RJwaggs

Does a flow rate of .35(kg/s) do anything for ya?

Tom-Guy

Actually, they most power I am aware of one pushing is 558 whp @ 30 psi on a DSM. Which is pretty fucked, the map goes higher than 30 psi for a reason, there is no excuse for not tapping 600+. It's optimized for high pressure ratio boosting w/ efficiency... if you're looking for OMG 300 whp at 9 psi on your GSR with Full-Rice kit, well, walk and shop baby walk and shop.

When you consider Holset's blurb is the HX35 is good for .46 kg/s (75 lb/hrs) @ 3.0:1 pressure ratio... well, what amount of boost is 3:1 PR? Anybody care to speculate?


They aren't a secret. Holsets just aren't fluent in the gasoline world, compounded by most of the aftermarket enthusiast guys who've called Holset and asked Q's not pertaining to diesels have found themselves hung up on, or email communication suddenly goes ignored. I could go off on a tangent about how wierdfuk diesel guys are, they really aren't at all interested in going fast so much as they are in something "that pulls." Their eyes glaze over when they say pulls. Maybe you've tried talking to a few, like I have...

But, yeah, Holset uses cm^2 nomenclature which is more accurate than A/R as it tells the actual aperature size at the point of intersection with the wheel... the actual shape of the "funnel" that the scroll is can them be optimized for various flow characteristics as it no longer needs to be a homogenous Area/Radius throughout, and the actual orifice size at the point of intersection of the wheel tells us everything we need to know about flow/mass/velocity as it pertains to spool, etc.

Housing types aren't secret, the info is just not publicly published. A lot of the Garrett stuff isn't, as well, but some people are good(ish) about disseminating the information to the aftermarket... but you notice between Precision, Turdbonetics, Innovative, etc, they all use different terms or names for the same part they all bought directly from Garrett. A number of the Holset compressor maps have been floating around the interweb recently, and you can derive a fairly good idea of where your point of spool will be based on anecdotal information. Not that it's going to be the same for two identical engine/turbo combos that have different manifolds, sometimes (Honduh world) it's as much as 1500 rpms spool difference!

If we haunted diesel forums, I am sure we'd have a better grasp, depending on our ability to infer aforementioned anecdotal evidence on the gasoline applications we are familiar with.



Flow rates are "the same thing" as the HP ratings Whitey said he doesn't care about. :P

Well, there are 360 seconds in an hour, and 2.2 lbs in a kg, so .35 kg/s turns into 57 lb/hrs General rule of thumb sez 570 whp!!

http://www.holset.co.uk/files/2_1_1_2-HX30.php

I think the Holset blurb on those is inaccurate, as that is HY35 power territory... there is a compressor map handed around for the HY35 that states it is for HX30 (Honda-Tech FI forum thread somewhere on or about page 24-2, although the poster said that this is not true. BUT it makes me wonder if there aren't different HX30 compressors?

Or maybe not... the HX30 wheel *is*... "shallow" for lack of a better word, but it's OD is about as large as HX35. There's a lot of it covered up by the compressor housing. And the Holset blurb claims .35 kg/s @ 3.1:1 PR, so it's map is good a bit above HX35...

---- it, I may modify the STD manifold for the red car to accept external wastegate and run the HX30 on the high CR SOHC. It's freshly built, no reason not to, y0!

CyberManiaK

Excelent.. that was the info i was looking. Now if the holsets turbo made that kinda of torque i hope my trany can handle that amount

As soon i have it done my car i will put some dyno sheets here to share !!

Thanks for all that info.

Tom-Guy

I wish I knew more about the turbo I owned. I feel like I gave you some good information, but if you read close I gave you a lot of speculation and guesswork, too.

Pick apart everything I said before you go with it... I have a problem with making ideas I'm fascinated with sound like a sure thing, when they're NOT.

Reddy

Lol, I said "generic statement," I have no idea what an HX35 was rated at HP wise.

Tom-Guy

.46 kg/s = 75 lb/hrs.

At 3.0:1 pressure ratio.

3.0:1 PR is what psi?

Wouldn't it be funny? If HX35 is actually 750 whp turbo?? But nobody has the ***** to push that high because OMG HP PER PSI is all that matters??

Ben Strader would laugh at such volumetric efficiency bullshit, although he's required to teach it because, and I quote, "It's what everyone expects me to teach."

CyberManiaK

Thanks one more thing can you please give me all the stamped numbers you have please ?

BTW i will like to push it something like 17 psi for the street and 25 psi on the drag track.

uhm if i'm not wrong 3.0 PR is 29.4 psi

Tom-Guy

I'll have to go back to the turbo and look *real* close, it'll take a couple days. Somebody ground on the number tag when trying to grind the "HOLSET" raised logo off the compressor... I had to squint real hard in bright light with the turbo cocked to the side to read the numbers. They were still legible, but turning the turbo 1/16" too far made them blurry.

I ordered a kit for it from a Holset dealer in Johnston City, TN... they took forever about ordering/shipping it to me, and then the thrust washer was completely wrong. I ended up re-using the original thrust washer as it was fine - I guess the whole turbo was fine, but I'm ---- and only have $225 in it as it sits. Had too many used turbos go belly up on me.