jrussell

So the HTT stage III or IV H1C upgrade would actually flow better than a stock HX-35. The only big difference I see then is you get the MWE slot with the HX-35 and I assume you don't with the H1C upgrades?

G1625S

All HTT housings for the H1C have MWE slots....and they don't come with a silencer ring so they scream right out of the box

jrussell

Wow, this sounds like the wtg for a turbo upgrade!

Generally how much fuel would you have to throw at a Stage III or IV H1C before you needed more turbo? This upgrade probably wouldn't be enough with bigger injectors like POD's right?

G1625S

Well, you can throw as much fuel at it as you want, but how much it'll burn is another story. Lot's of floks run POD's with stock turbos, at least for a little while. Wannadiesel is running POD's with the stage IV and sure, he can blow a ton of smoke if he wants, but he can also drive around the POD's and have it run pretty clean if he wants. Plus, I hear that truck really hauls the mail! The bottom line is that HTT upgrades for our turbos are really the best bang for the buck. Kinda like POD's are the best bang for the money when it comes to injectors. Will the stage IV completely clean up PODs? Probably not. Do you want to spend $1600 to buy a turbo that will? That's up to you, but for less than a grand, POD's and an HTT compressor housing make an old truck new again on a realistic budget.

edit: I'm running stock non-IC injectors and I get a fair haze at WOT with 40psi, so my humble opinion is the stage III will clean up stock non-IC injectors or Bosch 190's pretty well.

Begle1

If you want you can always find a HT3B bottom turbo for well around $400. With a wastegate on the top turbo, that'd make a decent twins set-up... And that'd be a lot of air.

jrussell

Thanks for all that info, guys!

It sure is nice having HTT just down the road from me. I went down there and talked with Paul a few minutes ago. He really knows his stuff and set me up with a Stage III upgrade. He said the main difference between a Stage III and IV is the IV flows about 10% more. He said most people don't notice a difference unless they have big injectors and a lot of fuel. Both kits are 100% bolt-on and any machined parts needed for the Stage IV are included in the kit.

I really wanted an excuse to go with the IV for only $85 more, but being that I plan on sticking with stock injectors for a while I opted for the III. Should be installed by tonight and I'll let you all know how it does!

wannadiesel

I have too much fuel for the Stage IV. POD's and a ground AFC lever are more than a hybrid can handle.

I would recommend that folks stick with the Stage III for a low budget upgrade, I think it's a better value. If you need more air than that, just bite the bullet and get a bigger turbo or do twins. I wish I had.

Micaiahfied

wanna, in that scenario could you use the stage III on top or would it be too small for a top turbo?

wannadiesel

A hybrid makes an excellent top turbo.

Begle1

So at what point does a Stage IV or HX-35 turbo on top become too restrictive?

chuxtruk

There you go again being a bad influence on us stockers, Dave!! I sent them (HT Turbo) an email tonight so maybe by this time in a week or so that stage III kit will be ON THE WAY. I'm in search for more power and this upgrade will start the show!! Thanks!
Chuck

jrussell

Didn't want to start a new post for the report, so here it is...

Installed the HTT Stage III with the turbo still on the truck and it couldn't have been any easier. Had a harder time getting the downpipe lined back up and the clamp started than anything.

Before HTT Stage III: Max boost was 25psi and EGT's quickly approached 1300* (pre-turbo) after a few seconds with it to the floor (in OD). The EGT's seemed to still be climbing a little at that point, but I wasn't going to find out just how much past 1300* it would go. I would also get a very slight smoke/haze at WOT and a big puff of black before the turbo spooled.

After HTT Stage III: Max boost is now 30psi and EGT's peaked at 1200*. Pedal was to the floor for a good 10 seconds after and they didn't seem to keep climbing. Still get a decent puff of black smoke before the turbo spools (of course), but WOT smoke/haze seems to be gone.

I can't figure out if the new compressor/housing spools faster or slower. It seems to have a hair more lag before spooling, but it seems to build boost/spool faster than the stock one. I figured a bigger compressor wheel (more mass) would increase lag, but it seems to build boost much faster once it starts.

Overall, I would definitely recommend HTT's Stage III upgrade for someone who doesn't want to go all out with big injectors and a ton of fuel. I don't see how you can get a bigger bang for your buck (especially on the air/turbo side of things). I'm still running the stock 18cm housing and 3" exhaust (for now!), so I expect to see much improved spool times and EGT's with my upcoming housing/exhaust mods.

G1625S

Glad you like the stage III! Your spool will be slower due to the additional mass of that new pinwheel....but once it lights...look out!

jrussell

Boy you said it!

The sound is very different too. I think my stock H1C was actually a little louder (inside the cab anyway) and had a lower tone. This one has a very high pitch tone and whistles with very little or no boost...it even whistles going down a hill with the tranny in a lower gear!

What do you think an efficient max boost would be for this hybrid? Also, do I understand this correct...Do the MWE slots prevent the turbo from overspooling when used in a smaller housing? Does this then eliminate the need for a wastegate to protect the turbo?

gman07

Unfortunately, no. The MWE slots help stop compressor surge, which is when the turbo is trying to provide too much boost while flowing too little air (trying to get high boost at low RPM's). It's bad for the turbo, and the MWE slots improve it by moving the "surge line" on the compressor map to the left (thats a good thing). So you will still need a wastegate to prevent overspeeding.