Piers New HX-50 hybrid turbo "tested"*-

[Roger rodbolt]

Chris,

Good report, sounds like you'll be ready for the truck pulls?

Larry

 

[Chipstien]

It certainly is a beautiful turbo. Oo.

 

[Forrest]

Perhaps the new version with the smaller exhaust housing will fix the towing issue.

 

[Piers]

Forrest, there is no smaller housing coming, only bigger. This turbo was never designed for towing, at least not big stuff, it'll handle little Airstreams okay, but not the big Teton triple slides The HX40 is still a better alround daily driver, towing/weekend warrior turbo. We are altering the outlet so it'll be a direct bolt in replacement if you have a 40, no need to move your exhaust system. We are also working on a wastegate to help keep the boost to 55 and under... . maybe Jim will make up a kit like his and sell it.

 

[zjones]

I'm considering getting this turbo but I pull 26,000 lbs. (gcw 36K) & I would like to know why this turbo would not perform better than the PDR Hx40 towing?? I was told a 40 would not be good for towing yet it lowered my empty cruising egt's 100+* & lowered my towing egt's across the rpm band & also lowered my water temperature to nada. Does a 4. 10 diff ratio make that big of a difference?? 5th gear approx 2650 rpm I'm running 75mph

 

[HeberRam]

Towing

Zjones... . As I have experienced, and why I think ( so does Piers) towing small loads are "OK". The problem, with this large turbo is, it takes a lot of fuel to spool this turbo, and when you do, the boost comes on a little later then the HX-40. Because the boost comes on a little later, you create more heat (EGT'S). I have also noticed as stated earlier, there is a slight mid-range lag between 1900 RPM and 2000 RPM. After 2000 RPM, the turbo spools incredibly fast, EGT's rise to the 1200 + * until full boost is achieved, or you back off. If you are towing a heavy load, such as you are planning, more fuel will be required to get going, much higher EGT's will then be a problem. In addition, cruising with a heavy load at 1900-2000 RPM's ( maintaining safe EGT's ) will require, constant downshifting & upshifting.



That's why, the HX-40 is more user friendly in the towing applications, as it is easier ( takes less fuel to spool), the spooling comes on at a lower RPM then the HX-50 hybrid, and peak boost is lower.



The HX-50 hybrid was designed for those that have hit a "turbo wall" because of maximum safe spooling and boost levels of the current HX-40. The HX-50 hybrid, takes it to the next level, by stronger construction ie. shaft, bearings and housing to allow much higher boost levels to achieve greater unused power. There are other turbo's like the B-1 bomber, H2-e and others that are quality build for the same purpose. IMHO, Piers HX-50 hybrid doesn't lose the low end "performance lag" as the others do. This provides a better, all around , daily driver performance turbo, with strong competition potential.



Steve

 

[ob1kobi]

dyno or track time?

I am VERY happy with my Piers HX-40. I have put it in dyno contests against very similiar trucks as mine, except they had a larger single turbo, and I have beat them.



So my question is, has there been any dyno, or track time with this new big turbo? I am not really interested in twins, for now, but I am up against an air wall with my current set up. Will this new big turbo out perform my HX-40, both at the track, and on the dyno? Can I expect to gain anything, over what my HX-40 already does, by purchasing this new turbo. I do not tow, nor do I ever intend to, so I am really only interested on flat out performance.

 

[zjones]

I very rarely drive under 2000rpm if ever, does it respond as well as the 40 over 2000rpm if it does than I have my answer?? How are the egt's over 2k compared to the PDR Hx40??

 

[Chipstien]

Re: dyno or track time?

Originally posted by ob1kobi

I am VERY happy with my Piers HX-40. I have put it in dyno contests against very similiar trucks as mine, except they had a larger single turbo, and I have beat them.



So my question is, has there been any dyno, or track time with this new big turbo? I am not really interested in twins, for now, but I am up against an air wall with my current set up. Will this new big turbo out perform my HX-40, both at the track, and on the dyno? Can I expect to gain anything, over what my HX-40 already does, by purchasing this new turbo. I do not tow, nor do I ever intend to, so I am really only interested on flat out performance.

I dynoed 486 with DD3's and a Comp. From what I can see that is quite alot. This turbo flows significantly more air than a HX-40, though I have forgotten the actual flow numbers.

 

[zjones]

PDR Hx35 - 620cfm, PDR Hx40 - 745cfm, PDR Hx50/55 - 970cfm. Does anyone know what the different twin combinations flow??

 

[ob1kobi]

Thanks for the info Chipstien.



Ted

 

[HeberRam]

Zjones... To answer your question? "does it respond as well as the HX-40 over 2000 RPM?" IMHO it responds "better" and comes on much stronger, keeps building boost right through redline!



EGT's are a little higher then the HX-40, due to more fuel, boost, power=heat.



I forgot you have 4:10 gearing and this will help you in towing. Piers is also in the process of making a larger exhaust housing, a 17cm which would help in reducing EGT's. ( since this set-up has not been tested yet) no performance issues have been determined. Suggest you call Piers or AL to get more info, and determine which set-up maybe the best for your application.



Steve

 

[Jetpilot]

Anyone know the CFM ratings for a H2E or the B-1?



Doug

 

[Jim Fulmer]

Does anyone know what the different twin combinations flow??



I don't know if anyone has flow tested Twin set like mine but Al and I were thinking around 1300, might be a little more. I will tell you the draw backs on mine, the stock 35 and the 16 housing, the 35 needs the Mod and the housing needs to be bigger, I'll try an 18 and a 21 both to try and slow the little turbo down some, but before I do that I'm going to check all the air temps then change when I have some data to see were the temps go, the air out of the little turbo is HOT, but the cooler is doing suprisingly well from a touch after a hard run. I working on some other stuff R&D when I have a chance and a little cash.





maybe Jim will make up a kit like his and sell it.



If I had a truck with one around here I would build it, the problem we have discussed is getting the turbo to far out and causing clearence problems, I have one idea to maybe cure that but it sure would be nice to have some clearence shots of the 50/55 on a truck... . hint, hint!



Jim

 

[Chipstien]

Jim, I will take some pics tomorrow. Where specifically do you want pictures of.

 

[Jim Fulmer]

Think of it like this, how far out can I move the turbo away from the engine before it becomes a problem for clearance with the down pipe, I have my stock manifold I can use to simulate the angles, what it would be is a wastegate setup just like mine only upside down, then the wastegate would be pointing toward the pass side instead on the drivers side and the stand pipe for the wastegate would be 2-3 inches tall and would have to clear that huge housing and the new one also, then vent it to the down pipe, I can or anyone can egg the wastegate pipe so it's only a 1" pipe without affecting the total area this would keep the spacer from being 2 1/2 inches thick like mine. With Twins it's no big deal cause you can clock the bottom turbo were you want it.



A guy could build his own down pipe and egg it also(make it a long oval pipe) if clearance was an issue. If I had this down(had a truck to do it on) I would build it with the spacer, pipe and wastegate base flange then just send it to Piers and say try this!



If you get some pics E-mail them to me -- email address removed -- then I will look at it more and see what I can come up with before you guys start over fueling that single.



Jim

 

[Chipstien]

Well I went out to take some pics but the wife took off with the truck. :{ She will be back soon so I will take them then.

 

[Jim Fulmer]

I pulled the ones out of your readers pics to study them, give me a bit to work on it.



Jim

 

[Chipstien]

Jim, I sent some pics but I had problems. I believe your inbox has exceeded the allowable size. Empy it and I will resize the pics and resend them. What I have will be considerably more detailed than what the TDR servers will allow.

 

[HeberRam]

Better then ever!!!

Haven't had much to say, as I had to return the "proto-type" HX-50 back to Piers. The good news, is I got another one, which is close to the one for "sale" and all's I can say, this is even better then the first. . On this "new" (latest) version, he extended the exhaust housing approx. 1-1/2 inches so it matches to the HX-40 downpipe without any modifications. Next he made the oil line coming from the oil filter the same as the HX-40, so you don't have to adapt that either. And finally, he "tweaked" it some more (won't tell me what) and now the lag I talked about in Mid-Range is gone? I've only put some 200 miles on this turbo, and already I can tell the difference in Spool and EGT's. The EGT's are 50-75 * cooler then the proto-type! I really like this turbo!!! I will be going down (dropping some 3000') to Boise this weekend to see the Idaho boys, and will get a good chance to try it out at lower elevations, and push it a lot harder. Will keep you informed!