Throttle Body Bypass Fiiting
Thread Starter
Instructor
Joined: Oct 2019
Posts: 139
Likes: 9
From: New York
Throttle Body Bypass Fiiting
Hi Guys,
I'm going to be rebuilding my throttle Body on my 85 and I see they sell the Bypass kit on-line for around $20.00 and I know the connector is two difference sizes. By all the threads I read doesn't state what sizes they are. I hate to spend $20.00 for a fitting and two hose clamps plus tax and shipping when I can over to Ace or Home Depot and get all three for way less. Note: I know not to use a nylon fittings. I'm thinking one size is 5/8" and it looks Like 3/4" but I not 100% sure.
I'm going to be rebuilding my throttle Body on my 85 and I see they sell the Bypass kit on-line for around $20.00 and I know the connector is two difference sizes. By all the threads I read doesn't state what sizes they are. I hate to spend $20.00 for a fitting and two hose clamps plus tax and shipping when I can over to Ace or Home Depot and get all three for way less. Note: I know not to use a nylon fittings. I'm thinking one size is 5/8" and it looks Like 3/4" but I not 100% sure.
Thread Starter
Instructor
Joined: Oct 2019
Posts: 139
Likes: 9
From: New York
I just did my by pass this morning, simple job, instead of joining the two 5/8" Hoses together with a splice. I decided to run a new hose from the fitting going to the heater it's right near the passenger tire side to the block. It's Impossible to make the bend with the hose without kinking it so I installed a 5/8" hose barb to 1/2" MPT 90 degree Elbow. My issue was turning the elbow a full turn. I needed to remove the temperature sensor and this made it possible to make a turn...
Melting Slicks
Joined: Oct 2016
Posts: 2,024
Likes: 363
From: Central Alabama
I used this one on my 92 5/8 x 1/2
But can't say for sure if all cars have the same hose sizes.
But can't say for sure if all cars have the same hose sizes.
7th Gear
Joined: Feb 2020
Posts: 7
Likes: 1
The water supply to the throttle body helps maintain a consistent temperature for proper fuel atomization under all operating conditions. Sometimes it actually cools the throttle body, while sometimes it brings the TB up to proper temp. For a race engine, you can ditch it. For a street engine, I'd leave it in place.
Safety Car
Joined: May 2001
Posts: 4,752
Likes: 1,642
From: Fairfax Virginia
I agree with mjlorenson on this issue.
I have had carburetor ice and sat on the side of the road while it melted and that is not fun. I have also experienced carburetor ice while flying and that is scary.
Anything that helps the atomization of the fuel is helpful and good for the engine. The Engineers at GM did not do this accidentally, it was very intentional and therefor they must have had a reason. They guys at GM wanted to make all the horsepower they could (reliably) for the Corvette and if they deemed it necessary to have a heated throttle body that is good enough for me.
By the way, Welcome to the Corvette Forum mjlorenson!
I have had carburetor ice and sat on the side of the road while it melted and that is not fun. I have also experienced carburetor ice while flying and that is scary.
Anything that helps the atomization of the fuel is helpful and good for the engine. The Engineers at GM did not do this accidentally, it was very intentional and therefor they must have had a reason. They guys at GM wanted to make all the horsepower they could (reliably) for the Corvette and if they deemed it necessary to have a heated throttle body that is good enough for me.
By the way, Welcome to the Corvette Forum mjlorenson!
Melting Slicks
Joined: May 2018
Posts: 2,091
Likes: 600
From: Question Government
I've also performed this simple T.B. Coolant Bypass mod. I knew I didn't need any extra heat in my TB since I live in moderate So Calif climate. The other advantage with this mod is not having any coolant drip over the engine and maybe on your Opti when removing the TB in the future.
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Melting Slicks
Joined: Jun 2011
Posts: 2,383
Likes: 385
From: Leland , North Carolina
I agree with mjlorenson on this issue.
I have had carburetor ice and sat on the side of the road while it melted and that is not fun. I have also experienced carburetor ice while flying and that is scary.
Anything that helps the atomization of the fuel is helpful and good for the engine. The Engineers at GM did not do this accidentally, it was very intentional and therefor they must have had a reason. They guys at GM wanted to make all the horsepower they could (reliably) for the Corvette and if they deemed it necessary to have a heated throttle body that is good enough for me.
By the way, Welcome to the Corvette Forum mjlorenson!
I have had carburetor ice and sat on the side of the road while it melted and that is not fun. I have also experienced carburetor ice while flying and that is scary.
Anything that helps the atomization of the fuel is helpful and good for the engine. The Engineers at GM did not do this accidentally, it was very intentional and therefor they must have had a reason. They guys at GM wanted to make all the horsepower they could (reliably) for the Corvette and if they deemed it necessary to have a heated throttle body that is good enough for me.
By the way, Welcome to the Corvette Forum mjlorenson!
Melting Slicks
Joined: Jul 2002
Posts: 2,223
Likes: 556
From: Tallahassee fl
The water supply to the throttle body helps maintain a consistent temperature for proper fuel atomization under all operating conditions. Sometimes it actually cools the throttle body, while sometimes it brings the TB up to proper temp. For a race engine, you can ditch it. For a street engine, I'd leave it in place.
Melting Slicks
Joined: May 2018
Posts: 2,091
Likes: 600
From: Question Government
It never cools it and colder air is always better going into the engine. GM put it there because the engine was designed to be used in all extremes... however, hardly anyone drives these things in extreme cold anyway. It's been tried and tested over and over... unless you are driving in extreme cold (sub zero) there is no worry and it adds a few HP for a few bucks.
