greco96

Ok here's the deal. I have a t3 turbo .63 it made 5psi after then first run. Now I can not get it to boost at all. I know the gauge is ok because I have a megasquirt connected and the MAP is also stating no boost(2psi). I have checked the wastegate and BOV both seem to be working fine. ( disconnected each and still nothing). There is no leak on the intake tubes ( short tube straight to manifold). there is a small leak on the exhaust manifold( plan to fix) also the oil to the turbo does not seem to drain through.
question:could the exhaust leak cause that much drop( goes from vacuum to 1psi)
:could the oiling problem cause the drop and how to you clean it out it passage does not seem to go straight through. should I take it completely apart the clean out.
any help would be good because im stuck with no boost.

sleepy 7 bolt

An exhaust leak is not the same as a boost leak. Is the turbo locked up by chance? Also just because you look at the intake pipe and couplers does not mean they are not leaking. You need to do a real boost leak test by adding pressure to the pipes and listening and or squirting water to actually find a leak.

Is this an ebay turbo and wastegate?

The fact you think the oil is not running through the turbo may indicate you may have siezed it.

greco96

thanks for the infor. Sorry its been a while from the last update. I found the problem. first was the garrett turbo which i rebuild and cleaned the passage so that works( still changed for a bigger turbo) second was that the precat was what caused all the problems. Once i removed it there was not problem and i could boost to 15psi. Now im back to the same problem this time its different. Before at the 15psi i had 3bad pistons( ring lands were broken). they have been replaced so now i need even more flow from the exhaust. I will have to increase the tubes to 3inch down and get a new cat for the flow. I can boost to 10psi but i do think thats the problem( still need to check the manual controler)

brettsb16a2

15 psi is too much on stock pistons., 9-10 max with an excellent tune only.

greco96

but if i keep a eye on the temps of the exhaust i should be able to just not for long times. I have run the engine at 15psi with no sign of wear on the piston but the fuel map is rich and i keep a close eye on the intake temps( megasquirt uses the temp not map)

brettsb16a2

To even be safe you have to run so rich you aren't gaining much horsepower. If you have forged pistons then do what you want, i am just talking about stock pistons. 15 is high on stock, you will blow it up again. What is your 1/4 mile time at 15 psi?

greco96

i have not had a chance to get to the track and see what times i will get. I have ran it hard for 1/4 mile distance thought. i needed it to help with the tune and data log what was happening. i have talked with others that have pushed this motor harder 400+ on the stock ones . I am only trying to to get around 300or 250 at the wheels. from what I have read heat is the many killer. Most times that is because of the rise in intake temp and pinging both of which i have not had. I run at 13-12.5 afr currently on hard boost and 13-14 on little to none. intake temps around 70-100.

greco96

my big problem with the pistons was before the turbo. I ran cross country NY to TX with overheating, and oil leaking problems so i think that is what really did it in. One point before i found the leak i was dumping oil in the engine(1qt every 15 mins just to make it to a spot i could fix it)

brettsb16a2

I never tune past 12.3 in boost and i max out between 10-11 psi. Currently i am slowly tearing down the engine to put some forged pistons.

What is this x country drive from NY to Tx? Is it like a race or a drive.... gumball?

greco96

no it was not a race. i just drove there and back to work with a company