303Turbos

Hi kids:

Working on becoming a sponsor on this site, but I thought it would be fun to find out what everyone's dream hx series holset turbo would be so I can find out if it can be easily built.

I have seen dyno charts of a hx35/12cm at Mac Autosport in Parker, Colorado, and it looked pretty choked out: the peak torque came and went very very quickly, but the HP number was respectable. To me, it looked like a turbo that made very unusable power due to the turbine housing size.

So, the question is, what is the best streetable hx series turbo? Has anyone had really good luck with a particular combination? Really, I don't want to put the time, effort, and money into building and marketing a turbo that is crap and that no one wants.

My thoughts were this configuration http://www.turbointernational.com/pr...turboModel=587 with a 16-18cm turbine housing, externally gated ONLY (the wastegate flapper is pretty small on the internal spec units, so the ability to prevent surge/overspeed is very limited and so is the ability to upgrade the flapper door) as a street turbo. But I don't actually know what's best.

I used to shake my head and think people that used holset turbos were dummies: the turbo was not designed for small displacement gas engines, the people who were buying them were paying $500 for a used turbo, and the rotating assembly seemed very heavy. I am now certain that this idea was totally wrong: the hx35 is pretty awesome and I want to see what it can do.

Brian

crazyassbill

I run a holset he351cw, waste gate valve welded shut, and 4 inch open down pipe. I love it but turbo seals are going. Fast spool, good top end.

303Turbos

Yeah that turbo is pretty awesome: the inducer is pretty big and the c/housing a/r is bigger than a normal hx35. The problem with those is that no one can get turbine wheels or compressor wheels for them: a $1000 CHRA from holset is the only option if the turbine shaft is too worn or if the compressor wheel is nicked, so the ability of anyone to make or sell these is pretty much nill, because a GT3076r is pretty comprable in specs, performance, and price.

I really want to find the compressor covers and bump them out to take the HX35 described above. Do you have any dyno charts? I really want to see what that smaller hy turbine wheel in the 12cm housing does even though I can't get the hy spec parts.*


*I know, it's a h3351cw, but it runs the hy35 turbine wheel.

crazyassbill

I blew up the old engine, cracked three sleeves. I have a fresh build about to come out as soon as my ostrich gets here. Rods and pistons poor mans type r, blox cast turbo manifold. I'll let u know what it makes on dyno day which is coming up in a few weeks.

303Turbos

That's probably not good if the turbo was on the engine at the time-the last he351 I saw was from a Cummins that spun an oil filter off while it was running down the highway.

ostrich?

wantboost

iTrader: (2)

I have an he351ve here i've been debating about fiddling with. The DSM guys run these with amazing results... 10psi by 2600rpm in 4th from a roll, with the vgt going wide open after seeing 26psi by 4500ish

303Turbos

I don't like those because you cannot feel shaft play on a Holset turbo, so you never know what you are getting. If you can feel shaft play, the turbo is done, but if you can't, it means NOTHING. Trust me, I have taken apart more than a few Holsets that felt great and had bearings that were completely burnt up.

What I see on the Holset units is the VGT assy. getting sooted up so that it does not respond quickly enough to slow the rotor down, so the VGT turbos have very very badly beaten thrust bearings or they have wear to the exducers that is invisible until you take the c-cover off. Sometimes the VGT turbos (hx40 sized commonly) kiss the compressor housing after a surge/stall and the turbine housing snaps.

Big problem on the ISM engines-the thrust parts get beat because of overspeed to the point that the compressor wheel just goes wherever, the turbo comes apart, and the $4000 intercooler fills up with oil. It's a problem with the VGT system in all holset vgt turbos, so thrust bearing wear is also always a problem.

I just don't like the DSM approach of putting worn out parts on something, even if the results seem to be awesome. If I could get those turbos new for less than $3000, I would sell them for sure. I am willing to bet, too, that the efficiency range of the rotor assembly ends at about 26psi, so any gains after that are marginal. I would be surprised to find out that Holset engineered that turbine wheel to be the most efficient in a gigantic sized turbine housing. More likely, the housing was designed to minimize rotor speed under high exhaust pressure in order to maintain constant boost: the VGT system, used by the DSM guys to spin the rotor, is designed to slow the rotor down instead.

The hx35 series turbos make full boost at 4000rpm on 1.8 liters, so is the he351v that much better? I don't know...

EDIT: AFAIK, no one advertises a bearing kit for the variable vane turbos, so no one has ever even put new bearings in these things?

RICE POLICE SIP

iTrader: (2)

I'm running an HY35 on my SOHC 1.6 on stock sleeves.. 23lbs making 360 to the ground... I was actually wanting to come up with a setup that might flow more air but spool just the same.. maybe an HY35/HX40 combo.. not sure if it's possible but thought it might help a little...

wantboost

iTrader: (2)

they use the same parts as an hx 40, compressor wheel is identical to the 8 blade super hx40 wheel.

I got mine new for 125 on ebay. guy had it mislisted = score for me. same way I got my IHI RX8 ceramic ballbearing CART turbo

wantboost

iTrader: (2)

you need street vids of your hood exit, kthx

mar778c

iTrader: (1)

Search for threads started by member mar778c. He has recently put together a project using a H1C. It may be of interest to you.

RICE POLICE SIP

iTrader: (2)

LOL i'll try and get one soon... Just gotta swap out my trans first :/

wantboost

iTrader: (2)

referring to yourself in the 3rd person?

mar778c

iTrader: (1)

Yeah, because I can't link the thread from my phone.

crazyassbill

when i got mine it had shaft play, i had problems finding bearings for mine, luckily a friend of mine is a machinist and made me a set.

unlimited[nyc]

hx series turbos are very good turbos....we made 607 on a built gsr with and hx40 at 28psi
we also made 543 with another hx40 with a stock k24 on 15psi
last was the hx50 that we had to modified the back housing to make it work we made 717
at 32psi on a 81mm built gsr
I would say the hx50 is the best turbo but it is hard to find and the back housing has to be modified.

fmfkid250

I have used all of the following holesets on hondas
hy35
hx35
hx40
he341cw
he351cw

What it comes down to is the motor setup. cams ect. I had a single cam on a he341 race gas put down 410@22psi. 20psi by 5000rpm

303Turbos

Which HY35 is it, the one with the vband outlet from the compressor cover or the one with the 90 degree elbow discharge? The vband unit has a larger compressor wheel but a smaller turbine housing, and the 90 degree unit has the smaller c/wheel (71 vs 78mm major) but the 12cm housing.

With hybrid turbos, the real problem starts when you make a turbo that has a compressor wheel that is much larger than the turbine wheel. These turbos will surge pretty badly and not do well at high RPMs vs a turbo with a properly matched turbine wheel/compressor wheel combination. That's the disclaimer. The hy turbos can be upgraded.

The hy35 wheel is perfect for 2 liter and under displacements, but the only place to get them is China. The big Holset house out here 'has never carried and will not carry' the hy35 wheel..

303Turbos

Do you have any kind of link that lists the specs of the super 40 wheel? I would be surprised if that were true-the he351cw wheel does not have a very big exducer. It would be great if it were true, because holset has assigned a specific number to the he351cw compressor wheel, and it doesn't cross to anything but that turbo. The c-wheel is about as available as the turbine wheel.

That's why I like the forums, you guys are like detectives.

303Turbos

Yeah no one knows what is in that turbo but a few specialists. It runs a hx40 thrust bearing setup and hx30 bearings. I have seen a lot of them recently.

303Turbos

The hx50 is so easy to find-it is as common as all of the others, but most over the road trucks don't sell their take-offs on craigslist. Guys like me get them.

how was the spool for the numbers vs a gt35/gt40?

303Turbos

what was the peak torque?

da_dude

I made 420whp 348tq on hy35 @ 27 lbs on a d16z6 on e85.

wantboost

iTrader: (2)

the cw and ve use different wheels, the ve being the larger of the two

VE Wheel dimensions.
Turbine
EX 2.357 ~60mm
IND 2.755 ~70mm

Compressor
EX 3.38 ~85-86mm
IND 2.37 ~60mm

exducer size is only a rough way to figure out max flow... even with an 86mm exducer the turbo still flows 65lb/min at its peak

303Turbos

The compressor wheels have the same part numbers stamped on the back of them: I have used take-off compressor wheels from the ve and put them on the cw so that my customer could ruin the turbo and not wait for new parts to come in to do so. (FYI, don't ever run a turbo with four loose vband clamps)

The turbine wheels are different, with the ve having the larger of the two