Would a larger A/R on the hot side help or worsen a slight boost creep issue?
T04e 57 .84 a/r p wheel to a 1.00 a/r. My understanding is that wastegate size and or runners effects boost control, however a discussion with a friend claimed a larger a/r might help.

 

A smaller A/R on your turbo won't cause boost creep, in fact, it should help to eliminate it being that it will choke your engines output and limit the ability to create boost. Hence why a stock TII turbo looses boost up top, there isn't a large enough housing (or compressor wheel for that matter) to hold max boost to redline.

Usually, boost creep indicates the wastegate isn't flowing enough for the engine's demands or its runner's are positioned in such a way that prevent the required amount of flow from happening.

 

dam looks like i was wrong on this one. i had the impression that a smaller a/r would direct airflow right to the turbine wheel and cause a slight boost creep/spike in the early rpm range due to the responce from the .84. i was confused, considering the wg size jack has and still getting boost creep should not happen. but i guess that is possible.

 

just an opinion here, but if you're having boost creep problems, then you should probably look into your wastegate (location, spring and size) and your manifold setup. larger turbine A/R may lessen your problem a bit, but it is by no means a relaible or advisable way to control your creep issues.