And I'm seeing some smoke at full throttle and still only getting 10psi of boost. I think I need to test my boost gage to make sure it's workin okay. I figured with the tiny 9cm housing I'd be making killer boost but It doesn't seem so. There were little tiny nicks in the turbine blades but nothing I saw to be too alarming. I'm thinking of going to an HX35 with a 12cm housing but I really don't want to have to fab another exhaust since it's so tight in my engine bay. The HX35s have more efficient compressors don't they? I really need to see more boost I think because of the smoking deal. Maybe my air filter sucks. Who knows.

I still need to install my piston lift pump and 3200 gov spring. I can't find the cummins parts anywhere that I need to put the pump on.

Anyone have any bright ideas on where to go from here? I'm looking for more power with the least smoke possible.

 

The HY-35 with the 9cm housing will give you a lot better boost numbers than the HX-35 with a 12cm. I'd check your guage like you said and also make sure there aren't any boost leaks. I'm surprised you're not getting more boost

 

Make sure the wastegate is closing completely. and of course it is free to open completely.

 

Other than possibly low bost and the smoke issue, how's the performance? Which injectors are you running? I've got a 4BT that's going to get some massaging, but probably more gently as it's for lots of towing.

 

I welded the wastegate shut. I checked for boost leaks tonight and I think there aren't any. I hooked up compressed air to my gage at 30psi and the gage read 25psi. I ordered a new boost gage. Mine doesn't read completely zero at atmospheric anyways. It's weird I can hit 10psi in second (ZF trans) and only like 7 psi in 3rd. Even less in 4th. I tried with no air filter on and the effects were the same.

I'm running whatever injectors it had stock. This engines background is kindof a mystery. I'm not sure if it came intercooled or not. I do have a nice bar and plate intercooler rated at 600hp or so.

I'm still hankerin for more power and lower EGTs. I'm really thinking about the HX35 since I may need more air once I go for more fuel down the road. A 12 cm housing would allow me to be a little cooler on the EGTs as well.

 

something's definitely wrong...

I can hit ~37PSI in 3rd (5-speed manual) with my H1C w/ 12cm wg housing...and this was just with the 3200 gov spring, before any pump mods...

Greg

 

I think the turbine wheel may be messed up. I did find 2 chunks of metal in the housing but the wheel looked pretty good. Nothing rubs on the housing anywhere.


I used to run an H1C with a 16cm housing and the boost was about the same but a little less resonsive.

 

Shut truck of and spin the compressor side of the the turbo.......dust it continue to spin after you let go?

Just wondering if the bearings are tying to seize and not allowing it to boost like it should!


You said that you removed the air filter system!?

is this eng. intercooled?

boost should increase with every gear that you add,,,,,especially with the waste gate welded shut!
Did it actually get welded(waste gate) slightly open

could your intercooler or intake system have a restriction in it some were. this could make some, as to why your boost gets lower and lower with every gear up that you go

You could test this by putting a boost gauge just after the compressor and a 2nt one in the intake and see if the two boost are fairly close to each other!
if it has a intercooler and it is fairly efficient then you could have a few pounds less at the intake due to air cooling and condensing. this would be good!
What your looking for is say 20 or 30 pound boost off from the compressor side of the turbo and only 10 at the intake!
This would indicate bad restriction in the intake system some wheres!

 

Have you tried spinning the compressor wheel while the engine is off? Make sure it spins freely and doesnt stop within a second or two. Maybe a rebuild is in order? What are your EGT's like at WOT?

 

I ran an HY 9cm om my truck in sig for a year, and could get it up to 32 psi at WOT and never went over 1000 egt's. Awsome for in town driving. I now have that turbo switched over to my recently aquired W250 1993. This will be good enough for mountain use. Something is either wrong w/ your plumbing(leaks) or your boost gauge and/or boost tubing.

 

The shaft spins nicely. I don't think the intake could possibly have any restriction since it's all 3" mandrel bent tubes with long strait sections.

I ordered a new boost gage.

I have a feeling my turbine wheel is ******.

I got the turbo for $175 used so maybe you get what you pay for.

 

How did you leak check the plumbing?

 

Well I didn't check the plumbing very thoroughly because it's all silicone connected with tbolt clamps. There aren't even that many connections.

What I did do is thread a 1/4npt fitting into where I had my boost gage outlet and put 20psi from shop air into it. I felt around for air leaks around the connections but most of the air was just coming back out the compressor on the turbo. Oh well...

I now have bigger fish to fry because my pipe on my manifold that I welded on to relocate the turbo cracked real bad and now I get no boost at all due to the ridiculous exhaust leak. I'm gonna take it off today and reweld and reinforce the thing. My new boost gage should be in soon do I can recheck everything once it is.

 

Made some progress tonight...

Got the huge exhaust problem fixed. Got it nice and reinforced now.

Found a boost leak and tightened up the rest of the clamps. Boost hit 16psi in 3rd. Pretty cool. If my gage is off by -5 psi that would put me in the 20s but who knows. It definitely kicks more *** now. Sweet deal.

 

Glad to se you getting the bugs worked out of it!