No you should be able to use a GD bov. Thing is, an 08 will require some extra work to make it fit nicely. Easiest solution is to buy a GD one.

As mentioned, ebay has heaps.

Subaru WRX STI GDB INTERCOOLER | eBay

sti topmount intercooler | eBay

sti topmount intercooler | eBay

GDA GDB Impreza WRX sti factory intercooler | eBay

GDA GDB Impreza WRX sti genuine intercooler | eBay

Also rising sun subaru should have heaps in stock.

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]