Picking up an HX35 this week. It's a 7 blade from an 02 manual cummins. It's has the twin scroll T3 exhaust housing on it with the 5 bolt discharge. Since money is a little tight right now I was simply goin to weld the flapper shut on the wastegate and knife edge the divider on the inlet. Is the oil feed fitting and drain a specific size?

I already have the 5 bolt dp and T3 manifold setup for external wastegate. I know I need a 4 inch coupler for my fp intake. Am I going to hate using the holset turbine housing? Right now I hit 26 psi at around 4k on a .63 T3 hotside

I like the 12cm housing on my V6 setup I run. I wouldnt worry about porting the exhaust housing at all, it will most likely do more harm than good.

I ran the stock downpipe 45degree elbow, and made a plate that bolts to the stock downpipe thing that holds the flap closed (no welding, i can take pics if you want).

The oil line is a oring style line, the return is typical Garrett, I used 3/4inch line and the stock pipe modded and bead rolled.

Even with the stock 12cm exhaust housing, it sounds like you will spool the same speed, and come on with a ton more power than your current setup.

Using the stock housing commonly puts out more power and you will see 20 pounds by 4000 which is streetable and powerful, and yes it will have a little more power than your current setup.

With the BEP T3 .70 a/r turbine housing for the HX35 you would have about the same spool. With the stock housing you have now. I would expect you to hit around 20 psi somewhere in the range of 4200-4500rpms.

Well doing a little mock up, I realized that the HX35 5 bolt housing was different than a regular 5 bolt housing. So I got on ebay and found an HX35 5 bolt housing flange and am just gonna cut off my flange and weld the new one on. I also am going to have pick up a spacer for the head to manifold as the compressor is hitting my water pipe and I'm not going to put a huge dent in it to make it fit.

I can't wait to hear what this thing sounds like spooling up. The ricer in me wants a loud whistle spool like what the cummins trucks sound like. Lol.

Most people just dent the water pipe, and I hear the spool on that turbo with BEP housing is under 4k for 20+ psi.

I agree with you on the not wanting to dent your water pipe, it almost seems like the cheap way to do it, a spacer between the manifold and head would be your best bet but I would watch for a stock radiator fan clearance problem.

rampridersrider said:

Well doing a little mock up, I realized that the HX35 5 bolt housing was different than a regular 5 bolt housing. So I got on ebay and found an HX35 5 bolt housing flange and am just gonna cut off my flange and weld the new one on. I also am going to have pick up a spacer for the head to manifold as the compressor is hitting my water pipe and I'm not going to put a huge dent in it to make it fit.

I can't wait to hear what this thing sounds like spooling up. The ricer in me wants a loud whistle spool like what the cummins trucks sound like. Lol.

Click to expand...

Take out the silencer ring on the compressor inlet covering the MWE ports. That will make that diesel truck whistle

As the others have said, yea, you'll see 20ish psi by 4K with the hx35 and the stock 12cm^2 turbine housing. The 7blade hx35 has a compressor map that goes about 7-8lb/min farther to the right than the 60-trim that you have . And has FAR better high boost efficiency. Now, you'll be hard pressed to get more out of the hx35 with a bolton housing than what a 60-trim in a garrett .63 a/r housing can do. About the same, IMHO. But with MUCH faster spool. Yet, the .70 a/r bep housing probably would give you the flow for pushing the 7 blade hx35 compressor to that 58-60lb/min others have seen. And we know as fact that the stock knife-edged 12cm^2 hx35 turbine housing gives enough flow to push the limits of the 7blade hx35 compressor.

Of course, you need larger injectors and should get better fuel control to exploit such potential.

RyAn007 said:

I agree with you on the not wanting to dent your water pipe, it almost seems like the cheap way to do it, a spacer between the manifold and head would be your best bet but I would watch for a stock radiator fan clearance problem.

Click to expand...

Fluidine radiator, A/C removed with twin 12" pushers on the front of the radiator.

dsm-onster said:

Take out the silencer ring on the compressor inlet covering the MWE ports. That will make that diesel truck whistle

As the others have said, yea, you'll see 20ish psi by 4K with the hx35 and the stock 12cm^2 turbine housing. The 7blade hx35 has a compressor map that goes about 7-8lb/min farther to the right than the 60-trim that you have . And has FAR better high boost efficiency. Now, you'll be hard pressed to get more out of the hx35 with a bolton housing than what a 60-trim in a garrett .63 a/r housing can do. About the same, IMHO. But with MUCH faster spool. Yet, the .70 a/r bep housing probably would give you the flow for pushing the 7 blade hx35 compressor to that 58-60lb/min others have seen. And we know as fact that the stock knife-edged 12cm^2 hx35 turbine housing gives enough flow to push the limits of the 7blade hx35 compressor.

Of course, you need larger injectors and should get better fuel control to exploit such potential.

Click to expand...

So should I knife edge the housing? Some say don't even bother.

I'm running 750's, 255 intank, banjo bolt removed and -6an fed to the rail and to the afpr. Right now at 40 lbs/min I'm seeing 75% IDC on straight pump with a fat tune. I think I should be able to milk some more power out of them for now.


Whats this silencer ring?

you look pretty much good to go. It sucks it is not the same 5bolt housings. it looks the same at first glance. good luck with the setup. post up some logs when your done

rampridersrider said:

Fluidine radiator, A/C removed with twin 12" pushers on the front of the radiator.



So should I knife edge the housing? Some say don't even bother.

I'm running 750's, 255 intank, banjo bolt removed and -6an fed to the rail and to the afpr. Right now at 40 lbs/min I'm seeing 75% IDC on straight pump with a fat tune. I think I should be able to milk some more power out of them for now.


Whats this silencer ring?

Click to expand...

Turbulance is very bad at the turbine inlet. I would round the divider. Rounding is actually better than knifedging (research radiused entry manifold ports).

750s are ok with this turbo. Take a look at water/alky injection.

If you can see into the surge port webbing, then you don't have the silencer ring.

I'm selling my 750's and picking up 1600's. Ive been running 3/2 mix of pump/E85 and am getting 80% idc at 40 lbs/min. When I go to 1600's then I'll run straight E85. I don't have the silencer already then I guess. Cool.

Some updated pics. This is just copied and pasted from another forum.

The car is back up and running now. Just had the new Holset flange welded onto my downpipe last week. This turbo spools so damn fast, even with the 12 cm housing. 20 psi by 3800 rpm in third, with my old stock 6 bolt. Its hard to modulate the boost just cruising. The car just wants to hit full boost, theres no inbetween, its either 0 psi or 20 psi.

It even has a huge difference in sound with the new manifold and turbine housing. It has that "huge turbo" sound. Lots of exhaust tone, but spools fast and hard. I love it. The car is currently not tuned at all. I switched to 1600's and straight E85 and havn't done anything as far as tuning except injector compensation. AFR's are 10.2-10.5 and timing is only 15* up top, but the car still pulls soooooo much harder than it did before on my old Turbonetics "60" trim. I love it so far and once I get the new motor in I'll turn up the boost and hope for mid 50's lb/min and right around 500 whp on the E85.

Pretty stoked right now.


FINALLY got some work done on the GSX. First, some pics:

This is just showing the fitment of the Holset turbine housing with my old RNR manifold vs the new eBay DNP knock off manifold. Notice how with the RNR manifold the turbine housing is nearly hitting the block, this is even with a 1/2 inch spacer between the manifold and head. The compressor housing wasn't even CLOSE with the RNR manifold, but with the ebay manifold it fits perfect.


Please excuse my dirty engine bay. Once the car is driveable its going to Ryan2315's house to pull the engine and clean everything up.













After that I took it to HTP and had Matt weld a new wastegate flange on it. Turned out pretty good.





He also resurfaced the manifold to make sure all sealing surfaces were perfectly flat.




Just showing the collector design of this manifold. I'm actually kind of impressed with it as it actually looks to have a better flow design than an actual DNP.

This is showing where HTP welded the wastegate shut.





This is the oil restrictor for the turbo that me and my buddy Gary made. Its a 12x1.50 -4 an fitting. We lathed the top of the fitting down and put a .078 nitrous jet in the top of it. Had to drill out the inside of it just slightly but it should work awesome.






More pics

look at that monster in the engine bay. Good lord. I love it.

Looks good. Ebay won on this one

. . .Well what really won is exploring your options.

Looks great, nice progress. Big clearance difference between manifolds. thanx for the pics!

that tubular looks nice too, especially because its polished...when he resurfaced did he find that all the surfaces were NOT flat, or did you just do that for insurance?

I only ask because I plan to purchase a SSAC/eBay turbo mani for my new car soon...

I figured since there weren't many people pioneering using the 12 cm housing then I better snap some pics of it. Right now the Ebay manifold is working. I talked to the guy that did all my welding about putting braces on it and he said that he has braced a couple of them and they break sooner. He thinks its cause of the manifold needing to flex slightly, so he suggested welding a brace on my downpipe instead. I'll be doing that shortly too.

I'm hoping to pick up a divided runner manifold from SLS hopefully around the end of the summer after all of my vacations my gf and I are taking. Lol.

KPEclipse said:

that tubular looks nice too, especially because its polished...when he resurfaced did he find that all the surfaces were NOT flat, or did you just do that for insurance?

I only ask because I plan to purchase a SSAC/eBay turbo mani for my new car soon...

Click to expand...

He honestly didn't even tell me he was doing it. He just did it. He only did it for insurance as far as I can tell. I nor he ever checked it for flatness.

So where's the video on this thing..? Come on man!

I got rained out today so I might take a few videos here in a minute. Will give me an excuse to get off my couch. Lol.

Went to take some vids, but my camera isn't working right. So I'll do it another time.

I did finally pull a log on the car, and in second gear the car is flowing 40 lbs/min at 20 psi on a stock motor with stock IM and cams. IDC is at 50% on straight E85 and 1600's. Timing is at 16* up top. I havn't really done any tuning at all and I'm obviously seeing zero knock.

If I could guess I would say power output is probably around the 350-380 range. Last year with the 2g head and intake manifold on my T04E "60" trim, boost set at 24 psi, E85/pump mix, timing at 17*, 38 lbs/min, the GSX put a car length on my buddies bolt on LS1 Camaro from a 40 roll. His car goes 12.4 at 110, and makes 340 hp, 350 torque.

With some fuel adjustments and timing adjustments I could easily be around the 380-400 range. The car MOVES right now. Very quick. I could up the boost, but my buddy is buying my motor tomorrow so I really don't want to hurt the engine. Lol. There is no doubt in my mind that with the new motor setup and some cams the car will easily do 480-500 and thats probably only possible cause of the E85. I'm hoping for 125 mph traps full weight and 130 gutted.

So you didnt need the spacer with the ebay manifold right? Also did it stay that same color or it did it burn off as soon as you started it? i just ordered the exact same one for my HX35. Why did you have to reweld the external wastegate flange on the mani? Where did you get your oil feedline from?

With the lack of mitsu bep housings out there, I think that I may be going this route too. I wonder if there would be any success if someone were to weld a divider into a dnp or even the eBay t3 manifold. I'll probably pickup the eBay housing and blockoff the wastegate tube and stay with the stock internal wastegate for now. I've had my hx-35 sitting in the garage for months now and am itching to get it installed.