J30 Throttle Body By-Pass?

[GerryO]

The plenum is off now and by this Thursday (Wednesday is a looking for a job day) I should have the new injectors installed in the old fuel rails.

Does anyone have any experience with and/or instructions with photos regarding a throttle body by-pass specifically on a 1993 J30?

Thanks!

[gr8scott72]

Bypass of what?

[GerryO]

The throttle body coolant/water heating lines, along the lines of what's shown in these two photos.

Reportedly the throttle bodies are heated to prevent possible sticking/icing in very cold weather conditions.

[edgartheace]

I did this on my Z and it is the same procedure for the J30. If you look at the rear of the engine you will notice the two pipes that feed the Heater. These two pipes have two smaller pipes that come out of them and connect to the hoses on the plenum that feed to the throttle bodies. Take some small tubing. 1/4 diameter hose if I remember correctly. I used fuel line hose and just conectted the smaller pipes together with hose so that it would just circulate back into the cooling system and not the throttle bodies.

[yodawill2000]

Whats the benefit of doing this ??

[edgartheace]

For me at least it was avoiding the hassle of hoses under the plenum tearing, or rupturing, which was a pain in the @$$ on my 240sx, I can only imagine what it is like on the Z. Then there is also the argument that why would you put a CAI only to reheat the air at the throttle bodies and the plenum from the coolant hoses that pass through there. I wouldn't recommend it if you live in an area with -0 temps, since the coolant was circulated through the throttle bodies to avoid icing.

[gr8scott72]

For me at least it was avoiding the hassle of hoses under the plenum tearing, or rupturing, which was a pain in the @$$ on my 240sx, I can only imagine what it is like on the Z. Then there is also the argument that why would you put a CAI only to reheat the air at the throttle bodies and the plenum from the coolant hoses that pass through there. I wouldn't recommend it if you live in an area with -0 temps, since the coolant was circulated through the throttle bodies to avoid icing.

I can see doing it for the sake of not having to worry with the hoses but the argument of doing it to gain power, well, that's just silly. A VERY small portion of the TB is heated and it is only heated to keep it from freezing. You will in no way be able to tell the difference by seat of your pants dyno or even a real dyno by bypassing them.

[edgartheace]

Yeah, I dont see why people do it to add a pony or two as people claim it does. I just didn't want the hassle of replacing those hoses below, and living in SoCal I don't have to worry about freezing temps.