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Discussion Starter · #1 ·
mbc vs ebc

okay wich one is better?

I know I asked this before but never really ever got a specific answer so i promise this will be the last time...

anyway I know the joe p is like on 50 bucks buts lets say money is not a issue for minute eaven though it is...:rolleyes:

is there a diff between the mbc and the ebc besides having the ability to change boost right in front of you're face instead of going under hood..??

is the ebc just for lazy guys and good looks...?? or is there more to an ebc that I dont know about...??? and what is the best ebc for the wrx and what would it cost.?
 

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Does a MBC cause partial thottle overboost (and higher EGTs)?

This topic has come up on i-club and been brought to my attention in personal messages from clubwrx.net members. Some claim that a MBC can generate full boost from the turbocharger at partial throttle. Further more, these people claim that this condition leads to higher exhaust gas temperatures (EGT).

This belief stems from a lack of understanding about how a turbocharger operates and I assure all clubwrx members that as long as you don't set your MBC too high (above 17psi) you won't have any problems.

I have been running the Joe P MBC since my car had less than 5,000 miles on it. Since then I have done several long trips where a lot of partial throttle was involved. I have no problems with my car at all with my boost gauge reading 16.5 psi at WOT in fourth and fifth. I'm running my boost to max for the stock turbo on my daily driver and I have yet to see an issue.

Here's why partial throttle isn't a problem with a MBC:
A turbo can only develop boost at high engine speeds and large intake and exhaust flow. It cannot attain maximum boost at partial throttle BECAUSE it is at partial throttle. The MBC gives the turbo it's boost limit, it doesn't cause it to create more boost. That would be a thermodynamic impossibility.

As for higher EGTs, this has some reason to it. When a car runs rich it has lower EGTs. When a car runs lean it has higher EGTs. When a turbocharged car it at partial throttle, it receives more air than a NA car because it has forced induction. The ECU only supply the fuel it needs to maintain power. This can lead to slightly higher EGTs, but it is nothing to worry about.

IMO, this all got started because someone was trying to justify spending $400 for an EBC instead of $50 for a MBC. For those that want and can afford an EBC, go for it. I'm just saying that a MBC in the right hands won't harm your precious 2.0L flat four.

Happy boosting, all.

-Jim
 

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------------------------------------

"is there a diff between the mbc and the ebc besides having the ability to change boost right in front of you're face instead of going under hood..?? "

"is the ebc just for lazy guys and good looks...?? or is there more to an ebc that I dont know about...??? and what is the best ebc for the wrx and what would it cost.?

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An EBC from Blitz can cost between $300 and $400. Good ones allow you to adjust the boost for each gear and from the cockpit and, yeah, they're pretty. A dual solenoid EBC will allow for very accurate boost control for quicker spool up and finer full boost hold. They are also a little harder to install. The MBC takes 5 minutes for a pro to install and a couple of minutes of driving to dial in.

Is an EBC worth the extra money, maybe, but then, I'm running 13s without adjusting my boost EVER on my Joe P MBC and I drive my car to work every single day. I might add a dual solenoid unit later, but it will be in the interest of better highway fuel mileage by opening my wastegate a little earlier in fifth gear.

If you want electronic boost control and tons of power, same your money and put it towards a better ECU.

-Jim
 

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I prefer the electronic. It provides better boost response and better control with some neat features on some units. A manual one gets the job done but the convenience of a boost controller at your fingertips is fantastic. I never use manual controllers at all ever.
 

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Hey god,

do you notice higher EGT's with your EBC at part throttle? Just wondering considering that people with MBC seem to be experiencing this.


thanks,
ryan
 

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Discussion Starter · #8 ·
thanks for all the 'input guys i have decided to just go with the joe p mbc for now..and after i modify the car some more in the very near future i will then add a ebc...Thanks again for all the help.
 

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God, does it mean using a EBC will eliminates or redues the part throttle/full boost condition associated with MBC. I seem to come across this issue from this board and i-club.

btw glad to hear your baby is back in good shape.
 

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Gas milage

What kind of a difference in gas milage do you see when using a boost controller over pure stock? How about a mbc vs. ebc?


Karl
 

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:confused:

OK, so are ppl on i-club just imagining high p-t EGTs? Is something else causing it? I wouldn't think they were lying about their EGTs, but you can always question the diagnosis. Do you have an EGT guage Plat? If so, where did you put the probe? Also, the clamp on probes...are they as accurate as a drilled-in probe? One more question...can you hook up an EBC so that you can turn it off and run off the stock ECU? (and not just the 9psi of the wastegate spring)?

TIA

VV
 

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The WRX comes with a EGT probe in the uppipe. If anything got out of hand, the CEL would've come on by now. The peeps at i-club aren't imagining higher EGTs, but the higher EGTs are NORMAL, as I explained above. I don't have a gauge yet, but it will simply connect to the stock EGT sensor and read its voltage. If you switch off an EBC, it will run the 9psi wastegate spring pressure. If you take it off and put the stock vaccum hoses back in, it will return to stock. You could also rig up a control solenoid, like the TurboXS dual boost controller uses, to switch between the two using an electrical relay.

-Jim
 

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a bit off topic here,

but I posted a reply twice in here. did you moderators delete it?


ryan
 
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