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Coolant bypass WARNING!

kwinsor

kwinsor

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Location
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A common performance MOD is the removal of the engine coolant loop from the throttle body. The theory is; cooler air will produce more power. It does work.

Don't worry if you are in a warm climate!

At 10 below zero I experienced throttle sticking. After travelling at a constant speed for 10 minutes the throttle wouldn't close completely!! Not a good thing when you are coming into traffic.

At first I thought it was the throttle cable that was sticking. I disconnected it to squirt in some WD40 and found that there was absolutely no drag on the cable.

It turned out that ice was forming on the throttle plate and not allowing it to close completely. If I snapped the throttle and let it close hard it would break off the ice and let it close fully.

I haven't reconnected the coolant lines because I know what to expect and it doesn't happen often.

Just be aware.

kw
 
Thanks for the GREAT info Redshift!!!  I haven't done that mod, but it's good to know why GM made it that way.
 
Yikes! Nothing like a stuck throttle to make you wet your pants. good to hear your OK.

BTW - Hope you received my check.
 
I had always assumed, that would be the possible result of this MOD. But, I was waiting to hear if it really happened to anyone.

Thanks, for passing along your results.

I've often thought about changing it back in winter time. But, sounded like a hassle. Then, I would try to conceive a valving possibility to make it easier. Oh well, I'll keep thinking.
 
I've had no problems with mine but Kentucky is quite a bit warmer than Maine.  We see 10 below about once every 3 or 4 years and then only for a few of hours at a time.
 
Will the removal of the engine coolant loop from the throttle body cause any other problems? like will the computer know it is not hooked up? I don't want to confuse it you know...lol

I had to unhook mine to put on a T&T PERFORMANCE SONIC HELIX BORE VORTEC THROTTLE BODY SPACER . Do these things really help?

I am going to put on a? Cold AIR INTAKE SYSTEM, and replace my factory exhaust with true dual exhaust with flowmasters. I know it will sound good, but will it help me get a few more MPG  ???
And will this cause me any problems with the computer?
 
Charlie,

You shouldn't have any problems unless you drive about 1500 miles north. The computer wont know that you have the coolant hoses off.

There hasn't been any evidence that the spacers do any good on a fuel injected system.

A cold air kit and exhaust work will increase your power and the computer will adjust on it's own.

If you want more power you can run 93 octane and get a plug in tuner!

kw
 
Redshift
I understand the theory of the coolant bypass mod, but does it really make a noticeable difference at all?
 
TNAV said:
Redshift
I understand the theory of the coolant bypass mod, but does it really make a noticeable difference at all?
Click to expand...

I'm not the performance guru that Redshift is but I can tell you that I couldn't tell any difference.  I figure if I can get 1 extra hp for the cost of 2 hose clamps why not. :cautious:
 
KY_BOB said:
TNAV said:
Redshift
I understand the theory of the coolant bypass mod, but does it really make a noticeable difference at all?
Click to expand...

I'm not the performance guru that Redshift is but I can tell you that I couldn't tell any difference.? I figure if I can get 1 extra hp for the cost of 2 hose clamps why not. :cautious:
Click to expand...
Hey Bob
Thanks for the reply kind of what I was thinking but you never know.
 
Just a little 1/4" brass hose connector from the auto parts store.  It's about 1 1/2" long and has barbs on both ends for the hose to clamp down to.  I also bought 2 rubber caps to seal off the TB where the hoses hook up but it's not really needed.
 
This is one of those mods that can't "make' horsepower but can prevent the loss of power.

A 10 degree increase in air temp causes a 1 % loss in power or about 3hp for every 10 degree increase in temp.

The intake air sensor is in the mass air flow sensor which is way before the throttle body. The computer will not know that you done the coolant bypass. The computer will not make any immediate adjustments.

The benefit of the coolant bypass come in on engines that are being pushed hard, have maximum timing advance for the fuel used and are running on a hot day.

Under any of these conditions there will likely be spark knock. Spark knock causes the computer to retard the ignition which reduces power.

A "hot" throttle body will add to these problems, the coolant bypass will help prevent the power reduction.

A cold air intake is before the intake air sensor so the computer knows it's working with cold air. It tries to make maximum power based on this information instead of reducing power when problems occur.

Both mods are a good combination if you don't have to worry about freeze up.

kw





 
I did the by-pass on my Impala but it would be an emergency for me to drive it in the winter. With my AV seeing -20 F up state Ny in the winter I would not risk it. Although I wonder if the throttle motor would have enough force to close throttle even with ice build up. I bet it does. :)
 
Has anyone thought of doing the reverse of what GM intended? Instead of putting a little heat there why not a little cold? I would think it would be easy to run a little cool air through that bypass hole, maybe something that could easily be shut off in the winter? A small line tapped into the air box with a shutoff valve comes to mind. You could hide it under the air feed going to the throttle body.

Butch
 
I did this mod with a twist!!

I left it all connected BUT I added a T-valve to the line.  In the summer I shut the valave which stops the collent from flwing through the TB.  When weather turns cold I just reach in and open it.

Volia best of both worlds.
 
BONEDOG said:
I did this mod with a twist!!

I left it all connected BUT I added a T-valve to the line.? In the summer I shut the valave which stops the collent from flwing through the TB.? When weather turns cold I just reach in and open it.

Volia best of both worlds.
Click to expand...

Good thinking :0: Thats a great idea :love:
 
and where did you get the valve?...part number?
 
I did it a few weeks ago...I just didn't use the valve set up....I kept the the little piece of hose just in case I go up north for the winter...it was easy, just get 2two 1/4" vacuum caps to make the throttlebody look good.
 
none that was noticable
 
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