I am beginning to work on my 1984 T/A again. Over the past 4-5 years I have been slowly gathering what I thought I would need (including a set of these in the black painted version about four years ago).

http://store.summitracing.com/partde...&view=32&N=700+

Perhaps today the decision would have been different (maybe the 2055's), but after reviewing the exhaust board and stickies about the shorty header selections (pro's and con's, etc) I still believe I can utilize these for my 1984's 355 with excellent results. The engine makes about 300HP.

They are brand new and still in the box and since cost has already been sunk years back, I think they would still work very efficiently if I cutoff the single 2 1/4 collector pipe where the Y comes together and weld in a 3" mandrel bent 45 deg pipe. Seems like with this modification they should really flow well (and hook into my 3" flowmaster catback).

Bottom line is that I am going to work with what I have and would like to get it as efficient as possible.

What do you all think? Any other areas to modify for better flow?

 

Take a grinder and grind out the welds on the inside that hinder flow. And have them ceramic coated after you change the y-pipe as you said.

 

You mean right in the ports of the header where it meets the head, correct?

 

Yes, that is what I mean. The 1 5/8" header ends up being a 1 3/8" header from all the weld in that port.