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Discussion Starter #1
People has been asking me how i did my tb coolant line delete and the correct line size and adapters they should use so i decided to write a simple DIY post for future references.

Pros:.Cooler throttle body
.easier to remove throttle body since you dont need to wait for the engine to cool down due to the coolant lines attached to the throttle body.
.Also this is very easy so why not.
Cons:
.I guess areas that experience extremely cold weather may suffer from doing this mod because apparently the coolant keeps the throttle body butterfly from freezing up, but i never heard anyone saying that it happened before, just that its a possibility.

Required Materials:
30-60 Mins of labor
3/8" double barb ends
4 hose clamps


3ft of 3/8" fuel line


Step 1: Remove throttle body there's DIY in the forums that will show you how to remove the throttle body

Step 2: Remove the two hoses connected to the throttle body.





Step 3: Put the barb adapters into the fuel line and cut the line to the length you want as long as you can connect it to the other port.



Step 4: Make sure everything is clamped down. you dont want this to be leaking on you.



Step 5: enjoy the cooler throttle body and the ease when changing spark plugs.
 

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People has been asking me how i did my tb coolant line delete and the correct line size and adapters they should use so i decided to write a simple DIY post for future references.



Pros:.Cooler throttle body

.easier to remove throttle body since you dont need to wait for the engine to cool down due to the coolant lines attached to the throttle body.

.Also this is very easy so why not.

Cons:

.I guess areas that experience extremely cold weather may suffer from doing this mod because apparently the coolant keeps the throttle body butterfly from freezing up, but i never heard anyone saying that it happened before, just that its a possibility.



Required Materials:

30-60 Mins of labor

3/8" double barb ends

4 hose clamps



Vaper 19345 3/8" Hose Mender - Air Tool Fittings - Amazon.com



3ft of 3/8" fuel line



Amazon.com: Allstar Performance (ALL40356) Fuel Line, 3/8" x 3': Automotive



Step 1: Remove throttle body there's DIY in the forums that will show you how to remove the throttle body



Step 2: Remove the two hoses connected to the throttle body.











Step 3: Put the barb adapters into the fuel line and cut the line to the length you want as long as you can connect it to the other port.







Step 4: Make sure everything is clamped down. you dont want this to be leaking on you.







Step 5: enjoy the cooler throttle body and the ease when changing spark plugs.

Great write up but your catch can is a fire hazard.


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yea needa relocate it somewhere. The catchcan never fills up with oil at all tho.

I've never noticed a massive amount of oil come through that line. It's fairly low pressure air. I would hook a catch can up to the one on the other side of the throttle body.

I swapped to a 80mm gs throttle body so I'm running all the vacuum lines to a block>catch can>back to the engine that way I can catch oil coming from any port. The one you have it hooked up to I just have a breather filter on.


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great write up man , when there is some free time ill pop the hood and get to it , i live in a hot area already so this will out whenever i wanna clean the throttle etc...
 

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People has been asking me how i did my tb coolant line delete and the correct line size and adapters they should use so i decided to write a simple DIY post for future references.

Pros:.Cooler throttle body
.easier to remove throttle body since you dont need to wait for the engine to cool down due to the coolant lines attached to the throttle body.
.Also this is very easy so why not.
Cons:
.I guess areas that experience extremely cold weather may suffer from doing this mod because apparently the coolant keeps the throttle body butterfly from freezing up, but i never heard anyone saying that it happened before, just that its a possibility.
Is the hose then resting on the valve covers? No issues with heat or anything?
 

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Discussion Starter #7
Is the hose then resting on the valve covers? No issues with heat or anything?
the hose is wedged between the TCM and the engine cover mount, in this picture its on the valve cover i dont think it would matter. No issues with heat at all.
 

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I've never noticed a massive amount of oil come through that line. It's fairly low pressure air. I would hook a catch can up to the one on the other side of the throttle body.

I swapped to a 80mm gs throttle body so I'm running all the vacuum lines to a block>catch can>back to the engine that way I can catch oil coming from any port. The one you have it hooked up to I just have a breather filter on.


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gs400???
 

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I might be doing this. I think mine TB ic clogged. Whenever I blow air from one end, it doesn't come out the other end. I was wondering if it will effect anything but obviously not. Thank you
 

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I want to raise the dead on this because I believe I have some constructive information to add.

I have 2 is300's. One turbo and one completely stock. On the turbo one I bypassed the TB from the beginning and I have a GM temp sensor tapped to the front of the intake manifold above the Vac line.

I'm in the process of switching everything over as the completely stock one has always been much cleaner and has AC.

Ive been chasing my tail trying to figure out why my stock is300 has so much higher iat in general and more noticeably at idle and cruise. They are setup the same. I thought that maybe I damaged the iat sensor in swapping it over. My last hope was hoping that the coolant in the TB was warming the air enough to make the such drastic differences. It is totally confirmed that the coolant is pulling for its temp at 180(engine temp), the incoming air is pulling heat from the TB and gets to 150+ quickly at idle inside the runners on a 80 degree day. With the coolant bypassed the air still gets hot but not nearly as hot and as fast, and it cruises 5-15 above ambient in the runners.

Its negligible on power but the tune was sure enough skewing with with excessive induced temps from the coolant as the temp swings were huge from low to high air flow. I'm back stable with it gone.

Side note, it hardly ever gets below freezing in the south.
 
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