Here's what I found. When I checked the tube that my friend installed he only tack welded the pipe making a major leak. So I tig welded it and reinstall it. When I took it for a test drive the pyro was a slow clime and maxed out around 1200 but, that's without towing or hauling anything. My boost pressure is still at 20psi? Where are you guys getting your pressure readings from? I'm taking it from a plug on the side of the head near the intake heater. Should I be getting my reading from some where else? I also used copper tubing for the install.
As for any blockages or bad inter cooler, I pressurized the inter cooler before I put it in and I vacuumed out the head and before I put it back together and all the tubes I just made for the HE351 install.
I wish I could show pics, I went camping a few months ago and woke up to rain with my camera on the picnic table. The weather man said it was supposed to be a perfect weekend.

 

That's where I'm getting my boost reading from. Did you check to see if you wastgate is coming open as others have mentioned? When I put the 351 on my truck I tried to use spings and I ended up with only 20ish psi. So I got ticked and used a spot weld. Now it's got "enough"...LOL
I don't tow much but I couldn't melt this engine if I wanted to in the flatlands of AZ. Hope some of that helps. Good Luck

 

Yeah i'm guessin your wastegate is comin open a little. I did the same when i first installed my he351, I had a spring on the wastegate but it would still open and i couldn't get any boost. I put a turnbuckle on it and it fixed that and was then 40 lbs of boost. So maybe throw a small turnbuckle on it and tighten it up. I got mine for like $.89 at a hardware store.

 

I have that waste gate wire tired HUMMING tight, and it still pulls itself a little loose. When I tighten it more, it will yeild a few more PSI. It's amazing how much a slightly open wastegate will drop your spool. How are you holding it closed?

 

I checked that it is closed at an idle but I don't know when or if it opens. What is the stock pressure setting to open? I didn't want to completely close it in fear of blowing the head gasket. I have ARP studs but the head is not ringed. Do you guys think I will be OK keeping it closed?

 

Well I'm not going to tell you it's ok and you will never blow your head gasket, But I've seen my gauge at 48 with head bolts and a big port and polish on my head. BUT it's your truck and I understand your consern! Why don't you try the turn buckle Idea from Austin and see if that is in fact your problem, then go from there?

 

It shouldn't matter where you take ur pressure sample, anywhere between the compressor and valves, that is. Pressure will all raise at the same rate.

 

I re-tightened all the clamps, disconnected the hose to the waste gate and got the exhaust fitted to behind the cab. I just drove it into work and I reached a max boost of around 29psi and the pyro didn't go over 800*. I only live about 5 miles from work so it wasn't a real good test drive but, what a difference! THANK YOU GUYS for help! I have to do some adjusting to the pump now that I have enough air. Exhaust wasn't bad to fab up either, I used 2 new 90s and the 4" parts from my fathers truck that was almost new pipe. He bought a new turbo with 4" stainless all the way back so I got what was on the truck. Again, thanks for all your help!

 

Much better idea to take care of the pressure signal to the wastegate instead of wire or turnbuckle. A simple hose pinch and you have fully closed wastegate. Good you found better results.

 

What did you do with the sonenoid on the turbo. The he351cw has a solenoid the bleeds off boost unless powered up.

 

My truck stock made 24 lbs boost and after I installed the number 10 torque plate and change out the line to the turbo and added the new fitting I got with the 10 plate I make 34 lbs boost. I see pryo never over 900 towing my fiver and truck and fiver weight is 15656 lbs. I love my truck.

 

That will teach me for not reading closer..

I would either find a way to plug it or figure out the signal needed to keep it closed. Might only be a 5V solenoid or possibly 12V to fully close.

 

Well that might be a next step I will take, I didn't know that thanks. There is a guy on CompD that supposedly is selling a plug to get rid of it. I just took it for a drive and it maxed boost at 32psi and spools FAST. I'm very happy with what I saw tonight, I will have to look at that solenoid tomorrow. Thanks

 

two things...

It IS a 12v solenoid

You get 30ish psi with it off and 35ish with it on, it doesn't really bleed off boost, just controls when the waste gate opens, by altering what kind of pressure the waste gate sees by opening and closing rapidly on the trucks we get them off of.

Your probably better off just cutting that hose and plugging it somehow, and then drill/tap for a new boost reading for the waste gate. doesn't matter if u use take a sample from the turbo or from the manifold, its all the same pressure ;-)

 

I drilled and press fit the barbed fitting that came out for that solenoid in to where the compressor 90s. I thought that solenoid didn't let air past it till 12v were put to it, so I guess its another air leak. I bought one of those adjustable valves that manually adjust the air to the waste gate. I might try that once I plug up the solenoid hole. Right now I just have the hose plugged and nothing going to the waste gate . I am happy with the pyro temp readings and boost pressure I have though.