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Holset PRO 52 turbo

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Greaseable u-joints.

Remote fuel filter mount on frame rail

Jim Fulmer said:
EDIT: Could this new Super 40 be *the* top charger of choice in a twins combo???



Hum... ..... I'd be more than willing to test one :D



Jim



I would like for you to test one Jim :) I would be surprised if in a compound turbo situation if there would acutally be a noticable difference between the two, other than maybe a touch faster spoolup. JMHO I'd be real curious to see if you pick up any HP.
 
another dumb question

Idaho CTD said:
The PRO 52 shows it's on the map to around 4. 2 PR. If that is the case then running past 45psi (4. 16PR) would result in less flow and higher air temps. I guess 62psi (5. 36PR) is a little too far off the map to live very long. That's 29% higher PR then Holsets map says to run it to.



How did you do the math to get those or did you just assume that at 45psi the pressure ratio would be 4. 16pr or is there some kind of formula you follow?
 
BManis said:
How did you do the math to get those or did you just assume that at 45psi the pressure ratio would be 4. 16pr or is there some kind of formula you follow?

Ultimate pressure (equal to boost pressure + atmospheric pressure) / atmospheric pressure = pressure ratio



Atmospheric pressure at sea level is 14. 7 psi.



Someone correct me if I'm wrong.



-Scott
 
SRadke said:
Ultimate pressure (equal to boost pressure + atmospheric pressure) / atmospheric pressure = pressure ratio



Atmospheric pressure at sea level is 14. 7 psi.



Someone correct me if I'm wrong.



-Scott





Scott,



Your right but I didn't use 14. 7 because I assumed higher then sea level as most of us are higher.



Nathan
 
I'd like to correct a few items in this thread. The Super40 and Pro52 Holset turbos are available from any Holset Distributor. These turbos were developed to be out of the box ready for your Dodge Ram - meaning no internal mods necessary. These turbos are high speed balanced from the plant. The Pro52 does require some exhaust mods as it has a 4. 5 inch turbine outlet with a half marmon flange (flat). The Super40 has a 4 inch outlet with a full marmon flange (beveled) so depending on what brand downpipe you have you might have to machine the turbine outlet flange flat to accept your current downpipe. Both turbos have a 16cm turbine housing. The super40 is wastegated but the Pro52 is not. Max rotor speed for the 40 is 130,000 and for the 52 it is 112,000. Who else knows how to turbo the Dodge Ram besides the company that builds the engine. Holset is a division of Cummins.



Regards,

Holset Turbochargers
 
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Part numbers

By the way, the part numbers are as follows:

Super40 -- 4027888

Pro52 -- 4027895

Pro52 adapter -- 4038822



Another item of interest, if you have an 03-early04 Dodge with the HY turbo and 3" exhaust (stock) you can use part number 4035657 to go to a full 4" from the turbo. This is the exhaust elbow for the 04. 5 - 05 Cummins 600. It is available from any Holset Distributor as well.



Regards,

Holset Turbochargers
 
Well I just installed my Pro-52 this weekend... asside from the annoying oil leak coming from the feed line (which BTW, dont try looking for metric fittings in Texas!), I fianllay got it sealed up with a home made fitting and O-ring set-up. . I still havent gone WOT with my Comp box on, but with it off, im seeing about 32 psi of boost (Don M' Mach 5's) and I was able to hang tight with a C5 the other day up to 110mph... Once I get my BOV installed and a higher psi boost guage, Im gonna try some WOT passes with my box on 5x5. .

I am very suprised at how well this turbo spools, its very smooth, but comes in quick and holds boost through a good part of the RPM range. . My EGTs with the box off max at about 1400* but drop off to around 1250*F once the boost is in full. .

Here is the compressor map from Holset #ad


Luckily, my old H2E had the same downpipe as the Pro-52, so the 3rd gen downpipe which HTT provided wasn't needed. . It does require an exhaust adapter to bolt up to the stock manifold however. .

I think this will be a good contender with some of the mild to medium twin turbo setups. .

I forgot to add, Paul at HTT makes it real easy to bolt this turbo on, he offers the manifold adapter ($115 i think) and downpipe ($125 with machining to fit). . All in all, I paid about $1580 for the whole setup, but I'll get $80 back cuz I dont need the downpipe adapter...
 
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Nice!! I wonder how they compare with the Garret GTP-38 BB turbo for PSD's, as far as performance, specs, capabilities, etc.
 
Oh shoot... ... yes that's a big advantage. Don't know how it got in my head that these new Holset's do as well. Maybe from all the talk about the ATS and DD turbo's. I've been away from the site for a little bit and guess I haven't caught up yet.



Trever
 
SRossi said:
Well I just installed my Pro-52 this weekend... asside from the annoying oil leak coming from the feed line (which BTW, dont try looking for metric fittings in Texas!), I fianllay got it sealed up with a home made fitting and O-ring set-up. . I still havent gone WOT with my Comp box on, but with it off, im seeing about 32 psi of boost (Don M' Mach 5's) and I was able to hang tight with a C5 the other day up to 110mph... Once I get my BOV installed and a higher psi boost guage, Im gonna try some WOT passes with my box on 5x5. .

I am very suprised at how well this turbo spools, its very smooth, but comes in quick and holds boost through a good part of the RPM range. . My EGTs with the box off max at about 1400* but drop off to around 1250*F once the boost is in full. .

Here is the compressor map from Holset #ad


Luckily, my old H2E had the same downpipe as the Pro-52, so the 3rd gen downpipe which HTT provided wasn't needed. . It does require an exhaust adapter to bolt up to the stock manifold however. .

I think this will be a good contender with some of the mild to medium twin turbo setups. .

I forgot to add, Paul at HTT makes it real easy to bolt this turbo on, he offers the manifold adapter ($115 i think) and downpipe ($125 with machining to fit). . All in all, I paid about $1580 for the whole setup, but I'll get $80 back cuz I dont need the downpipe adapter...





With the mach 5's where exacly in the rpm band does the turbo spool? (meaning when does ACTUAL boost rise occur?) With the box on 2x5? with the box off? Just really curious thats all. Thanks in advance.
 
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