341 is a bigger turbo than a hx35 without issue. The exhaust housing is setup for a bit faster spool but on a gas motor it wont hurt your power much. I wouldnt expect less than 500whp out of one on good fuel.
Try to track down Matt Hawkins. He was a member here not long ago that built a turbo 3.4L TDC engine. Matt claimed his engine generated 400+ HP. AFAIK, Matt's engine remarkably stayed together at that power level but he blew up a few GETRAGS. This was before the F23 became popular.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I'm going to assume you mean HY35W Type D. The compressor numbers look good, not all that different than a GT3582R like I'm running, which is more or less ideal. Overall, its just a touch smaller than the GT3582R. But that means its drivability will be very good.
I'd opt for an A/R ratio on the turbine housing in the .8 ish range. Otherwise you'll start to cut into how much power you could make, and if you go into the 1.XX range, it'll be a little slower spooling, but get better at full boost. .8 A/R will get you great road manners and spool pretty quickly.
The only reason on saying you probably mean the HY35, is because the HE341 is actually very hard to come by and VERY expensive. Most people have a HY35W Type D and mistake it for a HE341 because the discharge is front facing. Most people sell them claiming they are HE341's. At least, that's what I read.
Rods seem to be good up to 400, maybe 450 ish, but this is coming from a guy that just broke an undetermined bottom end part, probably in the mid 400's horsepower on a 3.4 DOHC. I'll devulge the damage when I get to it.