t3/t4 slow spool...

[sunnys14]

i have a t04e turbo .50 turbine, .63 compressor. i am boosting 8 psi with the boost designs stage 1 kit. for some reason. i start spooling around 3000 rpm and dont hit full boost till near 5000 rpm! whats going on? what can cause me to spool and boost so slow? would outside temps of 105 degrees make it spool slow? someone help me!

[TrunkMonkey]

what's the compressor trim?

-demetrius

[sunnys14]

.63 compressor

[Craving4Boost]

what gear? 1st gear might be a little fast so the rpm's can get high but 2nd and 3rd gear should boost around 3500rpm...

if it doesnt then you should probably recehck your IC pipings again..or use the DYI vacuum/boost leak test in the sticky

[Checkered-Member]

.63 compressor

That’s the size of the housing, what is the trim spec on the compressor wheel?

[C-Kwik]

Assuming the turbo is actually working properly, a t3 turbine should allow 8 psi fairly quickly, even with a larger trim turbine and a larger trim t04e compressor. I'd check for a wastegate that opens prematurely or is partially open all the time, or perhaps an exhaust leak.

[nissanfanatic]

Compressor wheel trim doesn't affect spool very dramatically. Given it will require higher impeller speed to deliver the mean airflow of a smaller trim wheel, this RPM change should be a split second difference. Nevertheless, boost should build until the wastegate opens after 3k. On my T04B, I hit full boost @ 4k, maybe slightly less and I run a .69ar turbine. You should not spool later than I. Check your exhaust manifold for leaks, check for exhaust restriction, check for a dirty air filter, check for boost leaks, check compression, and lastly, look at your impellers. Get back to us with the results to those inquiries.