The dual exhaust bolt holes are for ether W2 headers or the normal regular LA headers. Exhaust manifolds will also bolt up, but the port mis match is crazy. It still works fine. The exhaust isn’t as important or sensitive to bad port matching.
Most W2 head pipes are large as the head can flow a lot of air in and out, some tubes can be greater than 2 inches. Hedman makes the “Hustle Header” for the W2. They may also still have the adapter flanges. While it helps bolt up standard headers, there isn’t a huge gain in the ports flowing better, or much better. It does improve but.....
