Ported My ZO6 Throttlebody

[TODD L GRIFFITH]

I decided to port my throttlebody on my ZO6. I spent $12.00 at the hardware store, where I bought stone type grinder drill bits of different shapes, and a couple of sanding bits, one with 120 grit and another with 400 grit. I took my time and ported the inlet side first. You want to be careful not to take off too much, and to keep it smooth and uniform, take too much off and you will burn through the casting. The back side or discharge to the plenum you want to take off enough to enlarge the opening, but do not go beyond the line of the gasket on the plenum. Once you have taken off enough on either side, you can ground down the back side of the screws on the butterfly. After that is complete, use the corse sandpaper to make it smooth, shaping the opening and then the fine sandpaper to basically polish what you have taken off. Be sure to round off the inlet leading edge to reduce any turbulance that could be encountered by an abrupt transition. There is no need to enlarge the breather passage I have read, so keep away from that area. It took me about 1-1/2 hours being careful. If you have a high speed drill, it works best for making the job alot easier. The sanding bits are a barrel type. Try not to get ones that are too wide, so they fit below the butterfly at WOT position. After you are done, there will be alot of fine aluminum dust. Do not use water to wash the throttlebody off. It is best to use compressed air and then a lightly damp rag to wipe it clean. I have no idea what size the opening is, but I hope it is at least 85mm. If anyone has any questions, and would like to try this mod., feel free to ask.

[Dave C. '04 Z06]

What prompted you to port the throttle body?


-Dave C. '04 Z06

[Gorgon]

Let us know if you think this has yielded any noticable results. Not that I'd do the mod, it's more of a curiosity thing.

[TODD L GRIFFITH]

The reason for the porting was an article I read in Chevy High Performance Magazine on a 10hp gain realized on a LS1 Camaro. I figured I would try it and see what kind of a gain I could see, along with my aftermarket induction parts that consist of the Donaldson Blackwing, Power Duct, Granatelli MAF, Performance Hood Seal, and an 18"x12" inverted air scoop that grabs air from beneath the filter from the radiator enclosure area, a cool mod. in itself. Being a ZO6, I get air from the nose of the car too. I have larger injectors, plus the Diablosport Predator to do the tuning. Big air and fuel for combustion. The car does get up and go, I believe my throttle response has improved due to the porting. I drove the car this morning, and getting on the highway, on the ramp hit the century mark. A quick blast to test it out.

[TODD L GRIFFITH]

Gorgon, had alittle surging issue that got resolved by placing my old filter lid over the Blackwing, did the trick, forcing air into the filter from the bottom inverted air scoop for more of a ram air effect. Man the car just screws. The car even sounds alittle different when it is getting the air it needs for all that fuel with no turbulance. The car feels ALOT more powerful.

[Dave C. '04 Z06]

Cool!


-Dave C. '04 Z06