PDR HX40 Efficiency Range?

[C. Harlan]

What is the safe operating range for the PDR HX40?? I am just curious, especially since last time I dyno'd, and laid down ~35 HP less than before. . I had adjusted my wastegate back in March, and feel this may have something to do with it as well. Any input would be appreciated!



-Chris-

 

[SEmerson]

I have been told 40 psi

 

[Cooker]

37-38 PSI seems to be the peak at where you want to run an HX40.

 

[Forrest Nearing]

at what hp level? the hx4o maps I've seen were still on the map at 45psi... now as horsepower (air mass) goes to the right side of the map, the efficient pressure range begins to come DOWN

 

[Chipstien]

I agree with Forrest. I seem to remember that 44 was the max.

 

[C. Harlan]

So when I peg the go pedal and reach 44, is that still safe, or is that pushing it?? Just asking, because before I adjusted the Wastegate arm, I was seeing 44 psi, now down to 40. Do y'all think that may be the cause I was 35 HP low on the dyno charts as well???



-Chris-

 

[nfox]

PDR 40

When i installed mine Piers told me no more than 38psi of boost.

 

[Forrest Nearing]

could be... same dyno? same weather conditions? if so, you might want to crank it back up... I run mine at 42psi



Forrest

 

[Cooker]

Personally I do not think a 40 will live long if pushed past 40PSI on a regular basis. JMHO

 

[Forrest]

I ran my stock 40 for 5 yrs or so ... wastegated to 40psi.

 

[SEmerson]

I just set mine to 41 today. I was shooting for 40. Piers told me 38-39.

 

[Forrest Nearing]

Originally posted by Cooker

Personally I do not think a 40 will live long if pushed past 40PSI on a regular basis. JMHO

why not?



Forrest

 

[Cooker]

Originally posted by Forrest Nearing

why not?

Because everyone I have spoke with in the performance and turbo industry, Piers included, had made a statement similar to that. Not to mention I have know a handful of people to pop 40's pushing the limits above 40PSI.

 

[JR2]

When i installed mine Piers told me no more than 38psi of boost.

That is what he told me too. I have seen 40 psi once but I normally see 37-39 psi.



The plain and simple fact is that over 40 psi and your turbo is living on borrowed time. More than one guy on the boards has huffed an HX40 running more than 40 psi. If you need more than that, its upgrade time.

 

[Forrest Nearing]

Originally posted by JR2

That is what he told me too. I have seen 40 psi once but I normally see 37-39 psi.



The plain and simple fact is that over 40 psi and your turbo is living on borrowed time. More than one guy on the boards has huffed an HX40 running more than 40 psi. If you need more than that, its upgrade time.

more than one guy has run their HX40 at over 40psi with no problems...



I contend it's in driving style... the holset maps show the HX40 efficient into the 45psi range.



aftermarket vendors want their product to carry a good reputation of reliability, so they'll make very safe recomendations...



if you're drag racing with a manual transmission, and you let off at full boost all the time, keep the boost down...



if you're concious of the 40's shaft weakness and drive accordingly, I think you can make one live in the 40-45 range for a long time.



Forrest

 

[Diesel Freak]

38 at the inlet plenum = 44 at the turbo!



get the picture?

 

[Diesel Freak]

Originally posted by Forrest Nearing

the holset maps show the HX40 efficient into the 45psi range.



aftermarket vendors want their product to carry a good reputation of reliability, so they'll make very safe recomendations...



if you're drag racing with a manual transmission, and you let off at full boost all the time, keep the boost down...



if you're concious of the 40's shaft weakness and drive accordingly, I think you can make one live in the 40-45 range for a long time.



Forrest

See my previous post.



Driving style has a lot to do with turbo life. Roll into and out of the fuel.



If you are seeing over 44 psi of boost at the plenum, back it down to under 40 PSI.

 

[Forrest Nearing]

Originally posted by Diesel Freak

38 at the inlet plenum = 44 at the turbo!



get the picture?

good point, I haven't experamented with what kind of pressure drop these trucks see. that seems excessive, but...

 

[CATCRACKER]

diesel freak good info!! kind of like egt pre and post turbo readings.

 

[Fueler]

Originally posted by Diesel Freak

38 at the inlet plenum = 44 at the turbo!



get the picture?

so if im reading boost right in the air horn at 34psi... ... what would you say it is at the turbo?? im running dd3's with a comp and still on the stock hx35. before i bought an adjustable wastegate i was seeing 45+ psi. im in the market for a turbo right now and was still thinking of a 40/35 hybrid.