I have a HTB2 62/71/14cm turbo. It's set for 35 psi max boost. Lately when I hammer on it in levels 4&5 or if I'm pulling my camper, I get a bad chatter and a bark once in awhile. I've been told that my drive pressure may be too long. Or that I'm putting too much fuel in it.
Any suggetions??

 

Low drive pressure is what I meants to say. Anyone???

 

Is it below 2k rpm when this happens? Sounds like compressor surge. Normally not an issue with a 71mm turbine, not that I've ever had. Are you sure its a 71mm turbine, not possibly a 65mm? I went to HTT's site, talk about a lack of info on the turbo. I thought they'd come further in the past couple years.

 

Thanks for the reply. Yes, as far as I know, it is a 71mm turbine. And yes, it is below 2k RPM when it happens. Any ideas as to how to remedy this? Max pressure right now is set to 36.

 

Looser turbine housing, larger turbine wheel, higher rpm's, another turbo underneath. I'd be very suspicious of it actually being a 71mm wheel though. I've run a 62/71/0.80 and a 64/71/0.80, and I never surged with either of them. I went for a ride in Lil Dog's truck, whose fueling is less than mine, had a 62/65/0.70, and it surged something fierce. Ended up needing a rebuild in fairly short order.

 

Let me think.... Yep, it's a 71

 

I've had the same problem with mine and everyone questions and doubts the size of the turbo. The best "temporary" solution I've found is more rpm's. While it's happening drop down into drive and it instantly disappears with the higher rpm's. The general consensus is that it's hard on the turbo but no one has a permanent solution. I'd be interested in any info you find that helps alleviate the problem.