Engine/Transmission (1994 - 1998) Best HX35

[MMcCallie]

Who makes the best HX35? I'm looking for the fastest spool up, the most durability, and the lowest EGTs. If there is a better alternative, i'm also interested.



Here is some information on what my truck has as well as what i have planned for it. My second WH1C seems to be on its way out and i need a replacement, hopefully one that will last more than a few months. I have a lot of fuel, but am trying to plan compounds with an HT3B i already own. The first turbo was ruined by having it ported. The one on there now was sold to me by a shop that had it in their junk pile and told me not expect a year out of it. I've gotten 4 OK months out of it.



The truck weighs 9,600 lbs with one extra passenger. Modifications i have planned will someday put it well over 10,000 lbs. The engine compartment has less room than a Dodge so i may have to mount the big turbo above the exhaust manifold. I don't mind clearancing the hood and there is probably enough room as is.



When my original turo was ported, i had far less smoke on the bottom, higher EGTs, and could rarely get boost into the mid 20s. Before it was ported it made 42 psi, lots of smoke, high EGTs, and way more power. Having it ported did everything opposite what the guy guranteed, he never returned my phone calls.



When i put the current used turbo on, i had more smoke on the bottom and saw mid 30s for boost. Also got the best fuel economy so far, 15. 9 mpg. That lasted only a couple months. The neck snapping take off has reduced and now feels like i'm taking off in 2nd gear. There is very little smoke and often no boost showing while cruising. EGTs are also higher.



I don't understand how a turbo that is not working well will have less exhaust smoke, but that's what i was told by the shop where i bought the current turbo. I've found no boost leaks and it seems to be getting fuel. I figure that if i have to replace my turbo again, it is probably time to upgrade so that i can handle the amount of fuel i'm using.



From reading posts and talking to some who run compound turbos, it seems a single turbo could never give me the instant spool up i require for my constant stop and go city driving, and the big air needed for charging up mountain roads.



Piers told me their mathced compressor wheel and housing will spool quicker than a factory turbo and that it would be perfect with my HT3B. I wonder if, since i'll be running compounds, would i need to run a modified HX35, or just find a good used replacement? I've read posts about losing spool up with this setup and that is a huge concern.



I would like to stick with the 12cm turbine housing if that is the fastest spooling possible. If i decide to spend money on a turbo that spools as fast or faster than stock, which brands and models should i consider?

 

[12V Ford]

Either PDR, Dodgezilla, or HTT probably makes the best hx35. The PDR has a 58mm compressor wheel and the Dodgezilla and HTT (which are pretty much the same) have the 60mm wheel. The PDR should spools the fastest because it has a smaller wheel. I would either use a 14cmW or 12cmW turbine housing and have PDR enlarge the wastegate and put in a bigger flapper. They charge about $80 to do this IIRC. The 12cm will always spool the fastest, and I couldn't tell any difference between the PDR and stock turbo in spoolup. The only other size I would consider for pretty much stock spool up would be an HTBG, PDR super s300 or BD super s300 (all the same turbos). It has a 57mm comp wheel and 65mm turbine wheel. I would use the 12cmW housing for the fastest spoolup.



BTW, your HT3B should fit in the normal position without any bashing. The only thing you will have to do is redo your hx35 wastegate actuator bracket.



Not to change the subject either, but does anyone know what size of turbine wheel is on the HX35 and what the shaft size is compared to the HTBG?

 

[MMcCallie]

If the Piers turbo won't spool any faster, would it still be better to change to an HX35 or rebuild my WH1C? I've seen rebuild kits on ebay but have been told not to try rebuilding a turbo myself because it needs to be balanced. I've also read of people going hundreds of thousands of miles after doing their own rebuilds. Piers told me the HX35 is a better turbo, is it that much better that i should swap?

 

[12V Ford]

If the Piers turbo won't spool any faster, would it still be better to change to an HX35 or rebuild my WH1C? I've seen rebuild kits on ebay but have been told not to try rebuilding a turbo myself because it needs to be balanced. I've also read of people going hundreds of thousands of miles after doing their own rebuilds. Piers told me the HX35 is a better turbo, is it that much better that i should swap?

This I don't know, maybe someone else could comment on that. I would think that I would want my turbo balanced though.

 

[pwerwagn]

If spool is your absolute highest concern, you might look into an HY9 or nasty nine from an auto 24V truck. That would work good for a small set of twins if you use a large enough wastegate on the secondary, and spool quicker than a 35.



Clayton, IIRC the turbine wheel on the 35 is a 55mm. I'll have to check my notes as home to be sure though. Not sure on shaft size for the S300G, but I can get it.

See ya at the dyno saturday!!



--Jeff

 

[MMcCallie]

What would be involved in swapping to an HY9? Is it durable enough for a big, heavy, 4x4 truck? How much boost will it take stock? Would it hold up to a wastegated 50 psi with the HT3B? Is the HY9 wastegated or is there a larger external wastegate that i should use instead? Does the HY9 spool that much faster than the HX35 and will it be enough turbo to bring me down to around 1,200 from over 1,600 degrees in EGTs working with the big turbo?

 

[pwerwagn]

An hy9 should spool noticeably quicker than an HX, but flow less. It would probably be a decent match for a back yard set of twins with a 3B. I would only use the 9 if spool is your utmost concern. I dont know if you can mod the 9 WG to flow more or not, but I think an external is the best way to go anyways.



I dunno how much "boost" it will take, but you being in colorado should be more worried about PR than boost since boost at your altitude will put the shaft speed way higher than the same turbo at sea level.



It will handle abuse of a big heavy truck, it was a factory turbo on some 2nd gen 24V autos!!



It will run hotter as a single than a 35. It will spool quicker. It will flow less. It will make more psi than a 35 at the same power level, but thats irrelevant. You want air flow, efficiently, not high boost!!



--Jeff

 

[Forrest Nearing]

S300G (57mm compressor, . 70/12cm turbine)



wouldn't waste money upgrading an HX series

 

[pwerwagn]

Do you know the turbine wheel dia forrest? I for some reason recall the S300g being a 64mm turbine. . but that seems big for a 57 comp.



I was wrong clayton, HX35 is a 56mm turbine wheel, hx 40 is a 65.



--Jeff

 

[MMcCallie]

I plan to keep it under 50 psi for my stock head gaset and bolts. Guess i'll need to wastegate the HT3B as well to do that. So if an HY9 will spool that much faster, will it have less mid and upper range power than an HX35? I think i remember reading that the HT3B begins to spool around 10 psi so if i wastegate the HY9 at 20 psi or a little above, will there be enough air for a good midrange?

If i use an external wastegate for the HY9, i assume the wastegate on the turbo can blocked, yes? My power goal is 500 hp to the ground with safe EGTs and as little smoke as possible.

I really do like instant throttle response but won't go with an HY9 if it will be restrictive even with the HT3B. Oh, which turbine housing size should i use on the HT3B for either the HY9 or HX35? I'll look at the S300G but am trying to keep as low budget as possible. My current turbo needs replacing so i'm trying to plan it all at once.

 

[Forrest Nearing]

an S300G can be had new for under $800 if you know the right folks

 

[DLane]

an S300G can be had new for under $800 if you know the right folks

Send me your address then forest I will get you a check on the way

 

[Forrest Nearing]

I'm not the right folks, but I'll see what I can dig up if you'd like

 

[JHastings]

I would go with a 35 or a s300 if I were you. I don't think my 12cm w/ a 1" internal gate even flows enough with my setup and you have WAY more fuel than me. Spool is good with a good AFC setup. I am using a 23cm divided housing now on my 3B, but had a 26 before. I couldn't drive the 3B hard enough with the 26.

I want a 22cm, but heard they are hard to come by. I would also think that a HY 9cm would give you the problem that I am having with oil in my coldpipe. Look up that thread and read all about it. I may or may not be the only one with this problem, but it sucks.

With my setup peak egt's are about 1350*, but am thinking I have a bad injector. Also I get about 60 psi out of my setup. Although I love the twins, I'm not sure I would do them again. Just my input.

Jamie

 

[MMcCallie]

Thanks Jamie,
That helps. So are your injectors stock 180hp? Do your twins spool slower than the HX35 did by itself? Can you describe the difference you experienced by swapping to the 23 housing? Any differenc ein max ETGs?

1350 degrees sounds reasonable, about 300 lower than what i now have, but i guess i also have more fuel as you said. I think my HT3B is a 26 divided but i'm not sure. Do you guys think that would better match a stock HX35 with my other mods?

I can't afford an S300. If i were to spend that much , i'd wait and spend a little more for an excellent single. Still, i'm told a single will sacrifice spool or air and that compounds are the only way to get what i want.

I'm getting the impression that a stock HX35 will be my best option, and that i should probably use an external wastegate to keep it alive. I'm still making boost but have very little response on the bottom end, hardly any smoke, and extreme EGTs on the high end. Maybe i should just find a used HX35 that is still tight for now and wastegate it early to last unilt i can start fabricating.

 

[JHastings]

Injectors are 215's. Spoolup is just as good as a stock 35, maybe a bit slower, but not to noticeable. My peak egt's were 1850* to begin with. Thats why I think that I have a bad injector. 23 housing lowered an additional 50-100* over my 26 undivided. I would do a smaller 3B housing if possible if you are going to use a 12cm hx housing. 22 would be the best probably, but as I said they are hard to come by.

Do an external gate if you can. I would have, but I am just a college kid and don't have much $$.

Jamie

 

[Forrest Nearing]

you're seeing 1850* with twins?

 

[JHastings]

No that was with the single. Now I'm down to about 1350* with the twins. I still want lower. I have a couple leads on k31's. I assume I would need to make a new hotpipe and coldpipes?

Forrest, what kind of temps did you see with your twins. I know you had an external gate. Did you ever have the problem of sucking oil past the compressor seal?

 

[Forrest Nearing]

actually, that setup was shelved... only setup I've run was a PDR35-12 on top w/ an S400 on bottom. I wasn't very pleased with the spool up empty. Good towing setup, but I run empty-ish most of the time.



the setup I want to build is a 62/65-14 or a 62/71-12 or 14 on top w/ a 71mm K31 on top. w/ port work and larger wastegate flappers on both exhaust housings

 

[MMcCallie]

I don't have time to build compounds right now. Is there a single HX35 setup that will survive heavy towing and lots of fuel? I would want to use a 12cm housing if possible, since i think that's what i'll want when i add the HT3B. A stock turbo won't survive with 400 hp, even wastegated to 35 psi, will it?

I'll be towing about 14,000 lbs of trailer and my truck will weigh at least 10k. I'm looking for a super tough, fast spooling, high flowing compressor wheel and housing. Will the 12 cm turbine housing from my WH1C mount to an HX35 compressor side? I'm thinking no because my WH1C has a v-band clamp and the HX35 clamps together differently, is that right? I've got to do something within the next couple weeks, have to move by the end of the month.