[quote=Ian67I plan to buy a large (by eBay standards) intercooler with a black piping kit. The piping is 3" as the turbo is 3" so that is easy. My current exhaust system is nothing special and could use an overhaul I'm sure. Would I see a significant advantage in running a 3" downpipe to a new 3" exhaust system? Or would the 2.5" downpipe and current exhaust perform the same?

Also, what do we think of this for a downpipe: http://pages.ebay.com/motors/link/?nav=item.view&id=251316090929

I've seen flexible stainless tubing for air conditioners and other appliances but this says it's for vehicles and is 2.5" 304 stainless. Sure would make things easy :-)

Ian [/quote]
The 500 2BBL Holley will work fine.

I would run 3" downpipe & exhaust. Do not run that flex tubing. Garbage.
You will see an improvement in the turbo spooling up quicker running a free flowing exhaust system & intake system.
For exhaust and turbo apps, the bigger the better, you do not want any restrictions or back pressure.

I always recommend a muffler, straight through design.
For me I think running a exhaust system w/out a muffler sounds like a$$. But to each there own. Plus if you are driving in the city & the cops are out, no need to draw extra attention, & believe me, my Syclone is plenty loud when I get on it & I use a muffler, but, it is pretty quiet when just cruising around.

MBHD

12 port SDS EFI