Rebel Ram said:
I have been following this thread with interest. I am still running a stock HY on my 01 since the turbo I got from an unnamed HACK was a dismal failure. (money down the toilet) Fortunately it was not any of the more popular turbo venders seen or talked about here.
I am running BD Jammer IIIs, An Edge Comp Drag, ATS ex manifold and a Banks high ram and 4" ex Brake.
I am concerned about a comment made about exceeding 35# of boost with PDRs HX-35 because I'm already there with the HY. That being so, I am looking for a turbo that will give me the performance that my engine needs while still being able to use my ex brake and not adversely effect daily drivability.
I hope this is inline with the discussion and staying on topic. Still watching.
The HY and HX35 turbos are very different.
The HX has a larger turbine, thus it can flow more on the exhaust side. The HX has turbine housings available from 12cm all the way to 21cm, thus you can tune it some.
The HX will deliver lower EGT for the same boost pressure from slightly lower drive pressure (larger turbine again)
ALL HX35 hybrids use the same turbine and turbine shaft. This is the same shaft that is on a HX40. The HX40 has a larger turbine than a HX35, thus when pushed hard, the added torque on the shaft can do damage to it.
Now to the hybrids, I have a HX40 from PDR, it has the same compressor wheel as their PDR35, but I am pushing my turbo to 38PSI at the manifold (46 at the compressor discharge).
Is it efficient at that high of boost? No, there are not many turbos this size that are. But it is very responsive at lower engine RPM.
Turbos are give and take, if you want one that spools well, you need an aggressive wheel that will move lots of air at low turbo RPM. You will sacrifice some top end efficiency with this, but you will end up with a turbo that is much more responsive and fun to drive.
A long time ago, I had a HY35 hybrid built with one of the smaller HX40 wheels (the 8 blade 59mm one) It spooled crazy fast, but after 2400 RPM it nosed over from high drive pressure.
When you are picking a turbo, pick the highest continuous power level you want to support. By continuous, I mean pulling a grade at the highest EGT you are comfortable with with the heaviest load you will every want to carry.
For most "sane" people this is close to 350 HP any more than that, you are acting stupid.
Both the PDR35, and the DZ35 will support this power level at 35 psi of boost, it's just that the DZ35 has to spin faster to do it and this added RPM adds to lag.