With the larger GT3 Throttle Body and IPD Plenum installed (see here) it was time to unbolt the factory headers and replace them with a stainless steel sport manifold set from Cargraphic. Another 12kw is expected from these very high quality headers. Below you'll see a factory manifold (left) and Cargraphic manifold (right) for comparison.

The GT4 is now off to the dyno for a tune; we’ll be sure to upload results and the next step of modifications for this black beauty.

If you're interested in upgrading your GT4 it's time to join in on the fun and call us on (02) 9417 0911 or drop us an email on