Overboost diode question

[workedb6]

I have done a lot of searching and can not find anything about whether or not the diode will affect the way the car is supposed to run if you are tuned to make over the 17 psi a 4.7 diode sets you at. For me I have the Frankenturbo tune from unitronic and constantly see overboost codes with out ever getting near the boost the 24 pounds of boost I have read the turbo is supposed to make. I believe the problem is coming from the turbo spooling too fast even though I have lowered the pressure on the wastegate. Will running 24 pounds of boost at max be safe with the 17pound diode or will that force the car to run lean even though maf is seeing all the air.

[jvitelli17]

well the diode correct me if im wrong will allow the turbo to spool over 19? you need to get an mbc to manage the boost. not sure if u could get a larger diode to fool the MAP to build more. but my buddies a4 has the 4.7 and he is locked at 16 psi because he has a k03 but if we changed the mbc setting we could boost more.

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[workedb6]

I can easily make 24 pounds out of the turbo with my mbc because the tune cuts out limp mode. My problem is that I still get the check engine light. Im just afraid that if I put the diode in that the car will only see 17 pounds of boost and cut fuel making me run lean.

[jvitelli17]

well yes if the car thinks there is 17 psi of boost but u have 24, the ecm will only supply fuel for 17psi. I think more/less a custom tune is what u need. diode mod is good for those wanting 12-17 psi on stock tune but not when u wanna boost that high.

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[workedb6]

Im tuned with unitrinic stage 2+ frankenturbo and still see the overboost

[texasboy21]

Im tuned with unitrinic stage 2+ frankenturbo and still see the overboost

Your Franken turbo's wastegate crack pressure is higher than the K04s crack pressure that the tune was written for resulting in your overboost condition.

Rather than rigging up a diode, MBC, etc. just set the wastegate pressure to what the K04-015 runs. (7psi I think, dont quote me on that).

[workedb6]

Your Franken turbo's wastegate crack pressure is higher than the K04s crack pressure that the tune was written for resulting in your overboost condition.

Rather than rigging up a diode, MBC, etc. just set the wastegate pressure to what the K04-015 runs. (7psi I think, dont quote me on that).

I already have it set to just five to be safe