I got this delivered to my office today. Goes on one of my 2.5 ton or 5 ton trucks.

 

is it for diesel?

 

Yes, but I don't see why we couldn't make it work on "other" applications.
Its not mine though. Its the Army's.

 

I know a lot of Mustang guys that use Holsett turbos for their cars, in fact the HP engineering kits come with Holsett turbos. That anti-surge compressor housing makes them absolutely SCREAM when they spool up.

 

I have a holset being installed on my car. If you do a search in this forum, you will find a few people running them.

 

that housing is an anti surge right? why would a diesel need anti surge housing if it doesnt have tb plates? and is it for some kinda tug or what.

 

That looks like the H1E. I've made 417 RWHP off the wastegate spring (1Bar) and a moderate tune. I'll be bringing BDC back to Portland SOON to crank the boost up to about 25psi with some race gas! Then we'll compare my #'s with some other setups

 

This is not an expensive turbo either. Price on the box indicated around $540.

 

it's unbelievable how loud those anti-surge housings can be.

 

Your jaw might drop if you knew the price of mines Also, this is the imfamous SRMotorsports stage II turbo. I know this for a fact because I bought one.

 

Klar,

whats the NSN on that? was it ordered through a GSA contract? or a sole source purchase. reason I ask is that often time suppliers will often times sell items for the same price to military members providing its not a controlled item good example would be a 40 mm he grenade for the 203, but you can buy the standard 5.56 round useing the same NSN as the military and they will sell at the ssame reduced price.

something to think about.

kenn

 

Those aren't "anti-surge" housings based on what I've been told by a turbo assembler guy -- they're noise-reduction to get rid of the "whoosh" sounds that are driving the truckers (who drive hours on end) nuts.

That's a nice unit.. T4 based, decent-sized shaft.. can't go wrong.

B

 

Seems like it. Here is my (custom spec KKK ) SR turbo, looks just like Klars.



I can tell you one thing, it's not working on my car . This turbo whistles like crazy. Makes my car sound like a semi. My friend can hear my turbo over the sound of his T04S when we are both driving together.

 

That IS a anti-surge housing. And anti-surge housings DO make more noise then a standard bell mouthed inlet housing.

Some diesels need the anti-surge housings because the turbo's are sized so spool up is quick (keep in mind diesels have like a 3500~4800 rev limit, so there power band is small) and the turbo can pump more air then the engine is willing to injest till it reaches a higher rpm, therefore the turbo can be in surge. Surge is simply the turbo pumping more air then the engine is willing to injest, be it a turbo too big for an engine, or the turbo making boost too quickly and then engine cant take it all in till the rpms climb, or a throttle slamed shut.

~Mike...........

 

cool, thats good to know.

 

Are you sure about that, Mike? I did a part-time gig for about a month over at a turbo shop here in town last year and the machinist guy who does the assembly and balancing work told me that they were intended to be noise-reducer compressor housings, i.e. not the typical "jet engine" noises standard housings produce but rather that high-pitched whistle prior to getting into any good amount of boost. One car we had here a couple years ago that we worked on quite a bit had a Schwitzer S300 w/ the same kind of compressor housing. In vacuum, it sounded like the high-pitched whistle, but once he got into it, you couldn't hear it anymore.

B

 

Can you give us any idea on price and who you went through.

 

Damn! I didn't expect so much attention off of this.

I'll pull the NSN and price next time I'm over in the shop. Should be in about 30mins.

I ordered through my CLASS-IX SYSTEM. But ya'll can't use that. And I'm not going to jail for ya'll to get a turbo. I'll see if the box it came in has any contact info.

Hell I'll even take some picks of it installed on the M93A2 (the 5ton).

 

NSN- 2990-01-446-5359-Military use.
Part#- 3802257
MY Price- $546

It is a Holset from Cummins. I couldn't find any direct ordering system online, but I'm sure if you call the nears supplier near you they can help.

 

I am 100% positive. Weather or not the housings get quieter once full boost is reached *may* be just a beneficial side effect. Or, the compressors that once did not have anti-surge, when in surge making its "whoop whoop" noises may have been the annoyance, now replaced with a whistle of the anti surge?

Surge is when the turbo is flowing more air the engine can ingest, so you get a stacking of air within the intake system after the turbo. This stack of air builds up, then is released, then builds up and so on. Hence the honk, honk, honk or whoop whoop noises that can be heard. Now, this stacking up and releasing of air pressure can reach certain frequencies and resonance’s that can destroy thrust bearings and if severe enough break off compressor impeller blades. If you look at anti-surge housings, there’s slots cut in the inlet around the impeller blades (called bleeds). These slots go completely through and are open to the second ring around the inlet. The purpose of this is...... when in surge and the airflow stacks up to the point it backs up past the compressor valute, past the compressors radial blades, that it bleeds out these slots then is recirculated back into the inlet. The slots are placed here for a couple reasons. 1 the forces placed on the radial portion of the compressor blades is minimal and this portion of the blades are short and stronger. The axial portion which you see in the turbos inlet are nearly perpendicular and taller so there’s a longer moment arm, so the forces have more leverage to work the blade back and forth to the point of fracture. 2, at certain compressor RPM's, the radial portion of the blades are doing more of the drawing in of air then the axial "fan like" portion. 3, simply this is were air is entered into the compressor and is not compressed yet. These bleeds also work like a siren. Any time you shroud a spinning blade, and you place an orifice either in front of the blades, or on the side, you'll get a siren sound. Hence the whistle you here with these types of compressor housings. Old school sirens like on cop cars, ambulances etc worked in the exact same principle (a disc was spun up that had holes in it, were a it was placed or sand-whiched between two stationary disc that had holes in it also. When spun up, these holes would open and close much like the ports on our cars and make a "siren" sound). These anti-surge housings work so effectively (against surge), if you look at the two exact same compressors with one having and anti-surge housings, and the other with a standard bell mouthed housing, the compressor map with the anti-surge housing's surge line would be moved farther left. In essence "broadened". But another thing you'll notice, is the standard smooth/radius bell mouthed housing will have a few points more effiency every were else.

Hope this helped more then confused.

~Mike.............

 

Green = bleed slots

Red = backed up air flow being recircutaled

 

quoted "I ordered through my CLASS-IX SYSTEM. But ya'll can't use that. And I'm not going to jail for ya'll to get a turbo. I'll see if the box it came in has any contact info.

Hell I'll even take some picks of it installed on the M93A2 (the 5ton).[/QUOTE]

NSN- 2990-01-446-5359-Military use.
Part#- 3802257
MY Price- $546"

Kenn: GSA Mart (General Schedule Mart) can order any non controlled items in the military supply system, and is currently accesible for military members on a cash and carry basis (I checked with the GSA here in Yokosuka Naval Base)

kenn