Engine/Transmission (1994 - 1998) HX-35 Hybrid

[EGaskamp]

I was wondering if any of yall like the Piers HX-35 Hybrid turbo. The reason I'm asking is that I'm getting up there in power as you can tell by my signiture, I'm also getting DV's in there and AFE cold air and I'm worried about overspooling my stock turbo because it will go up 42 PSI no problem. I want an HX-40 but don't have the cash. Would the HX-35 Hybrid work good for my set up? Thanks



Eric

 

[JGheen]

I definately understand the money issue with the HX-40, but you may just want to save up for that cuz I don't think the 35 will move the air you want even though it is a hybrid. I can't remember exactly, but doesn't the hybrid run the same compressor wheel as the 35 but with a 40 turbine wheel or is it the other way around?

With all that fuel your running, the 40 is the way to go, IMO. 370s with the grinded plate is quite a lot of fuel, what are your EGTs right now, also what size turbine are you running?

 

[Jerred]

I've got the Hybrid PDR 35 on a 14cmWG. See signature for the rest. I love the response of the turbo, but it gets hot at WOT under load going up a hill. It is very limited on the top end, even though I've seen over 40lbs boost at times out of that thing. Pressure is one thing, what you want is volume to bring down those temps. I'd suggest going one further than JGheen's advice with the 40 and look at the Piers B1, BD SuperB or HTB2. They're more money yet, but I've heard horror stories about the 40 shafts. If you're nice to it, it will probably last, but wait till you have all power under your foot, you won't be nice!! And the Hybrid 35 does have the same impeller as the 40 but the housing is the same, they just machine out the housing a little for larger compressor housing volume.

 

[EGaskamp]

My EGTs are about 900 post turbo with stock housing and everything. I just put the DVs in about 2 hrs ago, and Oh my gosh!!!!!!! I got 46 pounds of boost out of it. What is the limit for the stock head gasket?

 

[gds3076]

I have heard about 50 Ibs of boost... then you have to take care of the head gasket. I can't believe that you have it over 40ibs of boost with your stock turbo with out blowing it up! There are some good carnage pics of a some one grenading there HX-35.



I to have heard horror stories about the HX-40 shaft. If you want a real comparison you should start a poll and maybe ask if any one has experienced a failure, or seen a failure? I think that would turn up some interesting results. Just my 2 cents. . Good luck and I hope this helps.

 

[Jerred]

yeah... . be carefull with your pressures. my local guy says 45 at the max, and he's not conservative! the thing is, even the bigger turbos, like the B1, are usually set at 40lbs on the wastegate at Piers or wherever you get them, unless you request something different for a specific application. For normal use, towing and whathaveyou, 40lbs is plenty and with the larger volume of the B1's and SuperB's, you'll have plenty of air to mix with all that 370/913/191 fuel for well into the 400's (hp). Enough to melt a stock 47RE or stock clutch! and I speak from experience...

 

[Ben Rumson]

I'm on the same upward progression and the turbo is the weakest link - for now. Lemme know what you end up with and how it performs (likes and dislikes) under different situations.



I don't think the HX-35 Hybrid is enough for your setup - especially if you'll be towing a fair amount of time. Piers B1, BD would be something to seriously consider as they would be good for your power-level.



Twins would be another option to consider... but would run a bit more.

Also, you may want to look into some of the aftermarket, re-designed Cam Shafts.



These would both be more involved, and more money, but your "drivability" would be great. Significant reductions in EGT and smoke. No need to lay off the pedal when mashing it over the summit - especially if you're putting a PowerStoker in his place. If your nose to nose with him [assumption: he's empty and you're at GVW ], this is not a time you want to be forced to let up on the pedal.

 

[JGheen]

How different are the PDR B1 vs. the PDR HX-40? Obviously, it sounds like the B1 is stronger and can take a few bad barks throughout it's life compared to the HX-40. But isn't the "PDR" HX-40 assembled with a stronger and larger diameter shaft than a regular HX-40? Never called Piers on it to find out what exactly is different that he does to his.

 

[Cooker]

The shaft is the same on a PDR40 and an off the shelf 40.

 

[Deezul1]

Eric

Ask me at the dyno about my PDR35

 

[Jerred]

Eric

Ask me at the dyno about my PDR35

Deezul1,



We have about the same truck, with the exception of the 913 (215hp) fuel pump and exh housing. I dyno'd 333hp with a 14cm housing. I think I can make up some ground with 191dv's which I just haven't put in the truck yet, still on my work bench. What kind of temps did you see at 417hp? Mine were way high, over 1500deg, gauge pegged.

 

[Deezul1]

Jarred

My EGTs are not a big problem, if racing then they reach 1400 about the time I let off in 5th gear. I havnt run 1/4 mile track yet. When towing the TT the only time its a problem is loooong steep grades in high altitudes then I have to watch it pretty close and sometimes go back to 4th gear. Thats the main reason I choose a #11 plate and it seems to work well. My dyno 1 week ago was 428hp and 918tq so my combination is doing well for me. A lot of the credit goes to Cord Reynolds and Jim Fulmer for setting the arm on the plate in the right place for me as it made a BIG difference on power.

 

[Jerred]

You're right on with the throttle adjustment, I had a bear of a time getting it right with the Banks plate (which closely resembles a #8 Bosch), I even dumped the adjusting screw into the pump once. That was fun! Once I got it adjusted right with the new plate, it makes a huge difference.



I have my timing advanced to 16 deg and now that I have the #10 plate in there, it seems like it wants a little more fuel, kind of knocking a little, like when I tried to advance it beyond 16 with 370's and the Banks plate. Not totally smooth. Too much advance and not enough fuel. I will drop in the 191's, adjust for smoke (I live in CA) a little, and see if it smooths out. And then check temps and move the plate accordingly.



I'm having a prototype turbo tested on the my truck next week (can't really give details yet, I was sworn to secrecy) that's supposed to rival the B1 and such with a smaller setup for better spooling. We'll see how that goes. I really think if I switched my exh housing to the 16 I could see better dyno results due to lower temps. I KNOW there's more power there, I'm just running to hot to get to it.

 

[Jerred]

A lot of the credit goes to Cord Reynolds and Jim Fulmer for setting the arm on the plate in the right place for me as it made a BIG difference on power. [/QUOTE]



Deezul1,



One more thing, and maybe Jim or Cord can ring in on this one if they're watching: How did you adjust the arm for more power? I adjusted mine so that the throttle arm hits the very tip of the nose at the bottom of the plate profile as is first comes forward, as this is the accepted method for improved drivability (Piers website). Did you adjust yours farther up the profile or differently than that? The #10 has a large nose at the bottom and a much smaller one about 1/3 of the way up.

 

[HeavyHauler]

Twins would be another option to consider... but would run a bit more.

He's not putting out near enough fuel to turn twins. He should be at no more than 450HP with that comp on 5x5 which is not enough power for twin turbos. I'd go with a full size B1 or let me put a plug in for the Dodgezilla from City Diesel. I've heard really good results from people who are running this turbo. Call City and talk to Jason - he'll tell you exactly what you need with your setup.



1-800-950-CITY



BTW - why is this post in the 12 valve section?

 

[Vaughn MacKenzie]

The shaft is the same on a PDR40 and an off the shelf 40.

. . . but with a modified bearing and pinwheels balanced to closer tolerances. PDR40s have a good track record.



Vaughn

 

[clawson]

Check out the group buy on JR's turbo it would be great for you.

 

[Deezul1]

Jarred

Sorry to take so long to reply, kinda lost track of this thread. The arm was set about 1/4" up from the bottom on the 11 plate, that is where it starts to look like a 10 plate and it works super, very little EGT problem even with the plate full forward. The PDR 35 isnt the best solution but it sure works great for what it is and is very inexpensive, I really like mine.

 

[vssman]

I don't know what's stock for an 02 HX35/12 or HY35/9. But I was in a similar situation and went with a HTT stage 3 kit. It's easy to do yourself if you have access to a lathe big enough to machine the center section face plate and is only a couple hundred bucks. Note to self - "Did I just say ONLY... . " It really helped my EGT problem. I used to be able to wrap the needle around the stop pin. Now I have to work very hard to get to 1350 although it can be done. And just think, you'd have a good primary for a set of twins.

 

[Jerred]

I can't believe this thread is still going!! Well, here's the update. I granaded my 35 at a dyno event at JandH Performance in Redding, CA (thanks to Joel for the loaner 35 to get me home, you guys are awesome!). So, I did what I should have done in the first place, call Pius Erbelle at Bell Turbo in Stockton, CA and begged him to build me a USB before he moves his shop. The result: 50 hp gain overnight, no other mods. I'm at 400 hp easy and loving it. The turbo really spools quick and hard, right to 45lb and the temps were only at 1400+ for the last two seconds of the dyno run. I'm going to pipe in a HT3B for a twin setup at 70lbs boost or so, after I stud the head of course. I got a custom plate from Piers (along with the cam and ringed head), so I have alot to do before May madness. I'll tell ya though, that USB is great all on it's own. I pulled my 10k # camper back from Piers' shop up and down the passes in WA, OR and CA and was able to do 70mph up all but two and never at more that 1200deg, which I'm more than comfortable with. A little surge if you try and shift while it's pumping out 20+ lbs of boost, but I just learned to back off the trottle ever so slightly before pushing the clutch, wallah, no surge. It's a beast, pricey, but a beast.