I have a holset hx55, I am installing on my silverado. Currently building the hot side. I am not sure what size they call this but I need to reduce down to 3.5" or 4" pipe!

Can you guys let me know what to look for?
The outside of the v-band ring measure close to 5". I don't know how to load a photo with my phone or I would post one. The inside of that measures a little less than 3.5

 

No expert on turbos but can help you post a pic. Assuming you have a smart phone get the photobucket app and setup an account and then you can copy and paste the img code from photobucket app to this thread

 

My Internet is so slow that I can't upload a picture photobucket! I have an account, just **** poor Internet!

 

not sure what your planning on for an engine but 3.5-4" is still pretty big

 

This size is for the exhaust out, the hit side going in I plan to use 3"