... if I can utilise the hole already provided in the HF manifold before my turbo or whether to drill a hole and weld a bung in the downpipe? Which would give me better readings? The engine is a d16a9 which means it has no stock o2 sensor so there is no stock location for an o2 sensor in the exhaust other than the HF manifold.
Any help would be greatly appriciated
Thanks in advance