I can hear my turbo going, ch ch ch ch when I'm in 5th gear accelerating. What is it?? Is it bad??? How do I make it go away????

93, 16cm housing, pump tweaked supposedly, 4 inch exhaust off the turbo, no guages....

 

do a search on turbo flutter

 

It sounds to me like the turbo (compressor side) is surging. It's caused by the turbo being driven to produce too much boost with too little air flow. An increase in RPM's should stop it.

Also, Map Width Enhancement is designed to widen the compressor map of a turbo to prevent surging. Scroll down to "Surge Line" on this page for a more complete description:
http://www.turbobygarrett.com/turbob...o_tech103.html

Any of HTT's compressor upgrades (Stage I through IV) offer ported shroud compressor housings (same as Map Width Enhancement). Also, an HX35 is a common upgrade for 1st gens that also offers MWE.

Compressor surge is hard on the turbo's shaft. I'd avoid it if possible, or upgrade the compressor if money permits.

 

I love my HX35!! Makes for a different truck. Hardest part of the swap was scraping off the old turbo drain gasket! Best of all, no more "woof...woof...woof"!

 

Try the HTT Stage III upgrade, it cures the bark and it screams like a 747 on takeoff.