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Re: Home made MBC-set up correctly?

Can't really say how it would last, but Andy Bowles was running boost way past the red line (the end of the gauge!!!) during the Southern Meet... Couldn't hardly believe my eyes.
But it did feel fast.
Nick.
 

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I believe Andy's was an Abbott Trionic mod. Like my Maptun box, which also boosts well beyond the red, you can bet it's winding the ignition back loads and dumping gallons (imperial gallons at that!) of fuel in under knock conditions - anything to avoid touching the boost.

Don't know how much the DI/APC/LH can cope with knock without boost control. Naturally, it'll be a "98+ RON only" job. At least my Maptun box will stand 95 RON in an emergency, although Maptun tell me that after two tankfulls of 95 in succession, it will have adapted so negatively that the only thing to do will be to disconnect/reconnect the battery and start from scratch.

Paul, I think the "quicker" feeling will be due to quicker spool-up as you keep the wastegate closed for longer. It'll be interesting to see how you get on. And of course, to see whether you can resist the temptation to keep edging the boost upwards until you find the limit of the piston-tops

Go for it
 

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MBC?. pls clarify.[/b]
MBC = Manual Boost Controller. Simply a device with which you manually set the max boost at which your turbo will run. This is as opposed to the Trionic or APC systems which electronically control boost according to the level of fuel available. Doing it manually you can set the level at whatever point you think your engine can safely cope before knock sets in. Manual devices work by holding air back from the wastegate so it doesn't know you've gone beyond the system's pre-set limit. That limit is usually on the conservative side so it is thought there is a margin for playing around.
 

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I am trying to be sensible....I opened too far to begin with....3/4 red....scary scary scary. But my god was it fast. Then I was a good lad!Turned it way down!
I think I have it set at pretty much stock...as bill said, the apparent performance increase could be faster spool up. I think a couple of Carly (stock) owners have said they get 1/2 red boost?

I have the MBC in the W-Hose...will this not keep (some) knock detection? I only use Optimax now...and I will decide whether to keep the MBC for quiet Sunday drives....

anyway, for £2, it was a good afternoon if nothing else!...............
 

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I had a Dawes device (MBC) on my 2.0L Carlsson, initially set around 21psi peaking off the red section of the gauge - yep it was fast but thought I'd wind in back. Ended up at mid red which according to my calibrated gauge was 15 to 16 psi. I ran that for over 5k miles without any problems I know off - car awaiting scrapping (still) as I dont think I'll get much for a 225k miles car with rotting door bottoms and no seats!
 
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