drifterextreme;286402 wrote:
still think it is crazy it makes 4 psi without the wastegate on at all.

that has some serious flow issues through that wastegate elbow then. Thats nuts

guy was trying to run 7 lbs and was creeping to 10-11 lbs. Also he is running stock redline 7200 and map sensor.

So i had mentioned switching to the small a/r as it will spool sooner and help wastegate flow. all the larger housing will do in this case is slow down the turbine and increase lag.

So there might be 2 ways to go about solving the problem. but in this case i think the smaller a/r is the way to go.

still think it is crazy it makes 4 psi without the wastegate on at all.

I had argued that increasing would, for the above reasoning

the other FS member argued decreasing it would for the above reasoning

not gonna say who it was unless he wants to say something or argue his logic here in this thread

zbrown;286315 wrote:
obviously i know that other changes would be more beneficial.... This was strictly a philosophical question of if you could only change the turbine housing ar; nothing else.

Which change by either going bigger or smaller would help with the problem

bigger

PSI2HI;286299 wrote:
Where's the neither option? Both have decreasing benefits in their perspective applications.

Smaller AR creating backpressure it going to kill poweroutput/powerband and lower the effiency, thus creating heat, and large AR is is also going to midrange poweroutput/spool.

I vote C. Make the wastegate work correctly in its current application.

SPANISH-RICE;286302 wrote:
for a lack of better words i agree with this. Get a properly matched waste gate and solve boost creep with that. If you're having issues with boost creep instead of swapping housings get a bigger waste gate/dump tube that can flow enough.

I think argument a is very incorrect tho. Increasing back pressure before the turbo isn't making the waste gate more efficient its just making it work harder and have to flow more.

Obviously i know that other changes would be more beneficial.... This was strictly a philosophical question of if you could only change the turbine housing AR; NOTHING else.

which change by either going bigger or smaller would help with the problem

psi2hi;286299 wrote:
where's the neither option? Both have decreasing benefits in their perspective applications.

Smaller ar creating backpressure it going to kill poweroutput/powerband and lower the effiency, thus creating heat, and large ar is is also going to midrange poweroutput/spool.

I vote c. Make the wastegate work correctly in its current application.

for a lack of better words i agree with this. Get a properly matched waste gate and solve boost creep with that. If you're having issues with boost creep instead of swapping housings get a bigger waste gate/dump tube that can flow enough.

I think argument a is very incorrect tho. Increasing back pressure before the turbo isn't making the waste gate more efficient its just making it work harder and have to flow more.

Smaller AR creating backpressure it going to kill poweroutput/powerband and lower the effiency, thus creating heat, and large AR is is also going to midrange poweroutput/spool.

I vote C. Make the wastegate work correctly in its current application.