robinggood
Greenie N00B Member
Hello,I have a 2006 mazdaspeed6,fully built engine. The turbo is garrett GTX3582 gen II with a T3 0.82A/r twin scroll turbine housing.So I used dual 38mm external wastegates dumped to air.About 3900 rpm it hit rated boost to 15psi,but after 5000 rpm and the wastegates completely opened, the car doesn't push at all.Did I choose the wrong wastegates ?Were they too big?My tuner said so.But the log said Afr/spark/boost all seems healthy.
It only make about 240whp as you can see at high rev torque drop off seriously.My goal is shooting at 600 whp.In early time I tried single 44mm/single 60mm/dual 44mm.But all same trouble.
In early time,my car suffer slightly overboosting,so I rebuild 3 manifold to solve the problem.First is single 44mm wastegate,after 5000rpm,boost keep climbing upon with rev,from 15 psi to 20 psi until rev hit 6000.And then I change to a 60mm single.But maybe the manifold or wastegate angle it doesnt help.So I fabricated a new manifold and run dual 44mm wastegates.This time it doesn't go boost creeping,but as I said in high rpm causing power loss.Until now the 3rd manifold and dual 38mm wastegate still dont get power.I have checked spark plug.They seems running good and did compression test,still no problem.
The engine is fully built,forged CP piston,molnar rod,kelford camshaft with many other modifications. Maybe I should check some other things.
My engine block and some of the parts
Spark plug checked few days ago. Log file the last
It only make about 240whp as you can see at high rev torque drop off seriously.My goal is shooting at 600 whp.In early time I tried single 44mm/single 60mm/dual 44mm.But all same trouble.
In early time,my car suffer slightly overboosting,so I rebuild 3 manifold to solve the problem.First is single 44mm wastegate,after 5000rpm,boost keep climbing upon with rev,from 15 psi to 20 psi until rev hit 6000.And then I change to a 60mm single.But maybe the manifold or wastegate angle it doesnt help.So I fabricated a new manifold and run dual 44mm wastegates.This time it doesn't go boost creeping,but as I said in high rpm causing power loss.Until now the 3rd manifold and dual 38mm wastegate still dont get power.I have checked spark plug.They seems running good and did compression test,still no problem.
The engine is fully built,forged CP piston,molnar rod,kelford camshaft with many other modifications. Maybe I should check some other things.
My engine block and some of the parts
Spark plug checked few days ago. Log file the last