Installing a 60mm Throttle Body on a 4g93

Step 1: Bore the Intake Manifold to match the 60mm 1G DSM Throttle Body

Stuff a shirt in the intake manifold

Bore the manifold to match the throttle body openning

60mm 1G DSM on left 50mm 4G 4g93 Mirage on right

Use an Impact Driver to remove the ISC screws. Much less chance of stripping the screws out

4g63 NA 1G DSM Throttle Body with ISC removed

4g93 Throttle Body with ISC removed

Finished Product

4g63 1G DSM ISC

4g93 4g Mirage ISC

Comparison Throttle Body Picture

4g93 ISC on top and 4g63 NA 1G DSM Throttle Body on bottom (top screw hole has to be silicone'd shut)

Filled part of the 1G NA TB Coolant Passage With JB Weld to keep from having air leaks. (notice the ISC on the bottom has a screw hole siliconed shut.)

Comparison of 4g93 ISC and 4g63 ISC gasket

File the top of the JB Weld flat and then silicone over the JB Weld and then put the rubber seal on. Next, screw the ISC to the throttle body

Adjust the TPS so that its resistance just barely maxes at closed TPS.

Adjust the throttle cable so the throttle body butterfly plate fully closes

Here is how I routed the vacuum lines

Tighten the BISS all the way down and then back it out 1 full turn. Drive it for 2 days and then adjust so idle is correct.

Picture of the 4g63 NA 1G DSM Throttle Body Installed on the 4g93