Set Self Tuning Thread Pool Minimum Size?

Currently on 10.0 we have an application (ear) that contains a web app with a
JAX-WS web service that simply writes to a persistent queue and ejb-jar with
MDB's that read from it and does some JDBC work.

We have a:
HTTP Work Manager with a Min Threads Constraint of 50 and a response time goal
of 50ms.
EJB Work Manager with a Min Threads Constraint of 80 and a Max Thread Constraint
of 80 and a response time goal of 500ms (we had even worse results without this
second goal)

Our MDB pool size is 80 and our JDBC pool size is 80

The issue is that no matter what we do we can't get the server to respond to
HTTP requests quick enough on server startup (i.e. < 100ms). We suspect it's
related to the self tuning thread pool not spawning threads until it's too late.
On startup the self tuning thread pool is at 75...

Is there a way to force WebLogic to have a certain number of threads as a
minimum in the self tuning thread pool (i.e. for us it would be
50+120+<whatever server needs>)? It's obvious the work managers are a
"recommendation"