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Old 11-05-2010, 12:21 AM   #81
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so wait how do you securely connect a barb fitting to a 1/16" thick aluminum pipe?
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Old 11-05-2010, 12:42 AM   #82
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weld on bung... lots of rtv gasket maker? lol
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Old 11-05-2010, 12:50 AM   #83
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Old 11-05-2010, 10:14 AM   #84
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Sorry if this question has been asked. But, if you tap the cold side as opposed to tapping the compressor housing, there may be a significant downside - If the charge piping leaks or you pop a coupler... then the turbo will be overextended because the tap will always be reporting a low pressure right?
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Old 11-05-2010, 11:24 AM   #85
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Quote:
Originally Posted by 05pearl View Post
Sorry if this question has been asked. But, if you tap the cold side as opposed to tapping the compressor housing, there may be a significant downside - If the charge piping leaks or you pop a coupler... then the turbo will be overextended because the tap will always be reporting a low pressure right?
It would depend on the size of the leak. If you have a leak at the charge pipe directly after the compressor, even if you had it tapped at the compressor housing you could argue that it would over spin the turbo.

If you pop a coupler off I would hope to hell you would let off the gas.
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Old 11-05-2010, 12:22 PM   #86
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^True. Once you felt a lack of boost, you would let off the gas. So, there is not much of chance of overspinning. Just trying to sort this out before giving it a shot.

Last edited by 05pearl; 11-05-2010 at 12:33 PM.
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Old 11-05-2010, 05:32 PM   #87
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Tapping the compressor vs on the TB side and having a coupler break loose will be the same result as the boost goes less than 2 psi in both ways and the wastegate will shut closed putting all the exhaust gasses through the turbo charger anyways. The wastegate is made to open at what you have it set at usually over 6 psi, which is much greater than what an open air turbo can create.

Last edited by triple88a; 11-05-2010 at 05:53 PM.
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Old 12-10-2010, 06:03 PM   #88
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Has anyone tapped there EBC into the throttle body itself but before the butterfly? It seems to be nice and thick and I could get the fitting in better there than a thin 1mm pipe.
From the statements above the EBC needs to go after the IC but before the tb and so by that I would guess the butterfly of the tb.

If I tapped it this high up is that going to cause me problems?

Do you lose out on any boost by tapping at the cold side of the IC to the pipe which goes onto the tb. Is there that much if any difference?
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Old 12-10-2010, 06:11 PM   #89
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As stated above, the general assumption is that the feed line to the boost controller should be before the throttle body.
I would like a statement concerning this.

Why before the throttle body?
I've put mine at the 4th runner, and it works like a charm.
(Just to make it clear, the topic is discussable, and I've heard positives and negatives concerning both placements)
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Old 12-10-2010, 06:22 PM   #90
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The pre-TB placement is for MBC only. EBC doesn't care.
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Old 12-10-2010, 06:28 PM   #91
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So EBC can go on the inlet manifold after the TB? Is it not the same principle where it will detect the wrong boost if it isnt before the TB?
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Old 12-10-2010, 06:37 PM   #92
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I'm using a MBC. What is the difference?
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Old 12-10-2010, 07:03 PM   #93
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Any boost controller after the throttle body is bad. The 4th runner = trouble. The difference is that in the 4th runner, or any spot in your intake manifold to be exact, you're cruising with 60-70 mph, 3.5-4krpm. You're in vacuum and thats what the boost controller is seeing so the waste gate is 100% closed. That turbo is spoolin 20-25 psi in the intake piping when you only want it to spool max of let say 12 psi. You stomp on the gas and you get a boost spike at 15-20 psi for a sec.
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Old 12-10-2010, 07:11 PM   #94
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So, while the TB is open, there's a large difference in pressure at either side?
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Old 12-10-2010, 07:15 PM   #95
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Quote:
Originally Posted by ronniebiggs View Post
Do you lose out on any boost by tapping at the cold side of the IC to the pipe which goes onto the tb. Is there that much if any difference?
You shouldn't lose any. If you are seeing a measurable pressure differential across the piece of pipe which connects the intercooler to the throttle then something is very wrong with your plumbing.



Quote:
Originally Posted by Loki79 View Post
Why before the throttle body?
Go back and read Post #15 in this thread.




Quote:
Originally Posted by ronniebiggs View Post
So EBC can go on the inlet manifold after the TB? Is it not the same principle where it will detect the wrong boost if it isnt before the TB?
Personally, I don't like the idea of taking the sample from a point after the throttle body on a street car, regardless of whether EBC or MBC is employed.

A lot of folks running EBC are taking advantage of the EBC functionality which is integrated into their ECU, and in these situations it is unavoidable that the pressure reference is taken post-TB, as that's where the ECU's MAP sensor is connected.

I will posit that with conscientious tuning, an EBC system can be made to run safely and efficiently with a post-TB reference. Essentially, this requires the use of a 2-axis boost targets table, which takes TPS into account to lower (or eliminate) the boost target at low throttle conditions. The Megasquirt provides this capability, and some folks here have configured it in this manner.

I simply fail to see the benefit of increasing the complexity of the system in this way.
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Old 12-10-2010, 07:23 PM   #96
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Quote:
Originally Posted by Loki79 View Post
So, while the TB is open, there's a large difference in pressure at either side?
Yes, one side is at vac, other side is at psi. I'm assuming you are cruising and not at idle. Its just like a water hose. One side is high pressure other side is low and the faucet is what is separating.
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Old 12-10-2010, 07:24 PM   #97
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Quote:
Originally Posted by Joe Perez View Post
You shouldn't lose any. If you are seeing a measurable pressure differential across the piece of pipe which connects the intercooler to the throttle then something is very wrong with your plumbing.



Go back and read Post #15 in this thread.




Personally, I don't like the idea of taking the sample from a point after the throttle body on a street car, regardless of whether EBC or MBC is employed.

A lot of folks running EBC are taking advantage of the EBC functionality which is integrated into their ECU, and in these situations it is unavoidable that the pressure reference is taken post-TB, as that's where the ECU's MAP sensor is connected.

I will posit that with conscientious tuning, an EBC system can be made to run safely and efficiently with a post-TB reference. Essentially, this requires the use of a 2-axis boost targets table, which takes TPS into account to lower (or eliminate) the boost target at low throttle conditions. The Megasquirt provides this capability, and some folks here have configured it in this manner.

I simply fail to see the benefit of increasing the complexity of the system in this way.
forgive me but im a bit fo a noob when it comes to this topic but is what you are saying that it is still best to fit an EBC before the TB instead of after to avoid complicating matters further?

I have a MS but need to keep things simple at this point as im still in the process of learning the basics.

Thanks for the help
Andy
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Old 12-10-2010, 07:30 PM   #98
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Quote:
Originally Posted by ronniebiggs View Post
forgive me but im a bit fo a noob when it comes to this topic but is what you are saying that it is still best to fit an EBC before the TB instead of after to avoid complicating matters further?
Personally, I think it's best to fit an MBC and call it a day.

I'm not saying that there's anything wrong with the concept of EBC, or even that you can't make EBC work properly even with a post-TB reference. Plenty of folks here have done it.

I just feel that installing a ball-and-spring MBC of reasonable quality, with a reference taken post-IC and pre-TB, is far simpler to implement and tune, and will provide equivalent performance.
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Old 12-10-2010, 07:33 PM   #99
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Quote:
Originally Posted by Joe Perez View Post
and will provide equivalent performance.
For fraction of the cost if the ebc is purchased.
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Old 12-13-2010, 06:19 AM   #100
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Quote:
Originally Posted by triple88a View Post
Yes, one side is at vac, other side is at psi. I'm assuming you are cruising and not at idle. Its just like a water hose. One side is high pressure other side is low and the faucet is what is separating.
Big thanks to you and Perez, this post along with #15 made it very clear

After I moved my signal hose to the 4th runner, the engine is using about 2l of fuel pr 10km. Could this be the reason? This is a massive increase from earlier, but I thought it was only due to the increase in pressure and lack of tuning at that part of my fuel table.

My mapping at the extra boost pressure is off, but even on cruising speed at ~0 psi she still drinks like a drunk englishman.
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