Trying to cure Boost drop off..

[Turbo Habanero]

So i've had this problem for who knows how long as i just decided recently to start turning up the boost.

As of right now my boost will hit 17.5psi (3rd gear pull from 40mph) and not hold that for even a second before falling slowly to 12.5-13psi by redline.

Any help or insight is welcome and appreciated.


Things i've checked and double checked

BOV is nice and tight
All IC pipes have great solid mounting surfaces and all T-Bolt clamps are Fastened correctly
Vacuum to Boost Gauge is nice and tight
Vacuum from turbo and waste gate to MBC are clamped
Checked all Vac sources through out engine (Insight on what one's would cause boost leaks would be help full)

My mods that relate to this Problem

CT26 60-1 with stock wastegate not Shimmed.
NXS MBC (EBAY) with about 5inch vacuum Lines http://www.ebay.com/itm/NXS-MANUAL-...es&hash=item3c9db9eeae&vxp=mtr#ht_1508wt_1061
Driftmotion Intercooler Kit with a Knock off Tial 50mm

Things that i think could be causing the issue.

20+ year old waste gate
or Cheapo MBC

 

[te72]

I know Turbosmart's more pricey EBC's suggest that they prevent high rpm boost drop off, but have no experience with them myself. Might be worth looking into.

 

[CyFi6]

I have the Turbosmart Eboost Street with the feature Brad was referring to with my 57 trim ct26, and it actually works fairly well. I used to spike and drop 3 or 4 psi by redline, but with this boost controller it still spikes a little but holds boost all the way to redline.

 

[airhead04]

Wastegate spring is old and tired man. That is one big factor right there. I have an extra one here if you want to try swapping it out.

 

[Turbo Habanero]

Thanks for the reply's guys.

Airhead let me know how much you want for it and to ship to 85742 Tucson AZ I Appreciate the help.

On a side note if I get this problem fixed I'm going to need some wider tires lol. I think the boost drop off helps me with traction in second

 

[airhead04]

Just cover shipping and its yours. Ill ship it out tomorrow and tell you how much. should be like 10 BUCKS TOPS.

 

[Turbo Habanero]

I get paid on Monday I would rather pay you for it but I Appreciate it tons.

Is there a way to rebuild the stock waste gate ? Does anyone have a link or any info or doing this? Is it as simple as replacing the springs ? I have no clue when it comes to our internal waste gates.

 

[airhead04]

I get paid on Monday I would rather pay you for it but I Appreciate it tons.

Is there a way to rebuild the stock waste gate ? Does anyone have a link or any info or doing this? Is it as simple as replacing the springs ? I have no clue when it comes to our internal waste gates.

No need to pay me man, I have like 4 of them. lol. Send me your address in a pm and I will get it out tomorrow for you. And I dont believe you can rebuild them. I think its a sealed unit. Dont quote me though! lol

 

[Turbo Habanero]

I wonder what a new one cost or if there is a aftermarket option available beside a external setup

 

[Compton74]

not to go off topic at all but great job with the intro post habanero, makes it so much easier to help identify and fix issues when you've already told us whats up! props to you