TA stock replacement headers

[TTipe]

I just purchased a set and they fit well. I'm concerned that the new headers may create more back pressure than my stockers did. I have ported GN1's and they do match up. Just looking for honest feedback to know if they will support a combo into the mid to high tens.

Thanks for the comments

 

[Eticket]

not sure why you think they would create more back-pressure than the stockers? the choke point the exhaust turbine wheel and housing, not the headers.

for reference, I have postons headers which are similar and have been low 10's.. stock, ta stockers or almost any decent headers are good into the 9's.

 

[we4Mateo]

^^^^^^x2, stockers are fine for your goals and your current headers should be better.

 

[TTipe]

^^^^^^x2, stockers are fine for your goals and your current headers should be better.

My stockers were cut open and the winking at the runner to log joints were massaged as req'd to eliminatve reversion. My iron heads have "D" shaped exhaust ports and would not match up exactly to my ported GN1's. From CFD it looks like port velocity and adjacent cylinder scavenging will improve but wall friction in the runners may not. The TA's fit well.