Coolant bypass...mod?
- Thread starter BlkZoomZoom
- Start date
wicked said:
The following is a post on a forum about bypassing the TB coolant loop on GM engines (the duke was a 2.5L 4cyl, and the other engine is the 2.8L V6). The guy that posted this is one of the most knowledgeable guys on that forum. I usually agree with his advise, so check this out...
Originally Posted by wicked
the coolent runs through there for smog reasons,not to stop the throttle body from freezing.the idea is to expand some os the nitrogen molecules before they go into the intake to as to better atomize the fuel,it won't hurt anything,but it will only help(in horse power) when the car has fully warmed,and is in closed loop.
I'm not making this up,this realy is what it's for.
The following is a post on a forum about bypassing the TB coolant loop on GM engines (the duke was a 2.5L 4cyl, and the other engine is the 2.8L V6). The guy that posted this is one of the most knowledgeable guys on that forum. I usually agree with his advise, so check this out...
Quote:
Actually, the coolant travels straight through the bottom of the throttle body, it's a straight shot. As a result it only warms the small bit of the throttle bore that is directly below the throttle blade itself, and has no effect on the rest of the throttle body. The only purpose of this small amount of heating is to prevent a buildup of ice that could stick the throttle blade open causing a runaway throttle incident. The likelyhood of this icing actually ocurring is really quite small, but apparently GM thought it was important enough to spend engineering and manufacturing dollars to add the system.
Heating intake air only matters on engines where the fuel is mixed with the air somewhere other than at the valve. The Duke, for instance, mixes the fuel at the top of the intake so the intake charge is "wet" with fuel. Heating this air helps atomize the fuel better so that the car will get more power, better gas mileage, and produce less emissions. The intake charge on the Fiero V6 is "dry" because the fuel is added at the valve. In fact, the injector fires multiple times against the back of the closed valve where it sits and evaporates. Because the air charge is dry, it is best to keep the intake charge as cold as possible to increase power, efficiency, gas mileage, yadda yadda.
I get what he's trying to say,and it's true.TB injection,and carb vehicles must heat the a/f charge,thats known,or else they won't atomize for s***.that is incorperated into all wet manifolds.
but dry manifolds like all port,and cis injection cars don't.
but he says that "Heating intake air only matters on engines where the fuel is mixed with the air somewhere other than at the valve."
and thats not true,because this has nothing to do with the atomizing of the fuel,instead it's pre expanding nitrogen(witch is 70% of our atmosphere),causeing the engine to have less to burn,=less emisions.since it's lowering NO it also helps reduce NOx(oxides of nitroge) witch is cause by engine temps exceeding 2500 deg.were they become completely uncontrolableand O2 and NO combined,then we detonate =(.
if your laking NO to make NOx you save a lot of smog
(you fart less,when you breath less.)
the coolent runs through there for smog reasons,not to stop the throttle body from freezing.the idea is to expand some os the nitrogen molecules before they go into the intake to as to better atomize the fuel,it won't hurt anything,but it will only help(in horse power) when the car has fully warmed,and is in closed loop.
I'm not making this up,this realy is what it's for.
The following is a post on a forum about bypassing the TB coolant loop on GM engines (the duke was a 2.5L 4cyl, and the other engine is the 2.8L V6). The guy that posted this is one of the most knowledgeable guys on that forum. I usually agree with his advise, so check this out...
Quote:
Actually, the coolant travels straight through the bottom of the throttle body, it's a straight shot. As a result it only warms the small bit of the throttle bore that is directly below the throttle blade itself, and has no effect on the rest of the throttle body. The only purpose of this small amount of heating is to prevent a buildup of ice that could stick the throttle blade open causing a runaway throttle incident. The likelyhood of this icing actually ocurring is really quite small, but apparently GM thought it was important enough to spend engineering and manufacturing dollars to add the system.
Heating intake air only matters on engines where the fuel is mixed with the air somewhere other than at the valve. The Duke, for instance, mixes the fuel at the top of the intake so the intake charge is "wet" with fuel. Heating this air helps atomize the fuel better so that the car will get more power, better gas mileage, and produce less emissions. The intake charge on the Fiero V6 is "dry" because the fuel is added at the valve. In fact, the injector fires multiple times against the back of the closed valve where it sits and evaporates. Because the air charge is dry, it is best to keep the intake charge as cold as possible to increase power, efficiency, gas mileage, yadda yadda.
I get what he's trying to say,and it's true.TB injection,and carb vehicles must heat the a/f charge,thats known,or else they won't atomize for s***.that is incorperated into all wet manifolds.
but dry manifolds like all port,and cis injection cars don't.
but he says that "Heating intake air only matters on engines where the fuel is mixed with the air somewhere other than at the valve."
and thats not true,because this has nothing to do with the atomizing of the fuel,instead it's pre expanding nitrogen(witch is 70% of our atmosphere),causeing the engine to have less to burn,=less emisions.since it's lowering NO it also helps reduce NOx(oxides of nitroge) witch is cause by engine temps exceeding 2500 deg.were they become completely uncontrolableand O2 and NO combined,then we detonate =(.
if your laking NO to make NOx you save a lot of smog
(you fart less,when you breath less.)
I'm going to look into this further. I'd like to figure this out...
If you expand the nitrogen, the rest of the air (30% which is CO2 and O2, etc.) is also expanded.... the amounts of N2 and O2 don't change, but the pressure increases, or actually, the negative pressure in the intake manifold would be less negative (increased).
If you expand the nitrogen, the rest of the air (30% which is CO2 and O2, etc.) is also expanded.... the amounts of N2 and O2 don't change, but the pressure increases, or actually, the negative pressure in the intake manifold would be less negative (increased).
but you sort of got it.it's only purpose is for under idle.and it's trying to reduce the amout of 02 that passes the IAC.to help values stay at below 1% CO,below 1% 02,below 30 HC,and above 13% CO2iluvmacs said:
O2 is 21% atmosphere
the difference is that O2 and CO2 doesn't expand under such low temps.
and the nitrogen doesn't burn under combustion.so what it's doing is the same as a EGR,but at idle
this can be a bad thing if you ran slightly lean,say stoichiometric(14.7-1).it would be increasing detanation since you would have high levels of 02 you would be giving the exta nitrogen something to bond to,creating more NOx.also lowering your C0 level,and raising your HC's.
you would fail SMOG
sorry if this sounds like ramble,but have a very hard time typing what I'm thinking.
This is the last thing I'm going to say about this. I can understand how it could be cost effective for a car manufacturer to spend engineering time and parts (and assembly line time) to reduce an minute amount of emissions. However, I can't understand how someone would consider a small amount of destructive gas emission important enough to start a conversation about. That said, most people spend a lot more time sitting in traffic (at idle) than I do.
I'd be the last person to shirk our responsibilities to the environment, but lets drop this issue.
Removing the TB coolant lines has signifigantly reduced my under-hood temperatures (intake is ice cold after a long period of driving) and I'll never put the lines back.
I'd be the last person to shirk our responsibilities to the environment, but lets drop this issue.
Removing the TB coolant lines has signifigantly reduced my under-hood temperatures (intake is ice cold after a long period of driving) and I'll never put the lines back.
- :
- Hemi Ram, 71 Plymth Scamp, 71 Plymth Duster 340, 69 Dart 340/4sp
lol.
Puckpimp71
Member
- :
- 1991 Taurus SHO, 2003 Black Mazdaspeed Protege
Now get some spacers in there. I used to grill porterhouses on my intake manifold. Now I can barely warm my hands. 
flat_black
Member
Yeah, I kinda miss my super hot intake manifold; I used to use it to keep warm in the winter!
Puckpimp71
Member
- :
- 1991 Taurus SHO, 2003 Black Mazdaspeed Protege
It keeps heat from the engine from conducting onto the carb/TB so incoming air is a little more cool. There's probably something I'm missing here, but it's a good way to keep engine temps down a bit and squeeze out a few more ponies.
- :
- MP5T / 944
Ok, so in my quest to rip apart the MP5T, I noticed that the throttle body
is heated by coolant. I'm thinking that this is for the winter and to keep
the intake temperature steady.
Any reasonable person might see that the benifits of a CAI or SRI might
be increased by disconnecting this "Heater" for the Summer months. I
have asked around and researched it and I think that it could be the
magic Holy Grail. Free Mod. This one costs nothing. I think the gains could
be totaly in your head, but what's the point in spending $200.00+ for cold
air if it's going to be heated up in the throttle body? The procedure is
rather simple.
Loop where the coolant leaves to go to the throttle body back to where it
gets returned. Ok H8trs, have at it, I know it seems like a stupid thing to post,
but... I'm not hooking mine up ever again, for what's it's worth.
I PMed "The Man" on the Toronto board, he said that it's only really usefull
in the winter to stop it from freezing and that there would be minimal
gains with removing it. Every bit helps...No?
is heated by coolant. I'm thinking that this is for the winter and to keep
the intake temperature steady.
Any reasonable person might see that the benifits of a CAI or SRI might
be increased by disconnecting this "Heater" for the Summer months. I
have asked around and researched it and I think that it could be the
magic Holy Grail. Free Mod. This one costs nothing. I think the gains could
be totaly in your head, but what's the point in spending $200.00+ for cold
air if it's going to be heated up in the throttle body? The procedure is
rather simple.
Loop where the coolant leaves to go to the throttle body back to where it
gets returned. Ok H8trs, have at it, I know it seems like a stupid thing to post,
but... I'm not hooking mine up ever again, for what's it's worth.
I PMed "The Man" on the Toronto board, he said that it's only really usefull
in the winter to stop it from freezing and that there would be minimal
gains with removing it. Every bit helps...No?
Last edited:
I got a quick question. The line that goes to the throttle body, this is just a parallel path to the rest of the coolant, and no other parts of the engine are in line with this, or are they?
The reason I ask is I noticed yesterday I had a bracket that had been screwed down over this line, and was pinching it enough that I don't think anything was flowing through it. I already had the throttle body coolant bypassed, but I'm wondering if blocking this line could hurt anything.
Can the ends of the lines be capped off instead of connecting the loop. I'm thinking some sweet weight savings on that extra tubing, lol. But seriously, I'm just wondering if having this clamped shut was hurting any other part of my engine.
I saw where it comes from some block on the side of the engine, but I didn't see where the other end of the line goes to(it was hella dark).
The reason I ask is I noticed yesterday I had a bracket that had been screwed down over this line, and was pinching it enough that I don't think anything was flowing through it. I already had the throttle body coolant bypassed, but I'm wondering if blocking this line could hurt anything.
Can the ends of the lines be capped off instead of connecting the loop. I'm thinking some sweet weight savings on that extra tubing, lol. But seriously, I'm just wondering if having this clamped shut was hurting any other part of my engine.
I saw where it comes from some block on the side of the engine, but I didn't see where the other end of the line goes to(it was hella dark).
- :
- MP5T / 944
Bump!
flat_black
Member
Yes, it's just parallel. All it does is run pressurized coolant from the coolant block, up to the throttle body, and return it to the same place, basically. I ran a section of hose from one outlet to the other, without running it to the throttle body.
- :
- MP5T / 944
Good for keping ice from building up in the TB, but for summer stuff..
