tti headers

Call TTi. I bought mine for my 408. I called them and they asked me all kinds of questions. What block, what horsepower, what heads, what starter, etc.... I am running just over 500 horsepower and wanted to go 1 7/8 as well, but they talked me out of it because I don't have the horsepower to need 1 7/8 and if I used them it would cost me low end torque. I went with ceramic coated thermal 1 5/8 step headers. I love them. They work well, look like fairly new after three years, and I can access my spark plugs.