Old School HX35/HT3B vs Modern Compound Setup

[estrada5.9]

Good read thanks.

[pic_jon]

I like where this is going

This is going to be one of those threads where we copy/paste its link in other threads and say, "Here, this thread has a ton of information. Read it.. do it.. then give thanks."

Can't wait for more updates

[Bersaglieri]

Thanks for the encouragement guys.

Current update: I'll be adding some kind of write up on the DTT belt driven fuel pump in the near future. I've gone through, measured, and removed nearly all restrictions in building this fuel system. No 90* turns, no small orifice fittings, no big neck downs. Just ordered the last of the parts today and hope to have them in for next week.

I'd have more time to work on this truck if my G/F didn't drive a Ford

-Dustin-

[Bigdawg6969]

I cant believe that your getting that hot with a set of twins I constantly pull a 48ft Enclosed Triple axle race trailer that weighs 10k with another 8k in the box and under full pull coming up the Rockies highest I ever hit egts wise was 1225 and that is with a 62/71/13 HTT.

[Bigdawg6969]

My guess is gates are way out of wack

[2wpuller]

Good thread. I'm running a hx35 12cm drilled out wastegate and a Ht60 23cm my egt towing witha gross wt. of 26.000.the highest I have seen on egt is 1150 at 45psi to 50psi.330hp inj.timming 16deg.O this is all on my Perkins 6.0

Dale

[SuperDave4x4]

Bump...

Was doing some research on HX35 twins, but now I'm curious as to how your fuel issue turned out.

Also how are the twins working for you now?

[Bersaglieri]

Originally Posted by Got Smoke?

I take it still no towing results?

Update:

Towed again a few days ago. Unfortunately, no big change in EGT. Not sure if I mentioned it earlier, but I've got some nasty governor spring bounce when I tow. When I'm empty, no bounce, but towing something on the gooseneck it'll bounce. Typically starts when the converter locks in 3rd with low to moderate throttle. Starts barely noticeable and if you don't get into the throttle hard, it will surge/bounce worse until you feel like the truck's going to bust something. I'm going to mess with the governor springs tomorrow to see if I can fix the bounce. Actually spoke with Garmon about it last week trying to track it down.

However with the higher fuel pressure [tighter OFV] the truck's got more low end, and EGT's don't shoot up as fast.

Fuel: I've got the DTT Assassin pump, drawstaw, 1/2 line, special pump M16 oring to 1/2 NPT fitting, and filter head setup. Just waiting for a decent weekend to install.

As far as the gates being off, the HX35 doesn't open all the way until 38psi. From what I hear I should have it open at 18-20psi. Fortunately all 6 cylinders are gated. I'd like it to open sooner but the only way I think of getting it to opening sooner would be shimming the linkage or something, but then you run the risk of having it hang open. How are you guys getting them to open sooner? Later is easy, just restrict the pressure input into the diaphragm. I'm open to ideas.

-Dustin-

[f6jbob]

I bet you a dollar to a doughnut if you clamp your rear springs or put some traction bars on your truck your gov. spring problems will disappear.

[Tate]

Originally Posted by f6jbob

I bet you a dollar to a doughnut if you clamp your rear springs or put some traction bars on your truck your gov. spring problems will disappear.

Why would spring wrap become an issue at constant speed or light acceleration, but not heavy accel, when spring wrap normally occurs? I've had this for the last year, first came on after I installed SDX Comp DV's, then moved to only when I was towing something when I went back to the stock 181's, but upgraded from 3k's to 4k's. 4k's and the Comp DV's was just a nasty combo to drive.

[f6jbob]

Originally Posted by Tate

Why would spring wrap become an issue at constant speed or light acceleration, but not heavy accel, when spring wrap normally occurs? I've had this for the last year, first came on after I installed SDX Comp DV's, then moved to only when I was towing something when I went back to the stock 181's, but upgraded from 3k's to 4k's. 4k's and the Comp DV's was just a nasty combo to drive.

I wish I could splain it to you and show you how smart I am but I got nothing. All I do know is that bars or possibly clamping the springs will probably take care of the problem. I had the same issues with 2 different trucks and put bars on. No more issues. I haven't tried clamps on the springs because I had bars lying around. Clamps would be easy to try.

[Bersaglieri]

Not sure if it helps to know, but I've got the 3500 over load springs and Firestone airbags out back. The bags were aired up when this happened.

-Dustin-

[WUnderwood]

air them down and see what happens

[2wpuller]

It could even be Posi clutch's going out.That is what my sons truck did.some times you might getaway with changeing the fluid and putting new posi aditive.

Dale

[f6jbob]

Originally Posted by Bersaglieri

Not sure if it helps to know, but I've got the 3500 over load springs and Firestone airbags out back. The bags were aired up when this happened.

-Dustin-

I had bags on my trucks also. Once you put some bars on it the truck handles much better empty or towing. It doesn't need to be anything fancy or overkill. Just something to limit movement on the rear end.

Jim

[Bersaglieri]

I'm going to address one issue at a time and work from there. I'd like to start with the wastegate since opening up at static 38psi seems way off. I saw big blue24 wrote this a while back:

Originally Posted by Big Blue24

I already mentioned this in your dyno thread, but it needs to be repeated.

When you enlarged the stock HX35 wastegate to 30mm+, the little actuator no longer has a strong enough spring to hold it closed. Drive pressure combined with boost working internally on the actuator lets the gate crack open at 10-15 psi. When that large wastegate cracks open, it diverts too much drive pressure from the HX35 and airflow suffers.

Obviously, low airflow hurt your dyno numbers, and it apparently hurt your towing performance as EGT's soared on your last heavy towing adventure.

If you're a machinist, build an adjustable spring controller for the HX35 wastegate using a heavy spring and a threaded rod for easy adjustment.

Your best temporary fix would be to pinch the wastegate line shut with a pair of vice grips so that boost does not help open the wastegate. It will still open early because the wastegate is too large and drive pressure will easily overcome the spring tension in the wastegate actuator, but, it will be better than it is right now.

Cutting back top-end fueling with a fuel plate will also help with EGT's. This will also severely limit horsepower. If you fix the wastegate problem, you'll gain horsepower and have better EGT control.

I think I'm going to tow with the wastegate line plugged just to take note of the changes. I'm also going to drive empty to work tonight pinched and see what happens.

I'm also looking for a replacement wastegate, thinking there maybe a problems with mine. I currently have this stock style:

Dodge Cummins 5.9L Holset HX35 Turbocharger Wastegate Actuator HX-35 turbo | eBay

I was BSing with a few buddies and we were wondering if anyone has rigged up something utilizing the internal flapper except drive pressure actuated instead of boost. Or perhaps the pictures of the spring style that big blue24 mentioned?

I'm planning on doing some towing runs with the airbags empty as well this week.

Bare with me I'm on midnights.

-Dustin-

[Trimmy1]

any updates? very interesting and informative thread.

[gwhammy]

Do away with the wastegate actuator and put a spring wastegate on it. Easily set by taking the cold air pipe off and just run it on the little turbo till set. I've set mine from 18 to 36. Total control of boost at around 26 to 28 seems to be where mine works best. Spring gates are really easy to build and adjust.

Pm me a phone number and I'll send a couple of pictures of mine to you. Been using it over two years now with no problems.

[Bersaglieri]

Update:

Well I spent what little truck time I did have last week fixing my melting head light switch, however today I should get around to taking a few clicks out of the governor springs and report back.

Last week I did pinch the waste gate, with little or no change other than spinning the HX35 harder. [Higher cruising PSI, higher cruising EGT, higher overall boost] Bounce is still there. I actually tried to induce the bounce empty the other day and I can, barely, but I can.

Airbags don't seem to effect it either.

I found these: Stainless Diesel Spring Wastegate

Not sure if stainless diesel is the maker of them or just a middle man, but after seeing the picture it seems the drive pressure in the exhaust housing of the HX35 pushes against the waste gate flapper and the spring pushes back against it. Basically adjusting the spring load decides how much drive pressure it required to open the waste gate.

Pretty cool and something I never thought of. Of course in the spirit of being a cheap ass, I'm going to try and make one of these vs buy one. It would also address the flapper issue big blue24 talks about above.



-Dustin-

[SuperDave4x4]

Post some pics when you get it installed! I'm thinking of using my old HX35 in a set of twins, but just can't decide how efficient it would be. My truck is a fulltime DD and I tow light stuff.