DIY Port n Polish Throttle Body

14th April 2009

I got myself a couple of spare TB and recently I got a new toy, the Dremel tool. Took this opportunity to port and polish the TB for better airflow at high rpm range.

The TB shown here is a 1.6 TB taken from 4G92 SOHC engine which the previous owner already ported the top part for better flow. Now i'm porting the entire TB and polishing it to mirror finish.

Original 1.6 TB, the previous owner ported the top part to improve airflow when the throttle plate opens 800x600	The bottom part is untouched 800x600	This is my new toy... the Dremel tool with suitable bits 800x600
First we start with porting the sharp edges with the grinding stone at moderate speed 800x600	Then smoothen the curves with sandpaper at low speed 800x600	Once the surface is smooth enough, polish the surface with felt and Autosol metal polish 800x600
Further polishing by using smaller felt tip. Throttle plate is also polished 800x600	The throttle plate is grounded to knife edge to give better airflow during partial throttle. Edges are polished to mirror finsih as well 800x600	Port n polish job completed 800x600
This is the comparison before and after 900x375	This is another set of TB taken from 4G93 DOHC engine 800x600	Camparison across 1.5, 1.6 n 1.8 TBs. Just a reference 800x439