those of running this turbo, who has surge problems. what exactly does surging feel like? is it that bad? looking to by a turbo soon and want to make the right decision if surging is a issue ; what size exhaust housing are you running?

 

SuperPhatShaft66, a little bigger than the sledpuller66's hotside (or so I hear). It basically makes a "chuff chuff chuff" when you let off at high boost levels. On mine, 60psi, you let off quickly, and you see the boost drop from 60, hit 45 and bounce around, then drop to 30 and bounce around. It makes a "chuff" sound. It's not a problem towing or anything. It only happens over 30psi at 1,600rpm.

 

If you're going to tow, you'll have plenty of surge problems with the HT66. The 62 is worlds better for towing. The PS66 also appears to be better.

The "bark" you hear when suddenly letting off the throttle isn't necessarily the same as surging, even though there's a bark during surge. Surging happens usually at low to mid throttle settings. Pulling a hill with a load, at slight throttle, for example. As you're going up the hill, the turbo will begin to build boost which also brings on more fuel and power, which builds still more boost. You let up on the throttle, just a little, to keep speed steady, the boost drops along with fuel, power drops, and you have to slightly apply throttle to get it back. Then the cycle starts over again. You can't drive with a steady throttle because it becomes overly sensitive. At certain throttle settings and rpm ranges, surge can be very difficult, if not impossible, to control.