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Discussion Starter · #1 ·
Guys,

Does anyone know a bypass for the different boost settings in each gear.

I'm a bit apprehensive about installing a MBC on my car as its a brand spanker.

But I would prefer if I could run full boost in all gears!

Is the ECU using a Speedsensor input or is there a 'which gear' input to the ECU?

I'm pretty sure an MBC will void my warranty but if all I have to do is unplug wire 'X' to change this it would be great!

Cheers
Antony
 

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The easiest way to bypass the stock boost controller is to put in a boost controller. I don't think there is any way to trick the ECU into thinking it is in a different gear which is what the Hayabusa drag racers used to do. In my opinion messing with the ECU is riskier than putting a boost controller anyway. A manual boost controller can be swapped out in ten minutes or less. Spend $48 and put in a Joe P. You won't regret it.

-Jim
 

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Word of warning MBC = $2-$60
EBC = $200-$600

If you have the cash, I'd go for the Electronic boost controller since you can (dependant on model of EBC) adjust the amount of boost by either gear or throttle position. Both accomplish the same thing (more boost by bypassing the ECUs control) With the EBC you probably won't have to buy a boost gauge either (a MUST with a MBC!) since it's built in.
 

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EBC's are great.... but if your looking to be stealth..... an EBC isn't the easiest thing to hide from a dealer.... whereas you can disconnect your MBC in about 10 minutes like Platinum said....

Depends what you want to do.....
 

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Discussion Starter · #7 ·
Guys,

Thanks for all the replies.

I spose a MBC will do the job. But I'm a bit apprehensive.

But what I was hoping for was to retain the stock factory boost behaviour of reduced boost at higher revs.

Basically I want the boost/fuel map that I get in 3rd gear now in all gears not just 3rd and above.

If I install a MBC the wife will kill me should anything go wrong!!!!

I thought if it snipped a wire or put in a resistor or whatever and got what I wanted noone would know the different and it would be running a factory boost/fuel map.

Cheers
AntMan
 

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just put in the mbc and set it at 14.5 or 15 psi. that way you'll have higher boost in the lower gears (insteat of maxed at 9psi), and the same boost in the upper gears. a lot of people are doing that.


dR
 

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Kenneth2000 said:
EBC's are great.... but if your looking to be stealth..... an EBC isn't the easiest thing to hide from a dealer.... whereas you can disconnect your MBC in about 10 minutes like Platinum said....
That is incorrect. I just need to disconnect the hoses, one clip and one bolt to take out my SBC-id selenoid. Easy as cake to do. My dealer thought it was some kind of navigation system anyway.
Antman, you do not want to reduce boost at high RPM at all but guess what? You will no matter what. The stock turbo is so tiny it can't keep up and will do it naturally no matter what boost setting you use. Why do you want to do that anyway? :confused:
 

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Discussion Starter · #10 ·
God,

What I want to do is basically take the fuel map / boost map for 3rd gear and have it work in 1st and 2nd gears.

I don't want to increase boost above the factory 14.7psi.
And I also don't want the car to hold boost longer than it does from the factory. Which I understand is an effect of the MBC.

Also using the MBC set at stock boost of 14.7psi would mean the car would be running with 14.7psi boost with a fuel map designed for 9psi of boost when in first gear wouldn't it or are the fuel maps the same but just reduced boost?

I just want to run full boost in first and second gears!

If I can't beat someone off the line in first and second gears theres no point going for third!

Cheers
AntMan
 

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What I want to do is basically take the fuel map / boost map for 3rd gear and have it work in 1st and 2nd gears.

Maps are not gear dependant as far as fuel/timing is concerend. So as long as you're running the same boost you'll have the same map, regardless of what gear you are in.

I don't want to increase boost above the factory 14.7psi.
And I also don't want the car to hold boost longer than it does from the factory. Which I understand is an effect of the MBC.

Why not? It makes a big difference. Don't want the car to hold boost longer? Why not? I don't understand this part. No matter where you set your boost controller your turbo dies out and you drop to around 13-14 PSI at redline anyway. Just set to 16 PSI and forget about it. You'll be very happy and your turbo will not be working much harder than it already is.
 

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Discussion Starter · #12 ·
God,

Just a few questions:

1. If the ECU doens't know what gear you are in they how can it know to limit boost in 1st and 2nd gears?

2. WIll holding boost longer cause the car to lean out?

3. Does a MBC cause speed creep at partial throttle openings?

When it comes down to it I'm not chasing extra ponies over the stock output I just want my 160kw available in every gear not just 3rd and above.

Thanks for all your help!

Cheers
AntMan
 

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1. If the ECU doens't know what gear you are in they how can it know to limit boost in 1st and 2nd gears?

I never said the ECU doesn't know. It does, which is how it limits boost BUT the spark and timing maps are the same. They are not speed dependant.

2. WIll holding boost longer cause the car to lean out?

Not at all. In fact the car runs super rich across the board stock.

3. Does a MBC cause speed creep at partial throttle openings?

Speed creep or boost creep? As far as boost creep, I have heard of people complaining about full boost at partial throttle with MBC's but since I have never installed, used or endorse MBC's I have no idea. It is not a problem with electronic controllers at all. I can not get this to happen in my car and I have tried many times in all gears. Then again I have a PE1818F so its a bit different. This is not really boost creep though. Boost creep is when you get higher boost in 4th or 5th gear from increased load. A litle is normal, too much is dangerous.
 
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