What do you mean by longer throw? Do you mean gearing? If so, B16 gearing is shorter than GSR gearing. If you already have a GSR tranny, I would try that out before looking for a B16 tranny, especially with boost. See how you like the GSR tranny with boost, and keep in mind that shorter gearing will mean more shifting, and less time in boost. If you still want shorter gearing, also keep in mind that JDM trannies with 4.40 and 4.785 FD's can be had, and those have substantially shorter gearing.