Throttle Body Coolant Bypass
Edit s_tim_ulate: Please research the benefits yourself before undertaking this... nevertheless...
As the title suggest, this modification will bypass the coolant that passes in throttle body which in turn will benefit the air that passes through the intake manifold.

Under the normal engine operation and during this summer season, the coolant temperature reaches the boiling point and that same coolant passes through and heated the throttle body. This operation is very beneficial during the cold season, but during summer? I don’t think so…

This modification is 100% effective than buying an expensive gasket. This will cost you only a few dollars or even nothing if you have all the materials needed. The good thing about it is that anyone can do it in 1 hour or less.

Tools needed:

Pliers
+ and - screw driver
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Materials:
30cm length - 9mm fuel hose
2 - 8mm bolt
Teflon tape
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1. Remove the intake pipe from the throttle body and anything that you think will help you to move freely like the vacuum hose wiring etc.

This photo will show you the location of the coolant inlet
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool2.jpg
and coolant outlet from the throttle body
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool3.jpg

2. Grab one of your 8mm bolt and wrap it with teflon tape, make it thick so it will be tight fit and the hose won’t damage.
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool6.jpg

3. Remove the hose connection to the throttle body inlet and shut off with the bolt you prepared and clamp.

http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool7.jpg

4. Do it the same with the outlet hose. Make sure you pointed up the hose so that the coolant won't spill too much.

http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool5.jpg

5. Grab the fuel hose and connect to the coolant inlet and the other end to the coolant outlet of the throttle body then clamp.
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool8.jpg

This is to give you an idea how it will be.
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool.jpg

6. Return everything.
http://i122.photobucket.com/albums/o248/MagnaTech07/coolbypass/cool9.jpg

7. If you spilled a lot of coolant during this process, make sure to fill-up before starting the engine.

7.a Re-set the ECU (edited to include this step)

8. Start the engine to check for possible leak.

9. Drive around until the engine heats up, and then check again for leak.

10. Slowly touch the throttle body…it’s a lot cooler than before isn't it?

NOTE: Make sure to reconnect it from the original connection during cold season.
This is not a go fast modifications so don’t expect it, although some people noticed a gain after doing it.

water cools better than air

a better way around it if you think its a problem is run a oil cooler before the water enters the throttle body

All comments, suggestions, criticisms are welcome, please post:nuts:

That coolant channel through the valve body is there for a reason and the problems you will get short and long term will overide the short term gains you get in performance....

water cools better than air

a better way around it if you think its a problem is run a oil cooler before the water enters the throttle body

I agree water cools better than air, but for the water 100deg+ that runs in the TB... I would rather shut it off during summer time. Cooler is a nice one but I'm always after for cheap/free and easy mod.

Peace

Couldn't you just plumb a valve into the coolant inlet line just before the TB, so that you simply turn it on and off as needed?

Correct. The throttle body is heated for a few reasons...

1) Stops the throttle possibly icing up in winter (not really a problem in Australia)
2) Very important - Stops the PCV vapours from condensing on the throttle body and jamming up the throttle blade - a very effective way to 'un-highflow' a throttle body.

But if you were to make sure you remove the throttlebody regularly and remove the deposits from the blade/body, you should technically be OK.

Cheers
Heath Young

Couldn't you just plumb a valve into the coolant inlet line just before the TB, so that you simply turn it on and off as needed?
Yeah, some ppl do it but I'm after for the a free mod. This mod cost me nothing since I already got the things needed.

Yeah, some ppl do it but I'm after for the a free mod. This mod cost me nothing since I already got the things needed.

Thats fair enough. You could probably find a suitable valve for the price of a big mac.

I'm curious as to exactly what is the purpose of connecting the 30cm length of fuel hose in a "loop" from the inlet - outlet.

Other than being an attempt to keep everything looking stock, I can't see any reason why it can't be left with nothing hooked up to the inlet / outlet.

I'm curious as to exactly what is the purpose of connecting the 30cm length of fuel hose in a "loop" from the inlet - outlet.

Other than being an attempt to keep everything looking stock, I can't see any reason why it can't be left with nothing hooked up to the inlet / outlet.

Nothing really, just to keep it away from dirt to come in. Any cap that will fit will do the job:D

Nothing really, just to keep it away from dirt to come in. Any cap that will fit will do the job:D

Where is the dirt going to go if it gets in there?

Where is the dirt going to go if it gets in there?

Most likely through your cooling system once you revert back to the stock setup. :D

Where is the dirt going to go if it gets in there?
Of course you know the answer to that question...are you trying to test me?:D
Anyway, if you are expecting me to say that it will go in the intake manifold, I'm sorry I failed you.


Most likely through your cooling system once you revert back to the stock setup. :D

You're a champ mate

Also, I'm not suggesting or recommending this to anyone.

Rather than blocking the lines, you probably would have been better off joining them together. Similar to when u bypass a heater core. Any blockage in a system isnt going to be as good as it being free flowing.

The coolant in the TB controls the wax fast air idle valve. This raises your rpm when the car is cold to help it warm up. also the design helps in increasing the rate of air flow as hotter air moves faster. So while colder air is coming in via your intake piping, when it hits the TB it is heated and therefore speeds up. The higher temp also assists in fuel vapourisation, this is why EFI cars run alot hotter than Carby cars.

Car companies dont put these sorts of things in for no reason (although many have all sorts of useless gizmos). Admittedly i did try this on some cars a couple years ago and in the end i put it back to how it was as it worked better. Initially it sounds good "the more cold air, the better" but i found this is not the case. Each to their own i guess, just letting u know what i found.

Rather than blocking the lines, you probably would have been better off joining them together. Similar to when u bypass a heater core. Any blockage in a system isnt going to be as good as it being free flowing.

The coolant in the TB controls the wax fast air idle valve. This raises your rpm when the car is cold to help it warm up. also the design helps in increasing the rate of air flow as hotter air moves faster. So while colder air is coming in via your intake piping, when it hits the TB it is heated and therefore speeds up. The higher temp also assists in fuel vapourisation, this is why EFI cars run alot hotter than Carby cars.

Car companies dont put these sorts of things in for no reason (although many have all sorts of useless gizmos). Admittedly i did try this on some cars a couple years ago and in the end i put it back to how it was as it worked better. Initially it sounds good "the more cold air, the better" but i found this is not the case. Each to their own i guess, just letting u know what i found.

Ha ha ha, so what's the use of cold air intake then if you will heated it with your TB?
The air sensor reads the volume and temperature of air intake, if you heated the air in the throttle body as you said it is, do you think the ecu will give an accurate fuel mixture?
True hot air moves faster, but heated the air in the TB...False. That might not be the purpose.

Hi guys

IMO MagTech's idea seems quite reasonable.

AFAIK the only reason the coolant is flowing there is to operate the the thermostat in the fast idle air valve like Matt says, and a bit of intake heating in cold conditions.

I'd take a bet that in most of the weather conditions we get,that FIAV is closed...with idle at startup controlled by the ISC motor. Probably only active or necessary in really cold conditions,maybe that also applies to heating the throttle body too, but couldn't find any specs at what temp the FIAV operates. So effectiveness might depend on your local climate, I guess the designers have to make the systems work in all possible conditions.

Another thing is the construction of the FIAV, there isn't all that much keeping the coolant and air inlet apart. So anything to avoid corrosion would be good, and that might be an issue if the coolant flow was turned off with a tap. Leaves stagnant coolant in the FIAV valve.:doubt:

How about a thermo valve in the coolant feed which turns off when it gets to running temperature. Just a thought.:D

Not sure where you get the idea the coolant runs at 100+. It doesn't boil since you run coolant to stop the boiling effect.

Ha ha ha, so what's the use of cold air intake then if you will heated it with your TB?
The air sensor reads the volume and temperature of air intake, if you heated the air in the throttle body as you said it is, do you think the ecu will give an accurate fuel mixture?
True hot air moves faster, but heated the air in the TB...False. That might not be the purpose.

I'm not gonna sit here and argue with you, i roadtested this on 2 cars, and from what I found they both ran better and used less fuel with it plugged in. The magna was less affected, but the 1997 323 Mazda, was running like a heap of **** with this bypassed, and using upto 2l/100 more, which i checked over 4 tanks of fuel.

So whats the use of cold-air intake if its gonna be heated? I dont know why dont you ask why mitsubishi fitted a factory cold air-intake to the 3rd gens (which also run coolant through the t/b), even the 2nd gen collects air from behind the headlight.

The air sensor does read the volume and temp like u said, but more noteably it does this BEFORE the throttle body. Much like the "resonator box mod (please dont get me started on this one)" which is also before the throttle body but after the sensor. Do you think that car manufacturers design/tune their ecu's, and then once all the tuning has been done decide "hey we're gonna put some bigass boxes in this air intake, and now plug in some coolant to the throttle body".
I think u'll find that the factory ecu takes all this into account.
But each to their own. If it makes u feel better by having a bigger "mod" list, then by all means.
I tried it, i didnt like it, so i put it back how it was. You asked for comments/criticism surely u werent expecting everyone to agree with you.

Hi jbman
It's a pressurised cooling system when it's working OK, and boiling point would be 100+ even with plain water, higher with the coolant mix. But I'd say it was an overheat condition if it was that high! I'd be worried :shock:

You asked for comments/criticism surely u werent expecting everyone to agree with you. I agree with you on this, just the same, you weren't expecting everyone to agree with you.

Peace :redface:

Wax? Mine has a thermo spring there.... Strange.


The coolant in the TB controls the wax fast air idle valve.

Not sure where you get the idea the coolant runs at 100+. It doesn't boil since you run coolant to stop the boiling effect.
Go and put your hand on your engine block.

No really, do it.

Now that you have successfully scalded your hand, you will realise that the engine heats up an enormous amount due to the internal combustion, and the only thing keeping it from cooking is the water cooling system, which is stored and moved under pressure. This pressure raises the boiling point to above 100 degrees (if water is used) and further still if engine coolant is used.

I say this a lot on this forum, but this thread is a load of rubbish.

Do a calculation on how quickly the air passes through a throttle, and how much heat is lost through the throttle itself.

It is very fast and absolutely none.

I say this a lot on this forum, but this thread is a load of rubbish.

Do a calculation on how quickly the air passes through a throttle, and how much heat is lost through the throttle itself.

It is very fast and absolutely none.

Yeah, so much rubbish...:D and you are still putting more...:D

Can't take constructive criticism?

Sure I can:D

Hmm.. not a big fan of the blockage method. What happens once the bolt becomes loose later on down the track.

I'd actually say that the majority of the intake air temperature change occurs in the plenum chamber and inlet runners more than anywhere else. Couldn't see the TB really doing a whole lot, but if you can live with the fast idle, then i guess why not..

The method is fine, the practice or results are what I questioned.

I figure, if CAMS officials let me race with bolts blanking off some fuel returns, then it must be a decient method lol

Another rubbish : Mod #6 http://www.ultimateresourceguides.com/content/freemods/92-96prelude-freemods.html

A: Dyno's are hardly a credible item
B: The results of any test have to be repeatable, 1 dyno sheet with no actual proceedure or definitive evidence... pulease.
C: Do you listen to oil manufacturers when they claim better fuel econ and power from special oil additives.

How many Hi-clones do you have, or shouldn't I mention that for fear of being banned :doubt:

And another http://www.ws6.com/mod-8.htm

And another http://www.ws6.com/mod-8.htm

For the sake of around 5HP (and I'm guessing thats a 'best case scenario') ... and a (potentially) even rougher idle...

...I'd rather watch TV. Or buy one of those 15HP+ chips off ebay.

:D

But hey, if you can bothered doing it, thats cool!

it takes 50X more air to kool a vw motor than it would if it was water cooled

that means they had to gear the engine fan to blow like hell
if you take the belt off one of these motors you gain aprox 10 to 15 kw

the only way your mod is going to convince people is to measure the temp of the tbody and intake air before and after.

like i said earlia a better way would be to use a auto oil cooler mount it in front ot the radiator and then work out which way the water flows and hook it up to the cooler

if the coolant temp is 100degC after running through a cooler you may drop a few deg keeping the tbody cooler than the motor.

eg. of water cooling.

run car for 10 min and run a big ass fan over a muffler, touch a muffler, hmmm hot as hell
run car for 10 min wirh water running over muffler. well would you look at that you can hold on to it.

it takes 50X more air to kool a vw motor than it would if it was water cooled

that means they had to gear the engine fan to blow like hell
if you take the belt off one of these motors you gain aprox 10 to 15 kw

the only way your mod is going to convince people is to measure the temp of the tbody and intake air before and after.

like i said earlia a better way would be to use a auto oil cooler mount it in front ot the radiator and then work out which way the water flows and hook it up to the cooler

if the coolant temp is 100degC after running through a cooler you may drop a few deg keeping the tbody cooler than the motor.

eg. of water cooling.

run car for 10 min and run a big ass fan over a muffler, touch a muffler, hmmm hot as hell
run car for 10 min wirh water running over muffler. well would you look at that you can hold on to it.


Good point there...

How about in the actual scenario:

run car for 1hr with the coolant running in TB., touch the TB , hmmm hot as hell
run car for 1hr without coolant running in TB, well would you look at that you can hold on to it.

For the sake of around 5HP (and I'm guessing thats a 'best case scenario') ... and a (potentially) even rougher idle...

...I'd rather watch TV. Or buy one of those 15HP+ chips off ebay.

:D

But hey, if you can bothered doing it, thats cool!

Good point...
Yeah rough idle can be expected for the first few minutes, but as your engine gets hot cooler air gets in and smooth idling can also be expected. And most important, this mod is FREE or almost FREE and easy to make unlike expensive chips.

I think I already said enough on this topic, and after all it's my car .:D :D
I'm just showing you guys how to messed-up a magna, ha ha ha... at least it's magna and not any other car...
I'm done here.

Peace

Hey, as long as you happy thats al that counts. :D

I like the idea matey. Some of the response are why I have stopped reading these forums so much. Unless you pay someone big money to do something most here seem to just bag you out <sighs>

People tend to forget that when motors like this are designed they are designed to work in a large range of conditions and in a few different weights of cars. The engineers try to cover all aspects of it so they do not have to change little things every time the motor is used in a different vehicle or region. Watch someone will come along are call that bull**** as well <grins>

In the sort time you have been posting I have seen you come up with alot more ideas and even better you are willing to try things and experiment yourself ! And you just aren't punking money down for someone to do the work for you !

Ok I am getting off my high horse before I fall off <grins> and going back to boring out my TB and custom made butterfly that according to some simply will not work cause I never paid to have it done ! <laughs>

/em dons his flame retardant suit

Keep up the great work mate!

Cheers
Jypster

/em dons his flame retardant suit
Dude you've been here like 2 months :bowrofl:

This thread is made of fail and lulz

Jypster. Agree with u. If we ppl never tried various things and experiment with them - I guess us humans would still live in caves (and drive VK Commodores).
What comes to this specific issue, I claim that it is prolly not very significant mod, compared to getting the plenum it self to stay cool etc. Regardless, I fully support such ideas and experiments. See, I don't like VKs or caves.....:D
Keep them coming!
Now, since I mentioned it. Hot plenum? The insulating gasket doesn't prolly help much cos the heat stays in the engine bay, regardless if the item is connected to motor or not. My strut brace gets hot soon after - and has nothing to do with insulations. Ideas? Heat exhaust vents? Scoop to ventilate the plenum?

Instead of feeling how how the Throttle body is you should feel how hot the air is on the other side, the difference will be un-measurable. All you are doing is removing features of the car, hell why not take out the air filter as it is just a flow restriction....

hell why not take out the air filter as it is just a flow restriction....

OH MY GOD IM GONNA DO IT. WHAT A GREAT IDEA.

lol i drove a car for 2 years without a airfilter motor ran fine even after 2 years