/a-tec...turbocharging/
Because a turbocharger adds pressure... the higher you can get the inlet of the turbocharger, the more pressure it makes. If air enters the turbocharger at 0 psi and the turbocharger makes 20 psi... you output 20 psi. If the air enters at 14.7 psi and the turbo makes 20 psi... you output 34.7 psi.
Taking into account the intercooler pressure drops... if you have the stock intercooler (let's just say pressure drop of 5 psi) you'll go from 34.7 to 29.7 going into the engine. Going to an aftermarket where the intercooler has say a 2 psi drop... the pressure entering the engine would be 32.7 psi.
From anecdotal evidence (no flow numbers and no compressor curve available), I believe that these Turbo Inlet Pipes are just to reduce the pressure drop. Evidence by people who say the turbocharger seems to spool earlier/at lower RPMs is evidence of this.
Since our wastegates are electronically controlled, the ECU will limit the manifold pressure of the turbocharger to OEM boost setting. When you tune, part of the tune (aside from fueling, timing, etc.) is the boost setting. By reducing pressure drops on the inlet of the turbocharger, you help shift the compressor into a high efficiency zone where increasing the boost will give you more wiggle room before you are in a very inefficient zone (see the references posted above).
IV. Who makes a replacement?
1. CTS Turbo
Mandrel bent aluminum with CNC'ed flanges.
2. Leyo Motorsports
Mandrel bent aluminum with CNC'ed flanges. Benefit is that the flange that connects to the inlet hose is the same as the OEM.
3. VWR
Glossy black instead of the grainy powder coated black on CTS and Leyo Motorsports.
4. Spulen
Has 2 metal (aluminum?) CNC'ed adapters connected by silicone.
5. Turbo Technic Turbo Inlet Pipe (elbow) and Intake Pipe
Has been dynoed by Regal Autosport with just the APR stage 1 tune (golf R) and this part added power that you would see with an intake. Of course... this could also be within the error tolerance.
6. BMS
Very similar to the CTS, VWR, and Leyo turbo inlet pipe. The only notable difference is that there is no lip like in the CTS and VWR one. Versus the Leyo one, it does not have a sectioned lip like the Leyo and OEM turbo inlet pipe.
7. MST
Expands up to 3" and comes with a silicone replacement tube.
8. APR
Has smooth transitions.
V. Other Reference
1. http://www.vwroc.com/forums/topic/13015-best-turbo-inlet-hose/page-4
2. http://www.golfmk7.com/forums/showthread.php?t=15893
3. http://www.golfmk7.com/forums/showthread.php?p=412441#post412441
4. http://www.golfmk7.com/forums/showthread.php?t=27549 (see post #14)
5. http://www.mygolfmk7.com/2018/09/turbocharger-inlet-pipe-airflow-test/ Has testing done by benchflow showing effects of the OEM turbo inlet pipe.
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