The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread (3 Viewers)

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Jdm Subaru legacy. It looks like the td04hla is the same size turbine as a common td04hl, but my he221w has a smaller turbine wheel. It looks like the versions which come with the 6 or 7cm turbine housings have the td04hl sized wheel, but my 5.5cm version has a smaller turbine wheel.

I guess I'll try and fit the td04hla then and see how it runs. Then consider whether to get the bigger sized he221w to create a hybrid. The holset turbine wheel is meant to be more efficient, but you've posted before that some of the td04 compressor wheels are better?
 
These are the wheel sizes on the td04hla… Is this one of the ‘good’ compressor wheels?
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Mine HE221W is smaller than the common ones, I measured the compressor wheel 40.9/58.1 mm, turbine wheel 44.2/48.8 mm.
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I haven't measured my compressor wheel, but that turbine wheel matches mine. It's not just the wheel sizes though, the centre section is different where it fits into the turbine housing, you wouldn't be able to swap turbine housings between the regular he221w and our 'small' version. It's basically a totally different turbo.

I've had another change of mind since my last post, and have ordered a 'large' he221w from Trundles here in NZ. I spoke to Chris on the phone and he confirmed the dimensions of the he221w centre section where it fits into the turbine housing, and they appear to be the same as the td04hla, totally different to the 'small' he221w which he also sells (and he is aware that they're totally different turbos).

The small he221w has been a great performer for me, but ever since having my truck on the dyno I've been sure the turbine housing was too small at higher rpm. Now I know it's probably the whole turbo that's a bit on the small size. Chris Trundle said he would expect a 3.4l motor to be choked pretty badly by it. Hopefully I don't lose too much early spool up going to the larger turbo.
 
I haven't measured my compressor wheel, but that turbine wheel matches mine. It's not just the wheel sizes though, the centre section is different where it fits into the turbine housing, you wouldn't be able to swap turbine housings between the regular he221w and our 'small' version. It's basically a totally different turbo.

I've had another change of mind since my last post, and have ordered a 'large' he221w from Trundles here in NZ. I spoke to Chris on the phone and he confirmed the dimensions of the he221w centre section where it fits into the turbine housing, and they appear to be the same as the td04hla, totally different to the 'small' he221w which he also sells (and he is aware that they're totally different turbos).

The small he221w has been a great performer for me, but ever since having my truck on the dyno I've been sure the turbine housing was too small at higher rpm. Now I know it's probably the whole turbo that's a bit on the small size. Chris Trundle said he would expect a 3.4l motor to be choked pretty badly by it. Hopefully I don't lose too much early spool up going to the larger turbo.

What size HE221W are you going up to? The 7cm housing?
 
'Small' wuxi he221w vs 'big' td04hl type he221

So as posted above the small he221 has a different turbine housing fitment, and the compressor housing fitment is also different. The big he221 seems identical to the td04hla for both. However both versions of the he221 fit up basically the same. I was able to use my existing dump pipe though I had to trim down my 'divider' that creates the divorced wastegate, an ordinary dump pipe would be a straight swap. The compressor inlet and outlet fitted up pretty well, though I had to force the silicone connectors a little, but I probably had the compressor housing clocked slightly differently. The oil drain and feed are the same. The wastegate actuator mounts differently and the rod is a different length, but ends up more or less in the same place for both turbos.

Performance... The big he221 does seem to spool slightly slower, but after about 1700rpm starts catching up and seems to end up at 20psi around 2000rpm, the same as the small version. I didn't go for a proper test run as we are in level 4 lockdown here, so just on the flat roads near to my house. Without testing on a hill it's hard to tell, but it looks like the big he221 starts boosting at about 1300rpm, vs maybe 1100rpm with the wuxi. At 1500rpm the big he221 is probably at about 6psi at most, where the wuxi is probably close to 10psi.

The big he221 did seem to pull a bit harder above 2k rpm, and rev into the 3000s nicer, though it was also wstgated to slightly more boost (maybe 23 or 24psi vs 20psi that I normally run). Egts didn't seem to climb as quickly. It would be interesting to try the 6cm housing for the big he221, I suspect it would clearly outperform the small wuxi he221. For an everyday driver the 7cm big he221 would probably be the winner in this comparison. However I suspect I might miss the very early spool of the small wuxi turbo, particularly offroad where I love being able to idle into mud holes or sand dune climbs in low 3rd then unleash carnage and get the tyres spinning really fast once the traction goes.

This leaves me pretty optimistic that the twinscroll 8.5cm housing is going to be an absolute ripper on this turbo. In my research I came across a figure of 1.6 as the factor to multiply a single scroll housing size by to get the equivalent spooling twin scroll. 8.5÷1.6=5.3cm...
 
I tried making a video whilst test driving, but with the phone on a holder attached to the rear window you couldn't really see much. Here's a freehand video of the boost and egt gauge, recorded on a private road of course. Gives you an idea of the performance without totally sending it.



 
These are the wheel sizes on the td04hla… Is this one of the ‘good’ compressor wheels?View attachment 2762151View attachment 2762152View attachment 2762153View attachment 2762154View attachment 2762155

Those are the good turbines. The thing to spot is the turbine blades looking backswept at exit. More restrictive turbines have the blades finishing radially.

For the compressor wheels. High pressure wheels (e.g. HE221) have the blade outlet closer to radial. High efficiency wheels (e.g. MHI) have the blade outlet backswept.
More radial blades throw air outwards more, they generate higher pressures but have more turbulent mixing unless you fit a huge compressor housing to them.
More backswept blades provide a gentler exit for the air with less turbulence and hence better efficiency.
 
I tried making a video whilst test driving, but with the phone on a holder attached to the rear window you couldn't really see much. Here's a freehand video of the boost and egt gauge, recorded on a private road of course. Gives you an idea of the performance without totally sending it.





Yeah that is pulling out faster than my BJ74.

This is the HE221W I found online. Says it's legit Holset.
Holset HE221W 4047745 4047746 HE221 (7cm) - https://www.benzforce.com/collections/holset-he221-and-parts/products/holset-he221w-4047745-4047746-he221-7cm
But there aren't any specs on it other than 7cm.
 
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Well the Id tag says he221w, it resembles all other 5.5cm he221 photos online. The only spec I found for a he211 showed slightly smaller wheel sizes again. It would be interesting to compare them though, you'd suspect they might share the same centre housing.
 
Well the Id tag says he221w, it resembles all other 5.5cm he221 photos online. The only spec I found for a he211 showed slightly smaller wheel sizes again. It would be interesting to compare them though, you'd suspect they might share the same centre housing.

I've never dug into it too much. Holset had the HE211 which later became the HE200. The guy I came across who knew the most about them was a Norwegian going by the name Alcaid. I helped him size a compound set for a VW 1.6td using one of them. I'd expect them to all be TD04 related. That frame is too useful to ignore.
 
Anyone have issues with cooling line rubbing on wastegate for the ct26 install on 1hdft.
 
8.5cm twinscroll he221w initial testing:

Spoolup is almost as quick as the smaller Wuxi he221 with the 5.5cm housing. Looks like the boost gauge starts to move at about 1200/1250rpm. Seems to hit 10psi around 1500, and 20psi at 2000rpm. The Wuxi 5.5 started seeing boost maybe 100rpm sooner, and the 7cm about 150rpm later.

Cruise egt is about 20c lower than with the 5.5cm (340c at 100kph vs 360). Cruise boost is maybe a few psi less (just under 10psi, the 5.5cm about 12psi).

The big change is full load egt. Down by at least 100c, maybe as much as 150c. Climbs quickly to 450c, then slower after that, looks like it wouldn’t pass 550c at all, but can’t say for sure yet without any real hills to play on close by. The 5.5cm was quick to hit 600c, then continued to slowly rise to 700. (Full load fuel was bench tested at 124cc).

I wouldn’t say the motor pulls any harder at lower rpms, but it does seem to go harder above 2000rpm. I’d possibly go as far as to say that it’s as quick on the 34” tyres as the 5.5cm setup was on 31” tyres.


So based on the above, the twinscroll works like it’s meant to. In this case a bigger turbine housing is able to spool up like a smaller housing, but flow better at higher rpm. I don’t think much exhaust is getting wastegated. I plugged the wastegate actuator line and only got maybe 25psi (about 5psi more). I guess the egt is too cool to produce more boost? The exhaust doesn’t seem as loud on full load as the 5.5cm, when you could really hear the difference when the wastegate opened. The big gain then with this setup seems to be gaining headroom to add more fuel whilst keeping egt safe.

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8.5cm twinscroll he221w initial testing:

Spoolup is almost as quick as the smaller Wuxi he221 with the 5.5cm housing. Looks like the boost gauge starts to move at about 1200/1250rpm. Seems to hit 10psi around 1500, and 20psi at 2000rpm. The Wuxi 5.5 started seeing boost maybe 100rpm sooner, and the 7cm about 150rpm later.

Cruise egt is about 20c lower than with the 5.5cm (340c at 100kph vs 360). Cruise boost is maybe a few psi less (just under 10psi, the 5.5cm about 12psi).

The big change is full load egt. Down by at least 100c, maybe as much as 150c. Climbs quickly to 450c, then slower after that, looks like it wouldn’t pass 550c at all, but can’t say for sure yet without any real hills to play on close by. The 5.5cm was quick to hit 600c, then continued to slowly rise to 700. (Full load fuel was bench tested at 124cc).

I wouldn’t say the motor pulls any harder at lower rpms, but it does seem to go harder above 2000rpm. I’d possibly go as far as to say that it’s as quick on the 34” tyres as the 5.5cm setup was on 31” tyres.


So based on the above, the twinscroll works like it’s meant to. In this case a bigger turbine housing is able to spool up like a smaller housing, but flow better at higher rpm. I don’t think much exhaust is getting wastegated. I plugged the wastegate actuator line and only got maybe 25psi (about 5psi more). I guess the egt is too cool to produce more boost? The exhaust doesn’t seem as loud on full load as the 5.5cm, when you could really hear the difference when the wastegate opened. The big gain then with this setup seems to be gaining headroom to add more fuel whilst keeping egt safe.

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Nice work!


So from someone with a stock 13BT manifold, it seems like the 5.5cm still might be the way to go.
 
8.5cm twinscroll he221w initial testing:

Spoolup is almost as quick as the smaller Wuxi he221 with the 5.5cm housing. Looks like the boost gauge starts to move at about 1200/1250rpm. Seems to hit 10psi around 1500, and 20psi at 2000rpm. The Wuxi 5.5 started seeing boost maybe 100rpm sooner, and the 7cm about 150rpm later.

Cruise egt is about 20c lower than with the 5.5cm (340c at 100kph vs 360). Cruise boost is maybe a few psi less (just under 10psi, the 5.5cm about 12psi).

The big change is full load egt. Down by at least 100c, maybe as much as 150c. Climbs quickly to 450c, then slower after that, looks like it wouldn’t pass 550c at all, but can’t say for sure yet without any real hills to play on close by. The 5.5cm was quick to hit 600c, then continued to slowly rise to 700. (Full load fuel was bench tested at 124cc).

I wouldn’t say the motor pulls any harder at lower rpms, but it does seem to go harder above 2000rpm. I’d possibly go as far as to say that it’s as quick on the 34” tyres as the 5.5cm setup was on 31” tyres.


So based on the above, the twinscroll works like it’s meant to. In this case a bigger turbine housing is able to spool up like a smaller housing, but flow better at higher rpm. I don’t think much exhaust is getting wastegated. I plugged the wastegate actuator line and only got maybe 25psi (about 5psi more). I guess the egt is too cool to produce more boost? The exhaust doesn’t seem as loud on full load as the 5.5cm, when you could really hear the difference when the wastegate opened. The big gain then with this setup seems to be gaining headroom to add more fuel whilst keeping egt safe.

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Are you going to get it on a dyno again would be interesting yo see how that changes.
 
Are you going to get it on a dyno again would be interesting yo see how that changes.
Am intrigued by the fitment of the twin outlet manifold on the 13BT. Hope to fit my Eclipse split pulse manifold this Friday to my 1HDFTE. Had to sort out a blown inlet manifold gasket last week and now the A442f is getting a birthday with a flush, new filter and 5 new solenoids. The transmission although tweaked 6/7 years ago with shift kit and uprated torque converter is probably the weakest link once the boost gets back to through at the levels I am expecting (approaching 30psi). Keen to see if there is any perceived earlier boost response from the split pulse set up. Only able to ascertain that off my ass-dyno as my tuner is 3 hours drive away in New Plymouth. Might be able to work it out from my pillar mounted boost gauge on a rough and ready basis.
 
Yup hopefully will put it back on the dyno. Won't be going to the same dyno sadly as I've moved from Auckland to Palmerston North. I'm not so curious about the comparison to drive back up there, did that drive enough times moving all my stuff down with a trailer.


So from someone with a stock 13BT manifold, it seems like the 5.5cm still might be the way to go.
I think so with altitude being a factor.

@TLEXAS Are you switching turbos at the same time? It would be interesting to see how twinscroll compares using the same size turbine housing. Eg my 8.5ts seemed to spool 150-200rpm sooner than the 7ss. Would a 7cm ts have spooled 400rpm sooner, at 1000rpm?
 
Yup hopefully will put it back on the dyno. Won't be going to the same dyno sadly as I've moved from Auckland to Palmerston North. I'm not so curious about the comparison to drive back up there, did that drive enough times moving all my stuff down with a trailer.



I think so with altitude being a factor.

@TLEXAS Are you switching turbos at the same time? It would be interesting to see how twinscroll compares using the same size turbine housing. Eg my 8.5ts seemed to spool 150-200rpm sooner than the 7ss. Would a 7cm ts have spooled 400rpm sooner, at 1000rpm?
Trundle is across in New Plymouth is not too far away from you there in Palmerston North. Chris is real good and did my dyno work and got my Unichip sorted. No change of turbo from Red wheel G Turbo just yet. With my blown inlet manifold gasket sorted last week and now boosting 25psi plus, 5 new solenoids, new filter and oil in the slush box and the split pulse exhaust manifold getting fitted later this week I may not need the turbo change I was looking at previously. With the split manifold it seems a pity though not to fit up a twin volute BW7163 to take full advantage of the pulse separation.
 
I haven't measured my compressor wheel, but that turbine wheel matches mine. It's not just the wheel sizes though, the centre section is different where it fits into the turbine housing, you wouldn't be able to swap turbine housings between the regular he221w and our 'small' version. It's basically a totally different turbo.

I've had another change of mind since my last post, and have ordered a 'large' he221w from Trundles here in NZ. I spoke to Chris on the phone and he confirmed the dimensions of the he221w centre section where it fits into the turbine housing, and they appear to be the same as the td04hla, totally different to the 'small' he221w which he also sells (and he is aware that they're totally different turbos).

The small he221w has been a great performer for me, but ever since having my truck on the dyno I've been sure the turbine housing was too small at higher rpm. Now I know it's probably the whole turbo that's a bit on the small size. Chris Trundle said he would expect a 3.4l motor to be choked pretty badly by it. Hopefully I don't lose too much early spool up going to the larger turbo.
Holset labelling seems up the sh!t lately ive seen 211/200 and 221 all labeled as 221 for some reason. You need to check wheel size when ordering
 

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