Engine/Transmission (1994 - 1998) Boost Elbow ?

[pete97]

I got a #10 plate last fall. Not from TST. The boost elbow came with it but it is not like the elbow from TST. There is no set screw. The elbow is just restricted by a small hole at the one end. Should I get the one from TST? My boost goes up quicker and higher than with the stock one but never goes over 20 PSI. What do you guys think? Pete

 

[CToney]

Your boost should go higher than 20psi with a #10. I have mine slid back and still see 20psi easily. I would think you have an air leak somewhere. When the set screw came out of my boost elbow I would only see 15 psi ( riding on AFC arm) With the stock fitting I can see over 30psi. You might have an air leak preventing the afc from moving to allow the gov to ride the plate. Did you slide the afc forward? Does she smoke black?

 

[pete97]

Where might the air leak be. She will smoke black if I don't have much boost built and I get into the pedal I can bellow out the smoke. I'm pretty sure I haven't had it ove 20-25 PSI. Should I get the elbow with the set screw? Anyone on the Pittsburgh Pa area that wants to help me fine tune my truck? Thanks Pete Also the plate is in the stock postition and I made sure that the governor was hitting it correctly.

 

[CToney]

You might have a leak going to your boost guage then. I don't smoke at all but I've adjusted my afc to do that. I would check or replace the line. You could disconnect that guage and plumb one so it runs up onto the cowl (duct tape it on) and see if there is a difference. You should be hitting over 35 psi for sure. With my plate slid back just a little I saw over 35.

 

[pete97]

CToney, do you have a boost elbow that is from TST or someone else. I don't have one that has the adjustment screw. I have one coming and I will put this one in and try that and see if the boost goes up. Thanks Pete

 

[vssman]

It's not too hard to make your own. You need to get the elbow at the harware store (1/8 NPT I think) and then drill down through one end of it using the wall as a guide to tap and install a set screw (1/8 thread - again I think). A little removeable lock-tite holds the screw in place. Screw it in untill it bottoms out and unscrew it about 1 turn to start. Go for a ride and adjust from there. A stock HX35 is good to around 35PSI then it'll increase EGTs if you go way above that. I have my hybrid set to 42psi.

 

[PKemp]

Or, you could simply take a 1/4in pipe plug and remove the elbow completely, put the plug in its place and plug off the waste gate line. Put one of those little rubber tubing caps over the metal wstegate line just to keep the dirt out. Turn it into a non-wastegated turbo.

 

[pete97]

If you plug the wastegate, what does that do for you? I know some about diesels, but I am still learning. Pete

 

[vssman]

Just my humble opinion...



I would not plug the wastegate. You really don't want the pressure to go over 35 or so PSI on a stock HX35 for 2 good reasons:



1) You'll be heating the air causing the EGTs to increase.

2) You'll be shortening the life of the turbo.



I know I find things break only when I don't have any extra cash to pay for the repair and only when it's dark, cold, raining... with no cell phone reception.



Edit: ... Non-wastegated turbos run larger exhaust housings to keep pressures in check

 

[CToney]

Pete I bought my plate and elbow from pdr. I could see the same peak boost with the elbow in or with the stock fitting in. The set screw came out (lock tite didn't lock) and I don't plan on putting the elbow back in. My egts a low hard to get over 1100 so I don't need it and I want my boost under 30 psi or so to preserve headgasket. I guess no more than 250hp 650tq for me. Hopefully everything can live at that level.

 

[pete97]

How hard do you have to get on it to see 30-35 lbs of boost? I have seen mine at 20 or so under some throttle but not wide open. Thanks Pete

 

[tp0d]

I have my w/g plugged. I regulate my boost with my foot. Just gotta watch the first few days of driving it like that, then you get the feel of it. 32-33psi is all you want, no more.

Depends on how far forward you slid the #10 as to how much boost you`ll get. I set mine 1/16" forward from stock, but then again I ground mine to a #100 setting. The stick might also have an effect on max boost, I dunno.

Give it a try, just dont cut the hose short/etc so if you want to hook it back up, you can. Its tempting, but definetly dont go over 35psi, the turbo and headgasket are at risk. . Have you done any timing yet?

good luck

-j

 

[pete97]

TpOd, no on the timing. Do you know how to do it or do you have the tools? Also, my #10 is in the stock position. The AFC is full forward I think. Never touched the star wheel. Pete

 

[CToney]

To see 33 psi I have to be 2450rpm+ With a load on going uphill its easier to get higher boost. 15psi till 1700 then 20+ at 1900 25psi 2200 rpm

 

[pete97]

Ok, that is close to mine.