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It's Decided. 2.5 Turbo. Winter 2019

Wascally Wabbit1

Drag Racing Champion
I haven't looked too much into catch cans or how they work but if there is a valve on the bottom could you not feed it right back to the oil pan? or is the oil compromised in some way?

You will read about people doing this and I believe there is even a kit to route back to your oil dipstick tube. This is a terrible idea. The point of the catch can is to catch water vapor and the little oil droplets that ride along on this vapor.
Routing it back to the oil pan is far worse than not having it at all. You would be reintroducing the moisture back into the oil and it would contaminate the oil very quickly. People always say..."well the moisture was there in the first place so what's the difference?" You have to let that moisture out. Normally it goes through the PCV into the intake manifold and is burnt up in the hellspawn of fire that is your combustion chamber.

Here is a good artlicle on the subject.
https://www.mishimoto.com/engineering/2016/01/blow-by-101-what-is-blow-by

The other option is to vent to atmosphere but the problem with that is, besides being a federal crime here in the US, it allows pressure to build up in the crankcase causing excessive blowby and power loss. The other problem with venting to atmosphere is that it may not allow enough flow out of the valve cover and again foul the oil due to water contamination. There are a lot of factors in this though such as the climate you live in, the size and type of motor and so on. On my catch can set up I was getting about a 1/4 cup of water a week. I could easily see how if that were not allowed out the oil would be compromised pretty quick. Venting to ATM also makes a big oil mess of your engine bay. Some people vent it down to the ground but if you do that you should also get a new license plate that reads "IMADICK" or in my town "IH8THEC" or "DYDLFNS".... Sorry I was having fun with that. I live at the beach so dumping oil on the ground is akin to just walking down on the beach and pouring a quart of oil in the ocean every so often.

I have an APR can and think it's the best design out there but it's $400. I no longer use the can on the car as I don't think it is super necessary on a NA car but it may be more important with the turbo. Really the GTI and TDI are the cars it helps the most as they are direct injection cars so it prevents the carbon problems associated with direct injection.
 
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Wascally Wabbit1

Drag Racing Champion
In the future

IE Forged Rods (Lower compression)
IE SRI
Upgrade the blow off and Wastegate.
maybe a water/meth.
Unsure what I'll get the PSI up to after this

If your going this far I would highly recomend IE or APR valve springs get added to the list. Stiffer springs prevent valve float.
 

FlowMK6

Ready to race!
If it were an inline pump would the filter on the original pump not do it?
I never thought of a fuel regulator and to be honest don't even know a thing about them. Any tips? Also will I need a restrictor for the oil going to the turbo?

I haven't looked to much into catch cans or how they work but if there is a valve on the bottom could you not feed it right back to the oil pan? or is the oil compromised in some way?


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It's not a filter, it's a strainer, it's to protect the pump against debris, it doesn't act as a filter

You need a fuel pressure regulator since our car have a returnless fuel system, meaning the fuel regulator is part of the OEM filter. The reason you need to change to a return fuel system is because you need a variable fuel pressure depending of the boost

Our car use ported injection, it vaporize fuel into the intake manifold to mix it with air at atmospheric pressure (at WOT), the stock fuel pressure is around 45-50psi

If you boost 10psi under load, it's 10 more than atmospheric pressure, since pressure travel from higher to lowest, the boost inside the intake manifold will create restriction against injectors. In that case, the fuel pressure regulator will have to create restriction in the flow to create greater pressure (+10psi) which would give 55-60psi to match the boost

It's important to understand that the pump doesn't create pressure, it's just a pump that flow a liquid at a certain rate. When the fuel pressure regulator create restriction, it needs more pressure to pump the fluid at the same rate through the restriction

I don't think you will need an oil restrictor for the oil feed

As for the catch can, it's really a bad idea to recirculate into the oil pan. To better understand it, I will give some explanations

When an engine wear, the piston rings wear and they become less tight allowing vapors to pass through and reach the crankcase building excessive pressure in the crankcase. Therefore the need for a ventilation system to remove excess pressure and vent the contaminant at the same time (moisture, fuel vapor, etc..)

What you get in the catch can is oil vapor, humidity and fuel vapors, recirculating the content of the catch can into the oil pan would be the same thing than recirculating contaminants in your oil reducing the lifetime of it.

The main purpose of the catch can is to keep your engine cleaner, don't recirculate it into your oil :)


Edit: You don't need valvetrain work except if you want to rev over 7500 (near 7500rpm it starts to float). If it's something you are planning to do, I would recommend oversized Ferrera valves and titanium spring, but if you plan to rev over 7500, you will need to alter valve lift / duration with custom cams to keep torque at higher rpm, you can visit CatCams if it interests you, they make camshafts for our engine. I would do some head porting before playing with valvetrain
 
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OrangeSpy

Ready to race!
It's not a filter, it's a strainer, it's to protect the pump against debris, it doesn't act as a filter

You need a fuel pressure regulator since our car have a returnless fuel system, meaning the fuel regulator is part of the OEM filter. The reason you need to change to a return fuel system is because you need a variable fuel pressure depending of the boost

Our car use ported injection, it vaporize fuel into the intake manifold to mix it with air at atmospheric pressure (at WOT), the stock fuel pressure is around 45-50psi

If you boost 10psi under load, it's 10 more than atmospheric pressure, since pressure travel from higher to lowest, the boost inside the intake manifold will create restriction against injectors. In that case, the fuel pressure regulator will have to create restriction in the flow to create greater pressure (+10psi) which would give 55-60psi to match the boost

It's important to understand that the pump doesn't create pressure, it's just a pump that flow a liquid at a certain rate. When the fuel pressure regulator create restriction, it needs more pressure to pump the fluid at the same rate through the restriction

I don't think you will need an oil restrictor for the oil feed

As for the catch can, it's really a bad idea to recirculate into the oil pan. To better understand it, I will give some explanations

When an engine wear, the piston rings wear and they become less tight allowing vapors to pass through and reach the crankcase building excessive pressure in the crankcase. Therefore the need for a ventilation system to remove excess pressure and vent the contaminant at the same time (moisture, fuel vapor, etc..)

What you get in the catch can is oil vapor, humidity and fuel vapors, recirculating the content of the catch can into the oil pan would be the same thing than recirculating contaminants in your oil reducing the lifetime of it.

The main purpose of the catch can is to keep your engine cleaner, don't recirculate it into your oil :)


Edit: You don't need valvetrain work except if you want to rev over 7500 (near 7500rpm it starts to float). If it's something you are planning to do, I would recommend oversized Ferrera valves and titanium spring, but if you plan to rev over 7500, you will need to alter valve lift / duration with custom cams to keep torque at higher rpm, you can visit CatCams if it interests you, they make camshafts for our engine. I would do some head porting before playing with valvetrain
Thanks for the detail!
Could you point me in the direction of a regulator/Filter?
Is there certine types I need or an ideal restriction?

Sent from my SM-A520W using Tapatalk
 

OrangeSpy

Ready to race!
You will read about people doing this and I believe there is even a kit to route back to your oil dipstick tube. This is a terrible idea. The point of the catch can is to catch water vapor and the little oil droplets that ride along on this vapor and prevent it from entering your intake tract. Routing it back to the oil pan is far worse than not having it at all. You would be reintroducing the moisture back into the oil and it would contaminate the oil very quickly. People always say..."well the moisture was there in the first place so what's the difference?" You have to let that moisture out. Normally it goes through the PCV into the intake manifold and is burnt up in the hellspawn of fire that is your combustion chamber.

Here is a good artlicle on the subject.
https://www.mishimoto.com/engineering/2016/01/blow-by-101-what-is-blow-by

The other option is to vent to atmosphere but the problem with that is, besides being a federal crime here in the US, it allows pressure to build up in the crankcase causing excessive blowby and power loss. The other problem with venting to atmosphere is that it may not allow enough flow out of the valve cover and again foul the oil due to water contamination. There are a lot of factors in this though such as the climate you live in, the size and type of motor and so on. On my catch can set up I was getting about a 1/4 cup of water a week. I could easily see how if that were not allowed out the oil would be compromised pretty quick. Venting to ATM also makes a big oil mess of your engine bay. Some people vent it down to the ground but if you do that you should also get a new license plate that reads "IMADICK" or in my town "IH8THEC" or "DYDLFNS".... Sorry I was having fun with that. I live at the beach so dumping oil on the ground is akin to just walking down on the beach and pouring a quart of oil in the ocean every so often.

I have an APR can and think it's the best design out there but it's $400. I no longer use the can on the car as I don't think it is super necessary on a NA car but it may be more important with the turbo. Really the GTI and TDI are the cars it helps the most as they are direct injection cars so it prevents the carbon problems associated with direct injection.
That makes sense, thanks for all the detail I'm slowly put this all together haha

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FlowMK6

Ready to race!
Thanks for the detail!
Could you point me in the direction of a regulator/Filter?
Is there certine types I need or an ideal restriction?

Sent from my SM-A520W using Tapatalk

From friends and from what I have seen, you can't go wrong with Aeromotive fuel pressure regulator, I would put a gauge on it too

For the fuel filter, any inline fuel filter should do the job, take reputable brand and you shouldn't run into issues :)
 

OrangeSpy

Ready to race!
From friends and from what I have seen, you can't go wrong with Aeromotive fuel pressure regulator, I would put a gauge on it too

For the fuel filter, any inline fuel filter should do the job, take reputable brand and you shouldn't run into issues :)
Thanks! I see a lot of these are adjustable, how would I go about adjusting it for what I need?

Ive also been told that the injectors work as their own regulators by not allowing more then what their capable of (ie. 550cc Injectors will not surpass 550cc)
Thoughts?

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FlowMK6

Ready to race!
Thanks! I see a lot of these are adjustable, how would I go about adjusting it for what I need?

Ive also been told that the injectors work as their own regulators by not allowing more then what their capable of (ie. 550cc Injectors will not surpass 550cc)
Thoughts?

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What you are talking about is injector flow (550cc/min)

An injector is an ON/OFF and the ECU decide of the injected fuel quantity by varying the duty cycle. When a bigger injector pulse, there is more fuel injected than a pulse from a smaller injector, that's why you need to tune your car after upgrading to bigger injector, because the injected quantity for a pulse isn't the same as a stock injector

As for the pressure, all injector are mounted on a pressurized fuel rail and that pressure is made possible by the fuel pressure regulator

To adjust your fuel pressure regulator, you would have to adjust the static (base) pressure to the same as OEM (near 45-50psi). Then you would have a hose going from a bost port to your fuel regulator. If you boost 5psi, the fuel regulator would sum 5psi to your static setting (45-50psi) which would give 50-55psi. It's to compensate for the higher pressure in the manifold since it's a ported injection, otherwise it might have difficulty to vaporize and it's important to understand that liquid gasoline doesn't burn, it's gasoline in his vapor state that burn and it's exactly why winter gas differ from summer gas, the winter gas have to be more volatile
 

OrangeSpy

Ready to race!
Honestly guys thanks for all the detail and putting up with all my questions!
I just ordered the Turbo and will slowly buy parts throughout the year. Once I park the car for the winter (November or December) I'll send the ECU away and start the build!

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OrangeSpy

Ready to race!
In regards to the manifold

From what I can gather ill need longer bolts.

Does anyone know how long stock bolts are or how thick the manifold flange is?

Any suggestions how to get them out

edit: Exhaust Manifold
 
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MLue1

Drag Racing Champion
In regards to the manifold.
From what I can gather I'll need to put in longer manifold bolts.
Anyone have any idea how long stock ones are or how thick the stock manifold flange is?
Any suggestions on how to get the old bolts out?

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The intake manifold bolts are M6 bolts.
 

OrangeSpy

Ready to race!
The intake manifold bolts are M6 bolts.
Sorry I should have clarified haha Exhaust Manifold

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FlowMK6

Ready to race!
Exhaust stud is M8x38, I don't know the thread pitch, maybe 1.25

Part number for reference :
Exhaust stud N01444312
Exhaust nut N90894601
 
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OrangeSpy

Ready to race!
Exhaust stud is M8x38, I don't know the thread pitch, maybe 1.25

Part number for reference :
Exhaust stud N01444312
Exhaust nut N90894601
perfect thanks!

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