Boost Issues

[JustinStone]

Purchased a diablo intune i3 8345, and put a tune on the Cruiser. The boost wasn't making the numbers advertised, and talked about on forums, so I got to tinkering. The stock SRT4 wastegate opened with the slightest pressure to it, so about a .25" shim was added to stiffen the spring. This allowed for 2 more pounds of sustained boost but i still have an issue. My boost spikes at 13-14psi around 1-4k rpm, then begins to rapidly fall as I increase in speed, reaching as low as 7psi. An audible whooshing sound is heard, much like the blow-off, around 7-14psi while still on the throttle. Stock SRT4 BOV's are supposed to take upwards of 20psi so this failure doesn't make sense to me (I replaced the BOV with a spare and no change).

Does anyone have any suggestions?

Boost leak tests aren't impossible with our equipment, just a pain in the *** since the engine bay is tighter than spandex; so I'm tryna save some trouble.

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[JustinStone]

Similar, yet probably unrelated topic. The turbo flutter I had, has disappeared. I understand that flutter is surge, and the BOV is to reduce this, but tbh I was a fan. A 45mm turbo should despool for a good while, so the disappearance of it, especially with 2-4 more psi, has me concerned.

 

[THATpurpleKUSH 5,000+ posts]

This is a car audio forum not srt forum. You wont get much help on here.

 

[sherwood71]

Check all your cold side piping and couplers. Sounds like you might have a tear in a coupler.