Hey guys I have been searching the site reading some of the old posts on turbos and various upgrades. With my setup (see sig) what upgrade/ mod would you guys recommend? I do not plan on upgrading injectors or anything in the future. I would like a little more whistle out of my turbo but it runs great now. What would be the advantage of the HTT upgrade kits? Thanks!

 

The main advantage is more air, which equals lower EGTs. But, unless you get the Stage4 with the MWE (mapwidth enhancement) slots, there is the possibility of surging.

I would stick with the 18cm housing, considering you have no OD, and will likely be near the upper end of your RPM range most of the time.

Daniel

 

Will the HTT Stage IV give me a cooler boost with the potential for more air? You guys think it will make the turbo whistle more than the stock H1-C? Thanks for all the input!

 

All HTT upgrades have MWE's, so they all scream under boost If you're leaving your injectors alone, I'd go with a stage III. It's about a hundred bucks cheaper and will clean up my stockers with a maxed pump. The stock comp housing on non-ic trucks is very quiet, so you would notice a huge difference regardless of what 'stage' you go with.

 

I'm with Greg on this. The Stage IV will flow a little more air, but it's also quite a bit pricier. The Stage III with the 18.5cm housing will be a good turbo EGT wise, and it will whistle nicely.

 

Agreed. Need I say more?

 

Fill me in on the acronyms here. What is a MWE?

 

HTT has a bolt-on Stage III kit for the non-IC trucks.

MWE is Map Width Enhancement. It's a slot in the compressor housing that allows excess airflow to recirculate back to the intake. As well as making a nice whistle, this prevents turbo surging at low RPM and high boost.

 

So, for my non-IC Cummins, would you guys recommend I get the MWE or a bolt-on? Are there any practical differences in them like horsepower gains or boost gains? Thanks!

 

Any HTT upgrade you buy will have MWE.

 

The Stage III advertised on the HTT website says that it will only directly bolt up to a 91+ model that came from the factor with the intercooler. Is that the Stage III you guys are talking about? I think I might want a 3200 governor spring in the future so would the Stage III be sufficient? Thanks!

 

Call and tell them you have a non-intercooled truck. They will know what to send you.

The Stage III setup will be great until you decide you want POD's.

 

There is no 'bolt-on' option for the non-ic crowd. What HTT will send you, however, if you specify a non-ic truck, is a housing without the flange for the clamp-on 90* elbow that ic trucks have. It'll look just like what you have on the truck now, only bigger. That's where the problems start. The non-ic crossover tube is 2'', as is your present compressor outlet. The HTT unit will be 2.5'', so a silicone adapter in the 2.5'' to 2'' flavor will be needed. www.stylinmotors.com is where I got mine--they're a site sponsor I also trimmed my crossover tube for a better fit. Not entirely necessary, but I felt better about it when I was done.

 

I stand corrected.

 

So what is producing the long sought after whistle?
How is the MWE creating the extra noise compared to a housing without MWE?

Would there be any dangers to using SCH 40 PVC or ABS to fabricate the pre and post turbo plumbing temporarily or even permanently besides maybe the under hood temps?

About how many RPM’s are the turbo’s spinning 12CM vs. 18Cm at full boost?

Thanks Jim