I think I know what turbo my truck has. Apparently it isn't a normal HX40 because it has an 18cm2 exhaust housing. It has a 6-blade compresser wheel and a 4" exhaust outlet. Wastegated.

With stock injectors and pump turned up a little, it is really laggy. Having a 5 speed, I wanted to change to a 12cm2 to help holeshot (I drive mostly in town and highway 75 mph and little towing) but the smallest housing available for the HX40 is 16cm2. Would changing to a 16cm2 housing improve holeshot much? I was quoted $500 for the housing alone. I really want to keep the 4" outlet, but $500 seems like a lot for a housing on a turbo I don't like yet.

I was also quoted $1500ish for an HTB2 62/12. Yikes.

I don't know a whole bunch about these turbos, so make sure you are specific when talking about different options.

Should I just get the housing and plan for injectors or get an HX35/12 and change the downpipe?

Waaaay too many options. I just can't stand the lagginess right now.

EDIT: Max boost I have seen is 20psi.

 

The 40 is gonna be laggy wven with the 16. Cheapest route, buy a good H1C and then sell the 40 to buy blown HX just for the 12cm. Then with a little more $$$ buy a stage3 or 4 compressor upgrade. A good 40 will go pretty good if it has the T-3 flange.

 

Get an hx35 and swap over the compressor wheel and housing and you will have a 35/40 hybrid with whatever size housing you find.

 

What parts would I be left with if I did this? I guess I don't fully understand exactly what the HX35 part is. Is it just the compressor wheel housing? It seems like there are four parts to a turbo. Compressor housing, compressor wheel, exhaust housing, exhaust wheel. Correct?

 

He's suggesting you get an HX-35, swap the compressor from the HX-40 onto it, and then bolt the homebrew 35/40 hybrid (with suitable downpipe) on the truck. Should run pretty good with that setup.

There have been several good suggestions. I don't think I would throw another $500 at that HX-40.

 

Ok. That makes sense. I'll be on the lookout for an HX35/12cm2 w.g then.

 

I am running an hx35/40 hybrid/12cm and love it! Find a hx35/12cm for cheap and get a rebuild kit for hx35/40 from HTT. Pull the shaft out of the 35 and slide it into the 40 put the 40 comp. wheel back on and torque it 150 in/lbs. Put the comp. housing on.Then bolt the 12cm housing on the turbine end. Thats what I did and have had no problems.

 

I think rbrettctd gave me the info for doing mine. IIRC. Thanks!

 

Is it safe to say EGT's will drop with an HX35/40 hybrid assming pump settings are the same? I'm seeing 700*-800* flat ground at 75mph up to 1200* up slight hills if I'm easy on the throttle. I haven't touched the pump. All settings are from the previous owner.

As I said before, the max boost I've seen is 20lb. WOT. That seems low to me. I think it's just too much turbo for what I have now.

 

i had a hx40 and a 16cm with stock injectors and a maxed out pump, i didnt think it was very laggy i acualy thought it was better then my h1c with a 16cm, and i hit 34 pounds, i can get a core hx40 16cm for cheaplike 200 bucks, with broken shaft or somthing
joel

 

Yes, cruise EGT will be down around 650 or so, a slight hill will put you around 800.

 

Criminey. Thanks for the quick reply guys! This has been a huge help. My search begins...

 

Skinny, did you reuse the hx40's turbine wheel? If so any machine work needed to fit it into the smaller 12cm hx35 housing?

 

I did not use the 40 shaft/turbine wheel w/ the hx40/12cm setup. You use the 35 shaft/turbine wheel. They are the same shaft just different turbine size. Use the 35 shaft in the 40 housing and then put the 12cm turbine housing on the hot side of the hybrid 40 setup. It will go: 40 comp. housing, 40 pin wheel, 35 shaft, 40 bearing housing, 35 turbine wheel, 12cm housing. Make sense? It confused me at first too, but once you start on it and see the parts in will really make sense cause it can only go one way.

 

No wonder it's called a hybrid...

What size exhaust outlet do you end up with? Too many numbers to keep it all straight.