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Good point. Its gotta provide enough pressure to spool the turbo. Think about this: hold a pinwheel in front of your face and take a deep breath. If you exhale with your mouth wide open, pinwheel does nothing. You just open it a bit and exhale, pinwheel spins.
That is because you are exhaling into an open environment. With the turbo neck though its still a closed environment so the losses are very little in comparison.

Opening up the exhaust port will help with flow on the top end. It will decrease velocity slightly until it necks down into the turbo but I don't imagine it will have that much effect on spool as compared to moving to a larger turbo would.
 

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Really hope you guys find a great chunk of power
 

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I'm just glad I live close to you guys. I'm fairly new to NJ and hadn't had a clue where to go until you guys showed up here..

You can put me on the list for one of those heads
 
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I've seen a few more pictures than these and had my fingers in that exhaust port so I'll put a few things into perspective. The intake ports are barely wider than a nickel. This isnt really a bad thing and I dont see the size being a problem, mostly some tweaking for flow. The exhaust passages inside the head feel HUGE compared that that tiny rear port. If you laid eyes on the GTX manifold, you'll notice its a rather large circle. There should be NO problem opening up the head to port match it. The port matching alone will be a big benefit and will provide a lot more flow without impacting velocity as the very poor port match up is likely causing a ton of turbulence. Also the exducer on the k03 is about the size of a quarter. So even if you have a 3 inch exhaust... its all coming from a hole half the size an economy civic exhaust. The k03 inducer manifold tightens down to a very small hole to get the high velocity for a quick spool. The stock ports are simply not designed for the bigger turbos that need a lot more exhaust flow and I'm pretty sure after all the dynos and vdynos and different turbo combinations tried there is a strong consensis that there is and excessive constriction in the pre turbo exhaust. Im not sure if there are plans to port for the K03 as well but there will have to be specific port configurations for the different turbo "manifolds" being used right now.
 

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I've seen a few more pictures than these and had my fingers in that exhaust port so I'll put a few things into perspective. The intake ports are barely wider than a nickel. This isnt really a bad thing and I dont see the size being a problem, mostly some tweaking for flow. The exhaust passages inside the head feel HUGE compared that that tiny rear port. If you laid eyes on the GTX manifold, you'll notice its a rather large circle. There should be NO problem opening up the head to port match it. The port matching alone will be a big benefit and will provide a lot more flow without impacting velocity as the very poor port match up is likely causing a ton of turbulence. Also the exducer on the k03 is about the size of a quarter. So even if you have a 3 inch exhaust... its all coming from a hole half the size an economy civic exhaust. The k03 inducer manifold tightens down to a very small hole to get the high velocity for a quick spool. The stock ports are simply not designed for the bigger turbos that need a lot more exhaust flow and I'm pretty sure after all the dynos and vdynos and different turbo combinations tried there is a strong consensis that there is and excessive constriction in the pre turbo exhaust. Im not sure if there are plans to port for the K03 as well but there will have to be specific port configurations for the different turbo "manifolds" being used right now.
So what would you get from porting on the k03? Lower velocity exhaust flow and more power to come on in the upper RPM range?
 

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well you're always going to find some optimization of power but the K03 doesnt suffer from the same limitations as BT setups. im sure stable power over the 300hp threshold is possible but the K03 has no trouble making torque in ins optimal islands and pushing it in the higher rpm is an uphill battle against heat caused by trying to operate outside its efficiency range. But this is all my perspective. Only testing can show the truth.
 

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Discussion Starter · #30 ·
It would be awesome to see the integrated manifold disappear all together, and have studs and a tubular one adapted in its place.. I guess a man can dream
you mean like running an NA head on a boosted motor?

i wonder who's experimenting with that? :big smile:
 

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They could have done it to restrict power on purpose though. May have helped them stay in a higher MPG area, expand life of parts, etc. But who knows?
this would make sense, they dont want a focus that can compete with a 5.0 mustang. I believe all companies design their tiers of cars like this on purpose to sell specific cars to specific groups of people. imagine what could happen if you the mazda miata could be slightly altered and get 500HP... no one would ever my a mustang, rx8, or anything else in that range. so they build the entire car to max out much lower than that even with extreme modding. that is life, now lets find a way around this brick wall!!!
 

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Wonder if there is enough material/strength to cut off the headifold, weld up any coolant passages, insert some studs, and then mount a manifold.

Lots of work there, and the casting may not be able to handle that. Which means we would be dependent on an aftermarket head. Which would probably provide significant gains anyways.

I love ported heads, heads so ported you have add material. :)

 

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Wonder if there is enough material/strength to cut off the headifold, weld up any coolant passages, insert some studs, and then mount a manifold.

Lots of work there, and the casting may not be able to handle that. Which means we would be dependent on an aftermarket head. Which would probably provide significant gains anyways.

I love ported heads, heads so ported you have add material. :)

Like has been stated in this thread and I have said it in numerous other threads. You do not need to mill off the headifold and custom make an exhaust outlet, the NA head does not have the headifold design, and on top of that the 2.0EB that Jaguar uses and Land Rover uses in the Evoque do not have the headifold they use the NA head.
 
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