Mbc/diode On 99 1.8?

[slopoke]

Ok so i have no intentions on keeping the stock k03 for more than a few months to save up for the eliminator, so i dont want to waste money on a chipped ecu. All the write-ups i have seen are on 01+ b5's due to the maf. So can i throw in a mbc and crank it up to 14-15psi so it moves out of its own damn way? Mods so far are 3" tp/neuspeed exhaust/modded air box. Thank you!

[ct1.8t4me]

On a 99 the most you'll safely get is about 10-11PSI - IF that. The nDBW ECU hits a HARD fuel cut-off when it shows lean from running "high" boost. What you basically get is a very hard and noticeable stutter as the ECU shuts off the fuel to the cylinders as an indicator - "HEY DUMMY you are going to blow me up."

Believe me, I went through extensive testing of different MBCs and approaches. Even tried a 5 BAR FPR just to be able to supply more fuel - the most I ever got was 10-11 PSI and that was not reliable at all. It was very dependent on temperature, when and how hard you hit the throttle...

So - for $50 or so for a cheap MBC - is it worth it? Depends...just be careful.

[ct1.8t4me]

BTW - the diode mod does not work on nDBW cars.

[slopoke]

ahh so stock is what 7-8psi?:and i could only get away with 9-10?

[slopoke]

so if i did get it chiiped(giac is local) and say spiked 19-20psi, what could i crank it up to?

[ct1.8t4me]

Yup - some folks have tweaked their chipped K03 up to 23 or so. I am having a hard time getting 20 reliably...

[mike-2ptzero]

Ok so i have no intentions on keeping the stock k03 for more than a few months to save up for the eliminator, so i dont want to waste money on a chipped ecu. All the write-ups i have seen are on 01+ b5's due to the maf. So can i throw in a mbc and crank it up to 14-15psi so it moves out of its own damn way? Mods so far are 3" tp/neuspeed exhaust/modded air box. Thank you!

Diode mod is for the MAP (AKA boost sensor) not for the maf.


BTW the Test pipe can cause the turbo to run at a lower boost pressure because the test pipe can cause less back pressure at the wg opening and it isn't like the ECU can adjust to run get the boost back up where it should be. Exhaust follows the path with the least resistance and the TP does decrease back pressure for both the turbo outlet and WG outlet at the same time.

[slopoke]

really my 3"tp on my last a4 with ko3/giac ecu/borla dropped my 1/8 mle time .5 sec! i thought that was a huge improvment! I went from 10.0-10.1 on a 82* day down to 9.6 consecutively and it was 97* that time!

[slopoke]

so basically i can only run about 2 more psi with out tunning? Will i even notice that?

[bass_lover1]

I've been running 11-12 psi with a boost controller safely for the last year or so.

My a/f ratio is perfect, never set off the CEL for a lean condition. I do however, recommend using a vag-com to check your timing retard under full throttle to make sure you aren't doing the motor any harm.

[slopoke]

Will a cheap $10 ebay one work fine? If go and spend $200 on a boost controller i might as well chip it and then sell the chip later on. Like this one is this fine?
http://cgi.ebay.com/ebaymotors/Manua...m170218899333&

[ExSRAaron]

so basically i can only run about 2 more psi with out tunning? Will i even notice that?

Normally its 1 psi = 10 hp...so maybe 20 extra horsepower. Noticable, but not really worth it IMO..buy some coilovers in the meantime and go nuts!

[slopoke]

Will those ebay ones work fine, or could they fail and send 3547249057320psi to my engine?

[bass_lover1]

Will a cheap $10 ebay one work fine? If go and spend $200 on a boost controller i might as well chip it and then sell the chip later on. Like this one is this fine?
http://cgi.ebay.com/ebaymotors/Manua...m170218899333&

It'll work, but you don't need something that complicated. Mine was made by Dawes...it might be Boost Factory now, but google it, should turn up.