Only Low boost

[ChevelleDude71]

I have my truck all together but I'm only getting 8-10 PSI of boost. I adjusted the wastegate this morning and I'm still only getting 10 PSI. Last night I even tried a manual boost controller and turned it all the way up but only got 10 PSI. It's frustrating cause I know the ultimate chip and the factory boost solenoid are suppose to give me 15, (T1-15) I just don't know what the deal is.... The boost is steady, and not fluttering so I don't think i have a boost leak, but I wont rule that out just yet...I'm starting to think my truck is taking my "Lo Boost" license plate a little too seriously.

 

[Syclone#2960]

Re: Only Low boost

you are probably losing boost through one of the ATA elbows. Check to see if there have a small hole in them.

 

[ghettosled]

Re: Only Low boost

stock wastegate selenoid? try pulling the vacuum line completely off the wastegate actuator. if still no boost, look for leak in charge piping or plugged exhaust.

 

[Don W.]

Re: Only Low boost

Sean,

Restriction in the intake somewhere? Unlikely, but worth checking.

Does boost build fast and then hold at 10# or do you really have to get on it for boost to build?

Off the wall: Check that the turbine spins free.

 

[Flyin Ryan]

Re: Only Low boost

clogged cat? unbolt at the dp and drive it and see if you get more boost or if you have a cutout open it and see how she runs

 

[ChevelleDude71]

Re: Only Low boost

I unplugged the boost solinoid and got 6 psi. I passed smog last week so I think the Cat is still together. I need to check the intercooler piping again, but I'm sure if I had leaks that the boost would spike then bleed off. . . . but I'm not ruling that out yet.

Hey Mike on this turbo you shorten the wastegate rod to "increase" boost and lengthen the rod to "lower" the boost. Right?

 

[ChevelleDude71]

Re: Only Low boost

Sean,

Restriction in the intake somewhere? Unlikely, but worth checking.

Does boost build fast and then hold at 10# or do you really have to get on it for boost to build?

Off the wall: Check that the turbine spins free.

Don't know about a restriction, but the truck builds boost pretty quick, I'm not sure how fast it is supposed to be but feels quick to me. i do love that I slowly walked away from that 97, LT1 camaro with my truck only producing 6lbs of boost and at 3/4 throttle. I can't wait to get 15PSI and be able to drop the pedal to the ground.

 

[Don W.]

Re: Only Low boost

Actually this is proly good for breaking in the motor!! LOL let us know what you find.

 

[SpoolingTurbo6]

Re: Only Low boost

Can you put the stock chip back in? Might be the lo-fuel boost limit ? Worth a try

 

[ChevelleDude71]

Re: Only Low boost

Can you put the stock chip back in? Might be the lo-fuel boost limit ? Worth a try

I just cut out the cat and placed a 3" pipe in place of it. now I get 10 PSI. This is with the stock chip and stock fuel pressure, RPM stage one turbo......any other thoughts?

 

[syclone0209]

Re: Only Low boost

what air filter setup are you running

 

[Don W.]

Re: Only Low boost

what air filter setup are you running

My idea about 8 posts back. Still a good idea to check intake restriction. Thing is, if I remember correctly, since I talked to Sean, it runs up to 10psi or whatever rather quickly and then just stops there. My gut tells me it's something in the wastegate. Not closing correctly, I dunno, but something just stops his boost at 10-12 psi and it stays there.

Sean, Have you tried pulling everything off the front of the turbo just as a test?

 

[ChevelleDude71]

Re: Only Low boost

My idea about 8 posts back. Still a good idea to check intake restriction. Thing is, if I remember correctly, since I talked to Sean, it runs up to 10psi or whatever rather quickly and then just stops there. My gut tells me it's something in the wastegate. Not closing correctly, I dunno, but something just stops his boost at 10-12 psi and it stays there.

Sean, Have you tried pulling everything off the front of the turbo just as a test?

Do you mean just the cobra elbow and the filter I have on the end? I just dropped the intercooler and I see no restriction there. I'll put it back together and pull off my air filter and see how it does...

 

[4C FED]

Re: Only Low boost

What are you using for a boost controller?
Do you have a blow off valve?

 

[ChevelleDude71]

Re: Only Low boost

What are you using for a boost controller?
Do you have a blow off valve?

I'm using the stock boost solinoid ( brand new ), with the wastegate that came with the RPM Stage one turbo. I do have a vortech BOV and the valve is adjusted pretty tight, but could go tighter.....

 

[4C FED]

Re: Only Low boost

I'm using the stock boost solinoid ( brand new ), with the wastegate that came with the RPM Stage one turbo. I do have a vortech BOV and the valve is adjusted pretty tight, but could go tighter.....

So you've checked with Datamaster, etc. to make sure it's not a KR issue?
Do you know what pressure spring is in the wastegate actuator?

 

[ChevelleDude71]

Re: Only Low boost

So you've checked with Datamaster, etc. to make sure it's not a KR issue?
Do you know what pressure spring is in the wastegate actuator?

ya I have ran it on my laptop and I'm getting 0KR no matter how hot the day is or how hard I smash the gas. (stock chip, 11 PSI max with 100OCT in the tank)

I think mike at RPM said the spring should be 8 PSI but don't quote me on this. I'm not sure really.

 

[4C FED]

Re: Only Low boost

So it sounds like you're only getting base boost.

You could remove the pressure feed to the solenoid from the turbo & cap the nipple. This will remove all boost control so you will need to be VERY CAREFUL that you don't overboost it. You should see more than 10 psi. If you do I would start looking at the boost control system.

If you don't see more than 10 psi, I would start looking for a leak.

 

[Don W.]

Re: Only Low boost

I think mike at RPM said the spring should be 8 PSI but don't quote me on this. I'm not sure really.

This could explain allot. Wire the WG shut and CAREFULLY go for a drive and see what happens. Bring wire cutter along to do the disconnect, if you have to, along the way. :roll: