Last night a took my resonator (air filter cover) off and made some mods that gave my TB some good, noticeable power. The first thing I did was use some parts-store generic, self-adhesive weather stripping to seal the gaps where the resonator meets the washer fluid resevoir. Second, I used a hole saw to make a hole for a 1 1/4" black vacuum cleaner hose in the "dirty air" half of the resonator to take advantage of the extra internal hole (I know it's not really extra, but my truck doesn't need to be that quiet!). Third, I put a rubber washer on the hose to make a good seal and then a large, black oil funnel on the other end. The funnel fits perfectly behind and over the grate where the fog lights are on the pricier models. I also left the OEM intake on the front of the resonator so that water is not able to be sucked or drafted up my cold air tube. No vacuum, just air forced-in by driving speed.
The result is forced, cold air going into the filter now and less hot air from the engine. I am very happy with my mod for the performance, inexpense, and professional look. The only thing you can see of this mod is an additional, automotive-looking hose going down towards the frame from the resonator when you lift the hood.:thumbsup:
Any pictures? That 1-1/4" tubing sounds small but the last 305 I worked on I do not recall seeing much more room than that. I also recall seeing some sort of intake opening between the filter and the resonator and an intake path molded in the air filter lid. Maybe the 305s are that much different but I doubt it??? Any chance of increasing that tube size? Did you drill the hole straight out next to the radiator support? Any path to duct down lower?
I'll get pictures loaded today if I can. The funnel I'm using is just big enough to wedge into the steel bumper hole and stay there. I didn't have to drill any holes other than the one in the resonator.
Looks like you might have room to squeeze a larger duct size if you have a hard 90 degree elbow off the stock box. Might want to check out spectre automotive products if you are still looking more for an automotive look. Might be able to find them in a local autoparts store. I know autozone carries some of these products on the spectre line.
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