Hx back to Hy?

[rseabur]

Put an hx on a couple of weeks ago and not impressed with it campared to the hy. Am I missing something? I had a turnbuckle on the hy and have the edge boost elbow on the hx. The Hx seems to be a lot slower boosting up, running hotter and taking a lot longer to get down to 350 for shutdown. All of this while driving empty. Will it perform better under load? I am concerned for when I put the 13000 lb fifth wheel behind it. While cruising at 60 empty I am at 5lb boost and running around 750-800 with the juice on 3x5. Seems hot to me. The hy was around 7lb boost and 700 if I remember correctly. I am not see the advantages. I am wanting to get some rv's or some +50 injectors also. What are your thoughts?

[Mopar1973Man]

I'm running HX35W Turbo with no issues with +50HP injectors and Edge Comp on 5x3. Normal empty cruising 55-60 MPH is about 2-3 PSI and 550-600*F. Towing at 55-60 MPH with 8,000 pound trailer it floats around 750-900*F no issues. Climbing 6-7% grade I can pull it right at 53-55 MPH and float between 1,000-1,100*F but that being smart and dropping from 5th into 4th gear.

 

I would say turn the Juice up more but I know you got a Automatic.

[rseabur]

So I could turn the juice up while driving empty and that would help until I got some injector? Then once injector are installed I could turn it down a bit and the injectors would compensate. I thought that either juice turned up or bigger injecters would make it run hotter. Is that not the case?

[rseabur]

Moparman do you tow with comp on 5x3?

[mulcher812]

I run my HX on 2x5 with my smarty on 6 and towing a 28.5 tailer at 12000lb mine will get up to 1100 but that's it on 6% grade.

[War Eagle]

I don't know a lot about the HY35 but I am thinking it has a 9cm2 exhaust housing where as the HX35 on my truck had a 12cm2 opening.  So if the HY35 and the HX35 flowed the same amount of air (and I don't know if they do or not) then you could definitely feel a bit of lag because the velocity of the exhaust gas spinning the turbo would slow down some on a bigger exhaust housing.  Thus the spool up would be slower. 

 

This might be the issue you are noticing on the slower boost. So I would first verify what you have for a housing on the HX35 compared to the HY35.  You can even get a HX35 witha 14cm2 exhaust which would even creat more lag in the spool up when compared to a 9cm2 housing..

 

I run and HX35/40 hybrid with a Quadzilla ZXT+ (which is a 65HP chip) on 14cm2 housing and I had a little bit of lag on the spool up because of the change from the stock HX35 with 12cm2 housing to the larger 14cm2.  But when I installed my RV275 sticks on my 2000 with auto and positrac rearend it made all the difference in the world.  With more fuel I can lit the turbo early and I can easily spin the tires from a dead stop non boosted launch.  I could never do that with the stock HX35 and Quad ZXT+.   My top end has also much improved.  When I kick it down for passing it gets your attention.

 

Of course you might have other issues working against you but if your overall performance is worse with the HX35 then I would suggest the first place you start to check out is the exhaust housing sizes.  

[Mopar1973Man]

Moparman do you tow with comp on 5x3?

Yes. I've towed even on 5x5. What's really wild is towing up a 6-7% grade set the cruise and then turn the Edge Comp off from 5x5 and watch the pyrometer. It doesn't change. Because the truck has to fuel X amount to pull Y amount of weight up a 6-7% grade so regardless of settings it shouldn't change much from Edge Comp to OFF.

 

With the Edge Comp on 5x3 and towing the RV I've had the rear tires break loose on paint lines on the highway, smooth spot of asphalt, or a bridge seam.

[rseabur]

I don't know a lot about the HY35 but I am thinking it has a 9cm2 exhaust housing where as the HX35 on my truck had a 12cm2 opening. So if the HY35 and the HX35 flowed the same amount of air (and I don't know if they do or not) then you could definitely feel a bit of lag because the velocity of the exhaust gas spinning the turbo would slow down some on a bigger exhaust housing. Thus the spool up would be slower.

This might be the issue you are noticing on the slower boost. So I would first verify what you have for a housing on the HX35 compared to the HY35. You can even get a HX35 witha 14cm2 exhaust which would even creat more lag in the spool up when compared to a 9cm2 housing..

I run and HX35/40 hybrid with a Quadzilla ZXT+ (which is a 65HP chip) on 14cm2 housing and I had a little bit of lag on the spool up because of the change from the stock HX35 with 12cm2 housing to the larger 14cm2. But when I installed my RV275 sticks on my 2000 with auto and positrac rearend it made all the difference in the world. With more fuel I can lit the turbo early and I can easily spin the tires from a dead stop non boosted launch. I could never do that with the stock HX35 and Quad ZXT+. My top end has also much improved. When I kick it down for passing it gets your attention.

Of course you might have other issues working against you but if your overall performance is worse with the HX35 then I would suggest the first place you start to check out is the exhaust housing sizes.[/quote.

I found these 2 numbers.......3592766 and 3530521. The first is the assembly # and the second is the # cast on to the exhaust housing. I tried looking up but came up with nothing. The turbo came off of a 02 manual. I believe it is a 14cm but not 100%. Maybe someone can give me some info on those numbers.

Edited April 13, 2014 by rseabur

[CTcummins24V]

If it's stock it's definitely the 12cm. The number is stamped inside the turbine housing, just inside the flange so you'd have to take to the turbo off to see, or unbolt it at the turbo to manifold connection and try to peek in.

 

I did the HY to HX swap and there wasn't a huge difference but it spooled slightly slower and gave a little more top end, just like you said. I wouldn't switch back especially if you're towing or pushing it, not to mention you have the edge JWA. And, if you do injectors the HY will get toasty warm. I have switched my 12cm turbine housing to a 14cm and I actually think it spools faster, but it's non-gated and I have +60 HP injectors. Injectors are fun and functional, I would do them! 

[volkswagon]

I'm really clued out about all this turbo stuff so please help me here. Does this 14 cm housing take the same exhaust elbow as my 12 housing would? I have an exhaust brake but I'd like to flow a little more air to help my towing egt's too.

[mulcher812]

rseabur - if you take the turbo off and look inside the exhaust housing on the engine side where it mounts to the exhaust manifold there are #'s  on the inside of it. This will tell you if its the same as your HY turbine housing. If it is what are the #'s of both housings?

 

volkswagon - the HX/HY turbo series use the same housings just different sizes 12cm - 14cm - 16cm this is the half the size of the discharge turbine. they all have the same bolt pattern on the back side and they can all be interchanged.

[volkswagon]

rseabur - if you take the turbo off and look inside the exhaust housing on the engine side where it mounts to the exhaust manifold there are #'s on the inside of it. This will tell you if its the same as your HY turbine housing. If it is what are the #'s of both housings?

volkswagon - the HX/HY turbo series use the same housings just different sizes 12cm - 14cm - 16cm this is the half the size of the discharge turbine. they all have the same bolt pattern on the back side and they can all be interchanged.

Thanks! So if I indeed do have the 12 cm housing would going up to the 16 give me noticeable improvements do you think?

[mulcher812]

You don't want to get that big with out doing some sort of twins. The reason is your exhaust drives your boost pressure. So if you have a 16cm exhaust housing then there is no boost pressure. A lot of guys do a drive pressure reading and figure out what it is with the stock setup and do the math from there to get the right boost pressure to exhaust pressure. The most ideal is a 1:1 rotio.

[rseabur]

Spoke with Eric @ Vulcan performance. He has a set of 60-70 Hp injectors. Do you guys think they would be too big or smokey for my setup? He said he uses all bosch components. Not sure about diesel auto powers 60 Hp injectors. They don't look the same. Look stainless to me. I am open to suggestions on good quality injectors for a good price. I only want to change them once.

Edited April 19, 2014 by rseabur

[hex0rz]

Well, I've got the 75 sticks from DAP and have not had a single problem. They were the cheapest to go with, at the time.

[mulcher812]

Spoke with Eric @ Vulcan performance. He has a set of 60-70 Hp injectors. Do you guys think they would be too big or smokey for my setup? He said he uses all bosch components. Not sure about diesel auto powers 60 Hp injectors. They don't look the same. Look stainless to me. I am open to suggestions on good quality injectors for a good price. I only want to change them once.

I know the DAP injectors are all bosch injectors and they are all flow matched. If i known about DAP when i bought mine they would be DAP injectors.

[dripley]

DAP uses bosch products also. I have seen the picture where they look very shiny, not sure that is how they come. Give them a call and put your mind at ease. I have purchased from both and they are very reputable and will give you a good product. 

[mulcher812]

Rseabur are you still running the HX or did you go back to the HY? With the new sticks it might be the difference you were looking for

[rseabur]

Still running the hx. Pretty happy with my setup for now.

[joecool911]

Mulcher812 helped me do the swap to HX with RV275 sticks. Good combo on my truck. Turbo whistle is louder. Tows better than with the HY.