t3 dont spool till 4000 rpm!!! wtf

[farmerz24]

ok so i finally got to take the car out t3 .82 ar stage 3 60-1 compressor. no boost till 4000 rpm i dont understand.. the front collector is leaking a small amount and the wastegate is not sealing 100% (ps anyone know where i can get a new hks 50mm wastegate plate and gasket ) but i tink it should spool well before then... i would say it is a exhaust leak causing it not to spool until then but its not that big so its hard to say.. but when it does come on it does hit hard, even for 6 psi..

so any ideas? i am just running a downpipe so once i get my exhaust done ill be able to hear more exhaust leaks but i thought it woudl come on much earlier than 4000 rpm.

any advice?

thanks guys. ill get some pics and a video soon.

[RedZMonte]

Hmm. with just a downpipe and no exhaust it should actually spool faster then with the exhaust hooked up. depending on how big of a leak you are having that definatly could effect the spool. how big of a downpipe and x-over are you running? that is a pretty large A/R that probibly also has a effect on your spool. My t-04e spools about the same. Your turbo being a T3 w/ a larger Ar sounds to be comparible as for the spool up.

S

[Joseph Upson]

You have 3 things working against you achieving low end boost levels, a large turbine housing if this is on a 3400 intended for low boost levels ~7psi and even more so if the engine is smaller, a suspected exhaust leak and a wastegate that is not sealing 100%, you are lucky with those three situations you are building any boost at all. Simply adjusting the internal actuated style wastegates so that they are partially open without boost bumps the rpm up at which you would start to build boost so two leaks with a turbine housing that's on the large side is going to make a big difference. Turbine housing alone is fine, but you would be amazed at how big a difference a small leak can make to your spool up time and rpm.

[TurboGTU]

THat thing should spool up hard at about 2500-3K rpm. Even with a bottle neck Ford 2.3L, that turbo spools up at about the same RPM (3.5-4Krpm).

Those leaks are a big problem. ALso make sure your wastegate actuator is not leaking, check to see if its sitting down compleately, check intake hoses for good conection/torn sections. Make sure you don't have a leaky BOV if so equiped. A too small IC will also cause a problem in achiving spool up.

[Kohburn]

i'd say between the leaks, the larger exhaust A/R, and the 60-1 turbine i'm not too suprised.. properly working it should come on at about 3000

i haven't played much with the exhaust A/R yet - but right now i've running a .65 exhaust housing

[timg]

Fix the leaks and all of your problems first.

A 0.82 a/r stage 3 T3 turbine is NOT that large. The A/R is a bit big, but you've got to remember that a stage 3 wheel is pretty small and T3 size turbine housings are fairly small. What size is your motor?

The 60-1 compressor is quite large. It will definitely slow down the quick response that the T3 turbine would have with a smaller turbo.

Anything 3+ liters should have full boost by 3500 rpm with this setup, if not 3000 rpm.

Tim

[farmerz24]

thanks for all the advice. i pressure tested the charge piping there were small leaks on one vac line port, so i fixed that and we will see how it goes from there. still have to fix my front collector leak and wastegate leak, so we will see how it goes.