kS12

I wont find out how it works on my rb25 tell spring, but i might swap out to gt35 with internal wastegate.

rb20240sx

You're going hx30 on your 25? I just finished rebuilding mine. And for the first time ever have really seen what absolutely ZERO shaft play looks like.

__________________
95 SE Serengeti sand- RB25 Neo

lowrider260

Well, to be quick and dirty, it takes 450cfm to make 300hp. The HX30 according to the map posted flows a maximum of 370cfm.

Quite frankly, you would be better off running a gt28. It will actually flow 482cfm @6500rpm @10psi. Of course these calculation are rough at best but they do give you a good idea to go from.

lowrider260

Here is a map of an HX35 that could be loosely applied to both the 1jz, and the Rb25.
This is reaching full boost at 3250rpm. If you anticipate it to spool later, just move the the intersection point of the diagonal and horizontal line to the right.

robots

Dude, I think ur calculations are a bit off.
All turbos are basically the same. Its just compressor/turbine wheel size and ar on the turbine which really tell the story.
Lets say we got 71mm compressor exducer be it on t3/t4 or mitsu or holset or even gt2871.
Basically they will be all capable of similar flow.
So no way a smaller GT28 will flow more air. GT28 exducer is what 60mm?
Also the turbine will flow more on HX30.
I don't believe that lower trim on HX30 compressor will reduce the flow that much.
Maybe a few lbs at most.

As for the HE351, can you do the 62mm/86mm compressor plot ? What do you think the flow be on 20psi ?

lowrider260

Are they now? So the only thing that affects flow on a compressor wheel is the exducer size? Not the ratio between the induced/exducer, the compressor housing design, or the blade design of the compressor wheel?

Turbines:
Well sir, we are plotting compressor maps. The two significances that the turbine housing plays is where the "boost knee" is drawn on the graph, along with the fact of restricting maximum flow via back pressure if they are too small.

For comparison, compressor trims:
HX30 has a 44mm inducer and a 73mm exducer. The trim of the turbo would then be ((44*44)/(73*73))*100 which equals a 36 trim compressor wheel.

Gt28 has a 46.5mm inducer and a 60mm exducer. The trim would then be ((46.5*46.5)/(0*60))*100 which is a 60 trim compressor wheel.

I can post a plot of the same engine on both the gt28 and hx30 to illustrate my point.
I'll try and find one, the last time I looked I couldn't find a HE351 map.

robots

This is your thread, and I have no intentions in changing that.
What I believe is compressor trim can't effect flow that much. And even garrett states, that its not a rule of thumb.
Smaller trim should mean its higher pressure ratio capable, right ?
What I get to is. Bigger wheel turbo with a similar hot side shouldn't get u less horsepower. Its not right haha )))
I just want to belive that way probably haha. Will wait for your posts.

lowrider260

Yea, its a tad bit confusing. Anyhow, here are the hx30 and gt28 maps for visual reference. Both use the exact same flow numbers for an Rb25, with the maximum boost being achieved at 3250rpm.

casman86

If you search on driftworks, there's someone running a hx30 on a sr20, and his friend running a hx35. The hx35 user complained about lagginess for drifting, but loved the power delivery of the hx30 on the other car. I like results a lot more than compressor maps. I just got a hy35 that I'm rebuilding for my ka-t. I can't wait.

rb20240sx

Ya I hear good things about them on sr's. I just posted hx30 on ebay I'm going to get the hy35 or He351 for my rb25 instead.

__________________
95 SE Serengeti sand- RB25 Neo

90240sx07

^^^^ how much for ur hx30

robots

holset website states, hx30 flows 0,35kg/s at 3:1pr, about 30psi of boost. converting kg/s to lb/min will give us calculated compressor flow of 46.29lb/min. also check out trust turbo table at trust jp website. they would have approximate hp reading for every turbo.
there will be interesting turbos there with different compressor trims and turbine sizes. You should check it out. Maybe the compressor map u have for hx30 is a bit off? I believe there are several hx30s out there, and they would have different maps.

240sxluver4life

Just so everyone knows, trim equals (inducer)2*(exducer)2*100. I have an hy35 on my kade. Havent started it yet but if i remember correctly i calculated the trim at 54 lb/ min.

smelly240

I think the size of a HX35's compressor cover is deceiving. Its not a very big turbo as far as power output goes. They flow less than a 3076 or a 5557.

I ran them for a long time when i was younger... even ran a he351ve a few years ago (with the vgt working completely).

An 8 blade is ok if you are looking for 400ish - but a hx30 is probably too small for your average sr with cams/intake manifold.


Trim isnt measured in lb/min btw - its simply a number discribing the relationship of the size of the inducer and exducer. Lb/min cannot be "calculated" without extensive testing - it needs to actually be measured.

__________________

HREs on a S13 - check, 6262 - check, Girlfriend.... - nope

robots

Ok, back to pc.
Here it is: http://www.trust-power.com/spec_swf/02turbo/Syogen.swf


Since Trusts are ex-mitsu diesel heritage. So its good info.
There are various trims for compressors. There is similar one to HX30 one.
TD06 17C or smth. Trust states it can push 300-380 hp.

Can we anticipate one's turbos hp rating ? Yeah.
Will it be 100% correct - no.

I usually just get a list of turbos compressor sizes and try to find a close match.
And see read about that turbo and real life results if applicable.

Hope it makes some sense haha.

Bring on some more results.

Maybe we should make a list of HX30 variants and HX35, HX40 with their compressor maps here ? Make the thread more educational ? Maybe even post some youtube vids with spool and stuff ? What you guys think ?

There are 2-3 HX35 I know about. Exducer 76 and 82. Inducer also runs differently from 52mm to 54 and 60mm I believe.

It will all net you with different results.

rb20240sx

^ I think the youtube vids would be a good Idea.

I just found the holy grail of info on these suckers Turbo Mopar Forums - Knowledge Center: Guide to Dodge Cummins Holset Turbochargers
I think I'm definitely going with the he351cw.
Anyone know if the he351cw is a t3 flange. I know the he351ve has a bigger flange but can't find much on the non vgt housing?

__________________
95 SE Serengeti sand- RB25 Neo

josephin510

Love were this is going I plan on giving my Rb25 and my 1jz some holset goodness.

__________________
Trade my Rb25 for some wheels.
Buy my Sc300.

robots

Maybe post results already? Anyone? haha

lowrider260

Well... Here is a quick video of my car. This was before I had did the final porting on my wastegate. I was short shifting as soon as the boost hit 15psi. I need to make another video once I reassemble my car from its winter makeover.

260z holset - YouTube

robots

5th and 4th gear boost pull with a HOLSET HY35 - YouTube RB25 HY35
Holset Spool - YouTube VW 2.0 8v

lowrider260

robots

Hmmm, maybe more discussion ? Any SR or KA results ?
I know there are more people areound who want 400rwp for cheap))

rb20240sx

That Z sounds awesome. How big did you port the wastegate, and did you stick with the stock flapper? Also how much boost are you pushing now, Any creep issues?

__________________
95 SE Serengeti sand- RB25 Neo

lowrider260

Thanks! unfortunately I did it in stages, but the final porting did the trick It holds 10psi steady. As most know the hx35 and Wh1c have a divided t3 exhaust housing. It also only has the wastegate pulling from one side of the divider. Sooo, I cut the divider out all the way down to the wastegate hole. Then ported the hole and used the stock flapper, It still creeped a little. The be all end all was a forged performance 34mm flapper and porting to match. Like I said it holds 10psi now. I'm currently running 15psi, but I would like to turn it up to 20psi with some meth injection. I'll also include a few pics of the divider removed and the fp flapper install.




Stock wastegate hole and flapper:


Stock VS. fp 34mm



Unshrouding the flapper a bit, and you can vaguely see the difference in the wastegate hole size:

robots

Don't stop, keep it going !
Nice work on the wastegate hole! What actuator did you end up using ?
How is the boost build up with the actuator ? Noticeably worse than with external wastegate ?

slydin240sx

Could you not just weld the internal waste gate shut? and run a external waste gate?
I don't know much about turbo's but one day would like to run a holset hx35 on my KA. So any information I can get would be great.

rb20240sx

^ You can run an external but there $200++work. And yes lowrider what actuator are you using? I looked at the prices of those 34mm flappers, and lets just say I'm a cheap skate.
I wonder if I could cut and modify and exhaust valve to work, and if it could take the heat? I don't see why it wouldn't.

__________________
95 SE Serengeti sand- RB25 Neo

lowrider260

The actuator is a factory piece from a mid 80's 300zx turbo, that I had from my from my first turbo. I cut the actuator rod down, rethreaded it, modified it to mount on the holest's exhaust housing, and adapted the original wastegate arm.
You can kind of see it in this picture.


The exhaust valve is a good idea, it's designed to withstand the heat in the combustion chamber. The only problem is that the exhaust valve is made to seal on the top side and most exhaust valves aren't flat on the bottom, where you need it in a wastegate flapper application.

casman86

Way less work to just have a wastegate flange welded to the manifold. You can find used Tials and other name brand wastegates for $100. Oh and SLydin240sx, everyone welds the internal gate shut when used on KA's. Every t3 manifold available has an external wastegate flange on it.

slydin240sx

Yeah, true.