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Just found someone to port my wastegate, but he mentioned that you must have some sort of boost controller running to control boost levels. Has anyone ported and NOT used a boost controller?
 

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??? That doesnt make any sense. All you are doing (as long as you dont OVERPORT - causing leaks) is expanding the wastegate port, so that all the exhaust can flow out. If you make it bigger... psi would go down before it goes up.... I had to turn my SBC-ID spec 3 up because it wasnt overflowing and whatnot anymore. It runs 100x better now. You shouldnt need a boost controller as you #1 wont be overboosting, #2 you're gaining space and you're still flowing the same amount of exhaust so you shouldnt underboost... just make sure he does it right and doesnt overport (causing leakage). Good luck!

Robert~
 

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thats kinda wierd... well i dont see ap roblem or a reason for a boost controller, but *shrug* maybe it'd be worth it to go ahead and get one (just run stock boost if you wish).

Robert~
 

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hayasa said:
OK, but read this. This is why I was asking for a second opinion:

http://forums.nasioc.com/forums/showthread.php?s=&threadid=492988
This is why...


"I should add that you MUST have some form of boost control and a boost gauge since I'll be making your wastegate flow a lot more; the boost control solenoid's factory-programmed duty cycle curve will not be sufficient to reach full boost. All that is needed is a simple bleeder valve (like a TurboXS ABC), but an MBC or aftermarket EBC will also work great."

He is correct IMO, but I have no first hand experience. You are changing the flow of the wastegate but not the map that the ECM will reference to control boost.

-st
 

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staticx313 said:
??? That doesnt make any sense. All you are doing (as long as you dont OVERPORT - causing leaks) is expanding the wastegate port, so that all the exhaust can flow out. If you make it bigger... psi would go down before it goes up.... I had to turn my SBC-ID spec 3 up because it wasnt overflowing and whatnot anymore. It runs 100x better now. You shouldnt need a boost controller as you #1 wont be overboosting, #2 you're gaining space and you're still flowing the same amount of exhaust so you shouldnt underboost... just make sure he does it right and doesnt overport (causing leakage). Good luck!

Robert~
Yeah, that is actually what he is saying. You will need an aftermarket form of boost control to achieve stock boost levels after porting the wastegate.

-st
 

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Nope, not true. After my wastegate port, levels are back to stock. If the ECU monitors boost via a vaccum, it reads the amount of boost running in your car - hence that is how your ECU knows when to cut the fuel. If it has a specific preprogrammed map, it should be able to adjust the wastegate position from fully open to fully closed depending on the amount of boost it sees to fit the stock boost levels.

Now unless you port the wastegate so much that it's flow characteristics are beyond that of the stock map, you may have problems keeping the boost level up since the flow characteristics have changed drastically and will need a BC.

I'm not a car guru, but based on what I've researched and my own port job, needing a boost controller for a 'properly' ported wastegate isn't necessary.
 

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Evolution Performance Driving school in St. Louis

blueballs said:
Nope, not true. After my wastegate port, levels are back to stock. If the ECU monitors boost via a vaccum, it reads the amount of boost running in your car - hence that is how your ECU knows when to cut the fuel. If it has a specific preprogrammed map, it should be able to adjust the wastegate position from fully open to fully closed depending on the amount of boost it sees to fit the stock boost levels.

Now unless you port the wastegate so much that it's flow characteristics are beyond that of the stock map, you may have problems keeping the boost level up since the flow characteristics have changed drastically and will need a BC.

I'm not a car guru, but based on what I've researched and my own port job, needing a boost controller for a 'properly' ported wastegate isn't necessary.
Unless you've proven this by running the stock exhaust with a ported wastegate (that is what we are talking about here) I stand by my previous statement.

Most ECMs have static wastegate maps that cannot be altered except with a reflash of the map.

-st
 

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I have a TurboXS downpipe, racepipe to a 3" Borla Hushback. I have no personal experience for porting a wategate with the stock exhaust.

I still find it hard to believe and this is why. Whe I first had the exhaust installed, it was not too cold out. I usually go WOT everyday on the highway. As people know, the air temp. gets lower, the boost creep gets worse. Now even at a stock level, the ECU must have to read the amount of boost and vary the wastegate actuator depending on this because many factors will influence the amount of boost you get.

Now from my own personal experience. After the wastegate port on my catless setup, I have watched the boost gauge on a -10 degree day and a 36 degree day and noticed no change in the amount of boost I got. I am assuming the only reasoning behind this must be the ECU actively adjusts the wastegate in order to fit its programmed maps.

Well, if the ECU monitors factors like temp., load, throttle position, but does not monitor boost to controll the wastegate actuator, then how does the ECU know to cut the fuel when you've gone over 17.5 psi?

Maybe what he said is true for stock turbobacks for a number of reasons:
1-You were getting boost creep all along and now the boost is maintained at stock levels, hence it is lower.

2-Wastegate was overported and needs a BC to delay the opening of the wastegate to keep the boost up.

3-Why would you need to port the wastegate if you have a stock turboback anyway... 8)
 

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why are do our HIDs not look like HIDs.....

3 - you wouldn't, but you still might not keep the same boost levels because when the wastegate opens it's spilling off boost faster than the ECU map expects it too - meaning lower boost than stock.
 

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hayasa said:
Just found someone to port my wastegate, but he mentioned that you must have some sort of boost controller running to control boost levels. Has anyone ported and NOT used a boost controller?
You will want a controller anyway.

Are you going to spend all that money on nice mods, porting turbo, etc.. and not drop a few hundred to properly control your boost?

Plus, with an nice EBC you get:
1) Faster spool up = more whp (in low gears) & quicker whp (in high gears).
2) Ability to increase boost over stock level-(safely to 15.5).
3) More accurate controll of boost
4) Overboost warning features
5) Nice boost gauge to boot.

So, why wouldn't you want one?
 

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The boost solenoid map is a closed loop with feedback. A properly ported exhaust housing will not prevent the OEM control from reaching appropriate boost - without regard to exhaust mods. The solenoid will be open and the wastegate closed until the target feedback is reached. A freer flowing wastegate path does not reduce boost if the wastegate still closes properly. If a port is not reaching full boost under OEM control it is because the wastegate flapper is no longer is sealing completely - i.e. it was over ported.
 

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ChargedPerformance said:
The boost solenoid map is a closed loop with feedback. A properly ported exhaust housing will not prevent the OEM control from reaching appropriate boost - without regard to exhaust mods. The solenoid will be open and the wastegate closed until the target feedback is reached. A freer flowing wastegate path does not reduce boost if the wastegate still closes properly. If a port is not reaching full boost under OEM control it is because the wastegate flapper is no longer is sealing completely - i.e. it was over ported.
Thank you for the info.

-st
 

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Thanks chargedperfromance. That's what I wanted to convey. I wish I knew exactly how this feedback system worked. When boost solenoid sees Xpsi = open wastegate by X amount in what increments, etc..?

Lower boost in a ported housing tells you the wastegate was overported. One thing to remember is that the wastegate flapper moves around slightly so you must take that into account when porting. Do not just go by the ring of carbon deposits surrounding the sealing area of the wastegate.
 
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Deadbolt is very good, I know him personally, and recommend his work at every opportunity. I know a bunch of people who have been very satisfied with his product.
 

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bcinlas4, Ive heard good things about deadbolt....when i called they were very nice....XXTuning ports now in CT.I'm gettin ported(had to change my app) 03/10/04....and adding the blitz exhaust and will be dynoing the car...i want to see 300 at the wheels...wish me luck. Peace
 

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I've got a full Scoobysport (Hayward & Scott) system on order. I will also probably run the new Accuteck when it comes out.
 
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