Holset Turbos, PART 9

[FirstCarIsA GSX]

Do I recall you saying the batmowheel actually logged less total Lb/min than the 6 blade cast wheel as well?

If we're saying even the batmowheel isn't too big of a difference with a standard cast wheel. What type of differences are we seeing between the regular billet holset wheels and the standard cast wheels? is there a big enough of a difference to switch or to even pay extra for it?

 

[Archer Fabrications]

I dunno what others are getting with the cast wheel but i see 27psi by about 4200-4300rpm on my bolt on hx40 billet 7 blade. Benefit of billet is spool time.

 

[red_devil]

I dunno what others are getting with the cast wheel but i see 27psi by about 4200-4300rpm on my bolt on hx40 billet 7 blade. Benefit of billet is spool time.

That’s not really true; most evidence shows there is little to no difference in spool time. The benefits are from design changes and or tweaks to the compressor wheel, and also it’s tougher and less likely to get damaged when not running an air filter.

 

[Archer Fabrications]

In some cases like HTA the wheel is lighter and makes the compressor spin quicker due to less weighted rotating mass. I can't say for the holset though cause i haven't weighed the billet 7 blade or a cast 7 blade compressor.

 

[FirstCarIsA GSX]

In some cases like HTA the wheel is lighter and makes the compressor spin quicker due to less weighted rotating mass. I can't say for the holset though cause i haven't weighed the billet 7 blade or a cast 7 blade compressor.

Has anyone done a back to back comparison? Or at the very least compared logs between the two? This type of info would be very beneficial to the community. Especially with how popular holsets have become. We might shed a new light on the advantage of the billet wheels or possibly dispell the billet wheel myth with these turbos.

 

[Archer Fabrications]

Has anyone done a back to back comparison? Or at the very least compared logs between the two? This type of info would be very beneficial to the community. Especially with how popular holsets have become. We might shed a new light on the advantage of the billet wheels or possibly dispell the billet wheel myth with these turbos.

people will just direct you to the holset results thread, id do it if someone wanted to donate a cast 7 blade wheel.

 

[FirstCarIsA GSX]

people will just direct you to the holset results thread, id do it if someone wanted to donate a cast 7 blade wheel.

Still haven't seen any sort of logs comparing the two. Anything out there anyone find?

 

[Archer Fabrications]

Look through the other 8 threads to s of logs, ive got some if you want .

 

[airmail96]

airmail96 is that T3 or T4 housing? Reason I ask is because I know that holset made a hx40 18cm t3 TS housing which is supposed to rare. Did redjack make you're o2 housing as well?

Yes the housing is a T3, it also has a billet compressor wheel I picked it up from justin awhile back his friend was running it on his RX-7.

 

[Archer Fabrications]

Whose goin' fast this summer with their holsets!? I wanna see some killer hx35 and hx40 numbers!

 

[1glaserfwd]

Yeah hoping for a high 10 sec slip this summer for sure!!

 

[WES_393]

Hoping for 500hp at least, which should be a breeze with my 60mm 8-blade H1E.

 

[Archer Fabrications]

Hell ya! Im shooting to get kicked off track for no cage mid 10s

 

[beansblacktsi]

hoping for mid-high 9s out of mine this year!

 

[907dsm]

Beans I know you went to the T4 TS setup last year but what else did you change for the upcoming season?

Alex

 

[beansblacktsi]

Beans I know you went to the T4 TS setup last year but what else did you change for the upcoming season?

Alex

freshened up the trans and bought some bigger injectors. That's it.

 

[mechanix565]

so today i was given a perfectly working small h1C off of a friends 1st gen dodge ram cummins, i took it apart cleaned it and promptly put it on the shelf and began looking up parts haha. but heres my main concern im looking to get about 450 wheel in the future and thats all im ever gonna want because the car is gonna get driven alot and i dont want it breaking constantly. Can the small H1C flow enough air at any given PSI to support 450 wheel in either the BEP housing or the 12cm t3 housing (i have the 12cm) if it will it would be awesome the motor im building is a 2.4l dohc with 272 cams, weisco HD's eagle rods , BSE kit blah blah blah, so long story short will this turbo get me there?

 

[WES_393]

From the Holset thread:

I have the big h1c. It comes on the INTERCOOLED 1991-1993 cummins pickups. It has the webbing for MWE but no groove cut like the hx35/wh1c has. This turbo I term the big h1c because it has a 54mm compressor inducer and same exducer than the 8blade hx35/Wh1c. The other h1c is the small h1c found on the NON-intercooled cummins pickups. This has a 50mm inducer but only 7blades and has no webbing for MWE. Less blades helps flow, but so does a larger inducer diameter. The most whp ever recorded on a gas 4cylinder with the small h1c was done on a KA24 nissan: 411whp. Since the big h1c has a 4mm larger inducer and the same turbine wheel as the hx35, it is safe to say that it flows enough for between 411whp and 500whp. The diesel sources state that it flows SLIGHTLY less than the early hx35. So 4lb/min less than the 8blade hx35 puts the flow of the big h1c at 48-49lb/min right where a 50-trim or 20g is. The small bep housing is all that's needed to get the most from the compressor and the spool speed is 20+psi by 3500rpms.

 

[mechanix565]

missed that part. so 411 is the max ever put down on a small H1c that was on pump it looks like could be a bit better on e85 perhaps.

 

[Archer Fabrications]

Can someone look at my log in the results thread an tell me why the hell my boost doesnt hit 30psi til like 7k?

Waste gate spring is 19psi hx40 bolt on housing

The waste gate opens at like 26-27 psi at 4kish and i have it set for 30 but it doesn't hit 30 til the end of the pull. Doesn't go over where i want it so i wouldn't call it creep. Anyone else experience this with their holset? Or does it pretty well flatline to your set boost?

Stock parts i still have are listed in results thread also.

 

[forcefed86]

I dunno what others are getting with the cast wheel but i see 27psi by about 4200-4300rpm on my bolt on hx40 billet 7 blade. Benefit of billet is spool time.

Garrett has done back to back testing of billet VS cast and there was NO benefit performance or "spool time" running a billet compressor. Assuming the billet wheel is an exact clone of the cast. Since the billet stuff is CNC milled they can be a bit trickier with blade design ( like batmowheel) and some small gains can be had. There is no reason IMHO to switch to a billet wheel unless the wheel is machined differently.

Why do you think a cast alum wheel is heavier than a billet one? Billet is more dense than the cast. One of the reasons it's stronger. I suppose the billet comp blades could be machined thinner, but from what I've seen they aren't. (I have the 6 blade hx40 billet wheel) I'm sure Justin or someone with a turbo repair shop could weigh cast vs billet comp. wheels for us.

 

[Archer Fabrications]

Yeah were not really talking about garrett here, in fp's design anyway billet=fast spool.

 

[forcefed86]

Yeah were not really talking about garrett here, in fp's design anyway billet=fast spool.

I don't think you have anything to base that off of other than hearsay BS. The FP HTA designs aren't like the exotic CNC batmowheel type designs. The batmowheel design did show some minor improvements in specific areas, but for most of us these improvements don't justify the added cost of the custom wheel.

The FP HTA designs look like a standard compressor to me. I'm sure a cast wheel of the same dimensions could be substituted with no performance loss. But then they couldn't justify what they are charging for them. Billet wheels are mostly hype from the reports I've read. Can you show me some proof or back to back testing from a reliable source that indicates any of the billet replacement wheels out perform a cast one of the same dimensions? I'm not saying they don't exist, but I sure haven't seen them.

As long as the great uneducated masses are willing to jump on the band wagon, people will continue to will pay exorbitant prices for shiny compressor wheels.

Cast vs. Billet Compressor Wheels... interesting result - Dodge Cummins Diesel Forum

Quoted reply sent straight from the Borg Warner Tech department. This is the reply they sent back when asked if they could create a billet comp. wheel.

"BW AirWerks –

In general... yes, we can make anything if you want to pay for it In the performance and/or racing world though, there is really no benefit to using a "billet" CW other than it's shinny. Basically, billet, or FMW (Forged Milled Wheel) compressors came about due to OE applications requiring them. When a turbo is constantly being cycled from high speed to low speed, the wheel becomes fatigued and can eventually lead to a hub burst (CW splits in half). Imagine the compressor acting like a big drag slick like you see on top fuel cars; during the burnout, you can see them get skinny and "grow" in height... On a much smaller scale, the CW sees this same process over and over again, and over time this weakens the wheel, eventually leading to a fracture and possibly a hub burst. Now ask your self how many times you've seen a race car's CW split in half... I have never, and I've seen a LOT of failures. Even the billet aluminum isn't enough in some newer applications and we've turned to titanium which in its FMW form, is nearly indestructible. I've heard all the propaganda surrounding the billet wheel myths: higher boost capability, higher flow, higher efficiency, etc... The higher boost capability is the only one which is true, but not because it's machined and not true for racing use. OE diesel applications using FMW compressors can run higher boost pressures more reliably simply because they are less susceptible to fatigue as they're cycled from higher speeds (required to make more pressure) to low speeds.
So, why would anyone offer a billet wheel to the racing/performance market? Couple/three reasons:
- Some people just want them because they look really nice... and are willing to pay the cost difference.
- Because it already exists in an OE production application and it's easily installed into performance turbos, sometimes they're even interchangeable with existing cast wheels.
- Applications where a cast wheel does not exist (maybe a larger inducer is needed) or production volumes are believed to never be high enough to justify tooling costs.
Are they cheaper than cast wheels? ...NO. Even in high production volumes, a billet wheel will always be more expensive than a cast wheel. However, if a company wants to make a compressor all their own (not using an existing "big" turbo manufacture's wheel ie. BW, Garrett, Holset) it would most likely be cheaper as they would have to tool up to make all the cast versions. If a company makes a mistake in the design of a billet wheel, they can simply keep changing the program until they get something that works... The OE manufacturer does all the development work up front to arrive at the best possible design for what's needed. Once the design is finalized, a "master wheel" is machined and used for the tooling master... that's right, all cast wheels get their start from a very nice billet wheel that when tooling is made, creates the same exact performance characteristics in a much cheaper and faster to produce cast version. Phew... Sorry for the long-winded explanation, but hopefully this helps explain why billet wheels exist. Short version is billet wheels are no better than cast wheels for any performance or racing application I'm aware of... but they sure do look great!

 

[LandSpeed-DSM]

Yeah were not really talking about garrett here, in fp's design anyway billet=fast spool.

forcefed is correct.

Billet only means billet.

Whether the machined billet version of a certain wheel weighs less, has more weight removed from the major diameter, etc. is down to the individual wheel design vs it's cast counterpart.

Billet wheels are indeed denser, and they are more useful for higher stress applications.. like very high PRs/shaft speeds where the cast wheel may come apart or deform.

As far as why you are having trouble building 30psi.. you may have an exhaust or boost leak somewhere. The seal on the wastegate may be compromised, there may be excessive back-pressure from a collapsed flex-section in the downpipe for example.

There can be any number of reasons. What have you tried so far besides commanding more boost? The bolt-on housings sometime have casting flashes that can snag, hang-up or rub the internal valve.

This was the case with my BEP housing initially, till I bent the actuator rod to push the flapper away and ported the housing to clearance things.

 

[Archer Fabrications]

Im not gonna read forcefed's novel, but yes i know the definition of billet means of a solid piece of metal, which makes the wheel stronger, stronger so that someone can or could make thinner blade profile design as far as i understand. Thinner blade design = weight loss. Maybe not necessairly in oe applications. But id like to see a 35r vs a 35r hta wheel weighed. Doesn't have to be a 35r but of the se caliber comparison. I think you are correct in te case that cummins may not have made any changes to their cast vs billet, but id also like to see the weight difference. I wouldn't expect to see any change in weight necessairly from an OE turbo hx40 cast vs billet but i bet if you do compare garrett
Wheel vs hta there will be a weight difference there.

As far as my issue. Im using an external wastegate. I need to do a BLT for a sanity check. I think i just need a heavie spring perhapse so the gate doesn't open as early. I feel like im loosing pressure cause i opens to soon. Even though i have a MBC. My exhaust is not colapaed at all. Im switching to t3 at the end of the month when i get my manifold so we will see if its just something with the bolt on housing.