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Discussion Starter · #1 ·
I have racked my brain for the last two weeks searching to decide which turbo to use on my build. there is a lot of info out there and a lot of debate. I am hoping for some guidance on what will be best for my build and situation.

I have a wh1c off of a 94 dodge, and a Hy35 off of an early 2004 dodge. I am looking for info on which would be a better turbo to use on my build. My budget is to the point that I will have to put one of these on and get the truck on the road, and later decide if i want to buy a new turbo that may be a better fit.

I have an unknown cpl 4bt, ve pump with aneroid supposedly from a step van. I have rebuilt the engine with head studs and o-rings to allow for future growth.

Engine Mods:
THD fuel Pin
3200 spring
Colt Cam stage 3 camshaft
DDP Stage 3 injectors
Steed Speed exhaust manifold
Frostbite intercooler 30"x 13"x 3", 2.5" in/out (35 psi max constant)

Pump fueling, and timing will be adjusted as necessary.

This will go in an 85 K5 Blazer
47rh transmission, dodge 208 t-case
35" tires, 3.42 gears 80mph @ 1,800 rpm. 60mph @1,360rpm

The truck will be an on road weekend vehicle for my wife, and a backup driver for me. No towing.
My wife will just drive it around town, and I will run 80 on the interstate to work and back.

My thoughts so far:
HX35 may surge in lower boost situations, 12 cm housing take longer to boost, but "better top end"

Hy35 will spool quicker than HX35, but "limited top end"
I am not sure how limited the top end would be, I would plan on keeping the wastegate and modify if necessary.

There is alot of talk about the HX30, and I bet it would spool quick, but I would also wonder if it would be a big choking point in the higher rpms. I will have a very hard time buying a new turbo without having the truck on the road first to understand how it will drive with one of the turbos that I have.

I am not afraid of moderate smoke or 1250 plus egts on the short term as you are accelerating, but would not want flat highway speed at 1200 deg. With the auto trans I am less worried about instant spooling, but don't want as much lag as my first gen Cummins 5 speed with the 21 cm h1c.

I am leaning towards the HY35 with the 9cm housing for quicker spool, from research here it seemed like the hot item, and then fell out for the HX30.

Between these two choices, which would be a better fit? How do you think drivability will be?

Also if I am way out of line with this combo please help me understand how.

Thanks
 

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Neither one. They are both too big to use as a stand alone turbo on a 4bt. All of those are HX35 compressors and it's just not what you want on a 4bt. They were all fine on a 5.9. The specs on the WH1C are identical to an HX35W. It was only used 1 year on the Dodge. The HY35W is still an HX35 compressor with a 9cm2 turbine housing. It's been tried on a 4bt but you usually end up with slow boost and high EGT. Most of your power will be in the higher RPM range where you aren't planning to run. 1800 RPM @ 80 MPH is OK but that 60 MPH number looks a bit low. Getting close to lugging the engine. Need to drop out of OD there. 1700-1800 RPM is sort of the magic spot where you have the most torque. Now for the HX30W turbos they have proven to be about as good as they come on a 4bt. Only other turbo that gets good reports is the HE221W which is smaller yet. The largest single that is usually recommended is the Super HX30W. That has a 46mm inducer on the turbine and a 6cm2 turbine housing. Just slightly slower boost than the standard HX30W 44mm. Frankly, for your planned type of driving, either of those turbos would do fine. Both can go north of 200 HP. Will start to lose ground approaching 250 HP. At that point you go twins. There, a 44mm HX30W fed by you WH1C can get you to 300 HP which is about all the VE pump can do. North of that will take a P pump. You also don't want to be running 1250 deg EGT. 1000-1100 is common on a well tuned engine. You don't want to see smoke when you're running. That's wasted fuel that only creates heat and no power. The leaner you run a diesel the colder it runs. Exact reverse of a gas engine.
 

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I'm with Charles I started with the hx35 and then changed the exhaust housing from the normal 12cm to a 8cm and it was better with the 8cm and about the point where a 4bt's torque starts to drop like a rock it comes on well but is not truly drivable IMO compared to any of the quick spooling turbos. To get maximum fun ,drivability and work from your 4BT you want to be making good boost by 1,500 so you can start fueling hard to fully use the sweet spot from 1,500 to 2,000...
With my compound build I still live in the same RPM range the factory had in mind and while I'm still making good boost with EGT's under control the drop in torque past 2,300 is drastic get the right turbo with a good IC and gear it right and it will treat you like B series Cummins should.
 
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Discussion Starter · #4 ·
Thanks for the replies.

eggman, Im trying to understand how bad the big turbo would be. Was it so bad that you would not even drive the truck, or you just noticed a big improvement once you change to the HX30? I am comparing to the 6.2 diesel that was last in this truck, and I would think it would be a great improvement even with a little turbo lag, but I have no experience to base this off of rather than my 6bt.

Your sig shows a ZF5 crew cab. I assume that is what you had the Hx35 in? What gear ratio and tire size does it have? Would the turbo lag be more manageable with an auto if you were not shifting and trying to re-boost to accelerate?

Did you ever run the HX30-6-w as a single? how bad were highway hill EGT's?

My background is with a 6bt in a square body chevy crew with at 62 phatshaft with 12 cm housing. I do love the quick spools when shifting. And when I compare to my previous set up with the H1c 21cm housing the previous was really laggy, but for this build I would be ok with lag to get it on the road. But if egt will be so bad that it would not physicaly drive down the interstate I will have to postpone the project until can do a new turbo.

Thank you for the discussion, as I am trying to fully understand how these turbos will work for my situation.
 

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I would guess that the hx35 8cm was around 130 hp but was a dog below1,800 IIRC but was not bad from that point, the single I ran and really liked was the he221 it would for me make 28psi at 2,000 and it would make 15psi by 1,500 it worked well for me from sea level to 8,000' when tuned for 5,000' and did well in my rig which weighs 8,000# as it sits. I have 3.55 gears and 33" tires so I turn 2,000 at 70mph, with the he221 it was quite happy at 10K CGVW and OK up to 12K it did a trip at 16K and the drive train was still adequate but the rest of the truck was less so. I tried 3 different setups... {A huge waste of time and coin} before the 221 but it was the point in time when the best turbo was just being explored. When I started the swap I really needed a 6BT but the Highboy Fords do not want a long and heavy mill over the front axle so I went the 4bt route the 221 was a good turbo but when it was time to do a rebuild I opted for compounds as I had t pair of core turbos that were ideal and with them one step up injectors a large IC and a little tweaking to my VE pump the 4BT is comparable to a stock 24 valve, the only "trick" parts I used in the build was ARP head studs I have max boost set at 40psi and fueling where with an extended wot run up a interstate grade I will see 1,200*.
Last thought if you have driven a 6bt truck you would be extremely disappointed with a 4bt with either of those turbos.
 

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Spoken by the man who has tried options. In the early days the HY35W was thought to be a good answer but guys soon found the HX30W would run circles around it under 2000 RPM. With a 4bt you think smaller instead of larger. As Steve said, the HE221W is a good turbo but requires a bit more work to install. It has a different exhaust flange so an adapter is needed to attach to the exhaust manifold. Oil line and exhaust outlet are also different. The other thing that sometimes comes into play is the boost regulator is attached to the compressor housing which can make it more complicated to install. That why most end up with the HX30W. Same oil line and exhaust ports as the old H1C and you can clock the housings easily depending on what exhaust manifold you have. I'd guess the 44mm HX30W would only be slightly slower in boost than the HE221W. And that would depend on which HE221W. Those came with various sizes of turbine housings from 5.5cm2 to 7cm2. Since most of you driving will be 1800 RPM or less, the turbos that boost the fastest are what you need. The 46mm Super HX30W will be slower than the 44mm. The HE221W has a 43.5mm inducer so it's similar to the HX30W.
 

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Discussion Starter · #8 ·
Thanks for the opinions.
For the sake of thorough review, can anyone direct me to where I can find and buy a hx30? I would prefer the Super HX30W , or HX30W 44mm. with 6cm gated housing. My searches that last couple days have not produced any in stock options.

If I cannot find one that I can afford I will be back to my original question of HY35 or wh1c to get this truck up and running.
 

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Look up Benzforce. He has them. That is where I got mine. Very nice to deal with and ships fast. He is in Texas I believe
I second Benzforce. Super nice guy and shipped it quickly.
 

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There are lots of sources for that Super 30. Do a search for "Cummins 4051167" and you'll find many listings. On ebay, about the cheapest I've seen was $598 delivered. That's for the turbo only. You must add in the oil line and whatever air outlet you'll be using. There are some cheaper ones out there but they don't have a Holset ID label which would be a bit of concern. Also those don't say genuine Holset in the description. There are also some kits that have oil lines, compressor outlet elbow, and even exhaust elbow.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500 superHX30w
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I also got the super 30 from benzforce. Nice guy, good communication. He didn’t seem to have a lot of knowledge of the cummins end of things, but has available a lot of what you would need parts wise. You probably know some of the fittings for intake/exhaust are the same for hx30/hx35 and fit super 30, they might not be advertised under super hx30 but instead under 30/35. Also find a good hydraulic shop and bring your fittings in. Parker seemed mostly doing well making up lines. Usually takes two steps, mock up then taking it home/clocking the fittings then final crimps. I found going into it the more I knew what to ask for the better, as the guys behind the desk mostly wanted to get you fitted up and out the door and didn’t have the time or desire to answer newbie questions like on what size line and restriction is ok for a turbo oil supply line.
 
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