Running to much boost. How can I lower it????

[mbarryracing]

Doesn't the Turbo produce it's maximum efficient psi (in my case with a 2854r, 15psi) at all times?

RXrider,

Looks like he has a 2854? Even if it's a 2554 should be able to drop the boost to nothing.

Mike, did you take the 5 bolt outlet off the exhaust housing to make sure the wastegate is open (not just the arm) and there is no blockage in the port? who knows the previous owner might have welded the flap to the housing or something to get it to seal up...

 

[FLYBYU]

actuator or flap. start there

 

[FLYBYU]

I think he has it wide open now

If he had the flap all the open he would not have any boost

 

[mbarryracing]

Exactly, he has the lever WFO but that doesn't mean the wastegate flapper if flowing WFO (if at all). Doesn't make sense, I think ther culprit lies under the outlet cover...

 

[pdrmike]

Just had outlet cover off and everything is working fine on the wastegate. And yes, I did have wastgate tied wide open and still making 14 psi. This is turning into a head-scratcher!!

 

[aja636]

I just found out that the turbo you are having problems with is my old turbo I ran last year.

It is a 2854 off a CPR stage 1 kit. I put 300 miles on it last year. I had it set at 10 lbs on the waste gate and used a boost controller to get 16lbs on high boost. The sled was running with no problems when I removed it.

Nothing was done to it in terms of ported or welded or nothing. It was dead stock from CPR.

Just trying to add as much history and info on this to aid in diagnosis.

Check to see if your boost controller valve is installed right, make sure the arrow points to the actuator, make sure the hose isn't clogged,

Don't drill holes in the intercooler, bad Idea Vaccum issues boost leaking more headaches.

Just don't make sense!!!????

 

[FLYBYU]

i thought his boost controller is disconnected. there should be a solid hose going from the output of the turbo to the actuator. nothing in between it for now. maybe something collapsed inside the turbo blocking the port

 

[machz69]

i thought his boost controller is disconnected. there should be a solid hose going from the output of the turbo to the actuator. nothing in between it for now. maybe something collapsed inside the turbo blocking the port

Yeah I didn't think he had a controller on it. I would say then to take that selonoid right out of the loop. run the hose straight from the turbo to the actuator

 

[pdrmike]

What is involved in porting the wastgate? Can you just bore the wastegate hole closer to the size of the flapper and round things the best you can to make it try to flow better out?

 

[snowy1]

porting the waste gate isn,t going to fix the problem at hand, as the previous owner said it worked fine for him. something is wrong. there has got to be a restriction some where, if the waste gate is fully open and no restriction you would be making very little if any boost. can you disconnect the down pipe right after it comes out of the turbine housing and try it that way to see what happens. I know you took the muffler off but I would disconnect as close to the tubo as possible and see what happens.

 

[rxrider]

I'm just throwing out all I can think of.... here's another shot at it. With the Downpipe installed the flapper hits an obstacle in the DP not letting the flapper open much if any.

Run the engine on the jackstand with all panels and downpipe off so you can see and feel if the exhaust is exiting out the WG.

 

[Blue shadow]

There should be a 50 pilot jet to the turbo side and a highter jet to the on and off switch,nothing to the wastgate side Thats if you are using a manual switch from 7 psi to what ever you want

 

[kviper]

I talked to Mike on the phone today. He ported the wast gate and it dropped about two lb of boost. I wouldn't think porting the opening would hurt anything. It sounded like he was going to do some more hoping to drop one or two more lb. The way i see it is the resistance from the compressor side of the turbo is not creating enough resistance on the exhaust side to make the wast gate port the path of least resistance, So increasing the port size is giving the port less resistance and allowing more exhaust to flow easier. It sounds like every possible problem has been checked and rechecked so the question should be why is this turbo more efficient in making boost than all of the other stage one CPR turbo's? The previous owner had his base at ten lb but how consistent are gauge's, Maybe the gauge that is on there now is one or two lb high and the previous owners was one or two lb low. I don't know for sure but nothing else makes sense. kviper

 

[aja636]

Where is the boost gauge getting boost from?? Vaccum lines or the intercooler?

I ran a digital gauge off the intercooler which is probably a point or two higher then what is behind the throttle bodies, from I have been told anyway.

I ran this turbo set up with 3 different guages last year before I had one I liked, 2 out of the 3 read the same boost and the last one was only 1 point off. 2 read 10 psi and the other 1 read 11 psi at the port on the intercooler.

Porting the waste gate is a gain but with the standard down pipe from CPR there isn't a major gain in anything. The double down from powder lites will help with getting the exhaust out quicker and helping with efficiency and Lowering back pressure.

Does the exhaust have one of those S/S flex joints that could have collapsed?

Did one or both of the donut gaskets on the split pipe not seat right??

Try a differnt gauge for a run to see any fluctuation.

 

[kviper]

One gauge was in the cooler and the other was the boost controller which would have been reading from the line to the wast gate controller, I think he said he also hooked one between the throttle body and motor and still was at 14. He also at one point had the muffler off and the down pipe off and all is good. kviper