Jotun Posted January 14, 2009 Share Posted January 14, 2009 In order to understand a bit more about the technical aspects of my car I've been reading the car bibles and came across something about throttle body heating affecting cold air intakes which I found interesting as I have a K&N typhoon CAI. I was wondering if anyone knew anything about whether the Zed had throttle body heating and if anyone has bypassed this as described below Cold air induction kits work pretty well but you need to do your homework first. A lot of cars have throttle body heaters, whereby coolant from the engine is circulated around the throttle body casing. The idea is to warm up the throttle body to prevent icing in cold weather. The problem is that these systems are hard-wired and don't take account of external air temperature, so even in the heat of summer, hot coolant is routed around the throttle body. This is a problem for CAI kits because you've gone to all the trouble of putting a nice kit in to suck cooler air into the engine, but at the final hurdle it runs through a 75°C throttle body which heats it up again, negating the whole point of the CAI kit in the first place. The solution to this is a throttle body heater bypass, which essentially involves pulling the coolant hoses off either side of the throttle body and patching them together with a length of copper pipe and two hose clamps. When you do this, the throttle body stays at ambient temperature and the CAI kit gets a chance to do its job. The only downside to this is if you live in a cold, humid climate, you might suffer from icing in the winter. But hey - if you do, reconnect the coolant hoses for the winter... Quote Link to comment Share on other sites More sharing options...
Stew Posted January 14, 2009 Share Posted January 14, 2009 I don't think there is coolant pumped around it. There could be some kind of electrical heating. On the side of the throttle body there is what looks like a heatsink however I assumed this was to disipate head away from it. Maybe someone that knows can shed some light on it. Quote Link to comment Share on other sites More sharing options...
3FIDDYZ Posted January 14, 2009 Share Posted January 14, 2009 There is a tube and some wires that goes into the TB... So maybe it does Worth having a poke around though to see... Quote Link to comment Share on other sites More sharing options...
3FIDDYZ Posted January 14, 2009 Share Posted January 14, 2009 What stew said!!!! Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 14, 2009 Share Posted January 14, 2009 I remember the MotorDyne plenum spacer install mentioned something about a heater bypass valve. Not sure if its for the plenum or TB, might be worth a seach on their site. Quote Link to comment Share on other sites More sharing options...
Jotun Posted January 14, 2009 Author Share Posted January 14, 2009 I remember the MotorDyne plenum spacer install mentioned something about a heater bypass valve. Not sure if its for the plenum or TB, might be worth a seach on their site. I came across something similar on a page for the skunk 2 plenum spacer saying that it comes with "the hardware needed to bypass the water lines that heat the throttle body." Does this ring any bells for anyone who has installed a plenum spacer? Quote Link to comment Share on other sites More sharing options...
Stew Posted January 14, 2009 Share Posted January 14, 2009 Oh I seem to remember some pipes and fittinfs when doing my plenum...... Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 14, 2009 Share Posted January 14, 2009 I remember the MotorDyne plenum spacer install mentioned something about a heater bypass valve. Not sure if its for the plenum or TB, might be worth a seach on their site. I came across something similar on a page for the skunk 2 plenum spacer saying that it comes with "the hardware needed to bypass the water lines that heat the throttle body." Does this ring any bells for anyone who has installed a plenum spacer? I didnt have the valve installed when it was done at Phils, so dont know if it was for the TB or not, sorry Quote Link to comment Share on other sites More sharing options...
Adam@Z1auto.com Posted January 16, 2009 Share Posted January 16, 2009 There are 2 coolant hoses that do in fact route antifreeze around the throttle body. The purpose is so that during sub freezing temperatures, the throttle blade does not stick. They are at the bottom part of the throttle body assembly (quite small diameter hoses too...so it's not the massive rush of antifreeze the blurb would lead you to believe. You can bypass the lines if you want, but it will do absolutely zero for performance Whomever wrote that little blurb has obviously decided to regurgitate something they heard, vs taking their time to actually datalog the car themselves. Such is the problem with many posts out there. No content, just conjecture. The throttle body is never at ambient temperature....ever (well, perhaps with the car stone cold and the engine not running it is at ambient lolol). In addition, everything in the engine is aluminum. Aluminum absorbs heat at a rapid pace. Drive your car for even a few minutes and then touch the lower plenum - it will create a blister, that is how hot it gets. So, short of ceramic coating everything in the engine bay to insulate it, you're not going to improve things by more than a small fraction. Even if you were to go that far, the air is moving, it's not sitting still in the intake. As such, if you were to take the differential temperature of the air reaching the plenum vs the temperature of the air being passed through the mass air sensor (where the air inlet temp sensor is found), the difference is not at all substantial. I know this because I spent a substantial amount of time with a rather sophisticated multichannel datalogger when working on the design of my ITB setup, taking the measurements of air temperature at a variety of places, simultaneously Quote Link to comment Share on other sites More sharing options...
Stew Posted January 16, 2009 Share Posted January 16, 2009 Great post Adam. Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 16, 2009 Share Posted January 16, 2009 Great post Adam. +1 As you say Adam, theres so much rubbish on the net, its good to have someone we trust to back up these things as either being true or not. The reason I never fitted the valve was having to remember to turn it on again if it got cold. I would no doubt have forgotten and possibly done damage to my engine, and for what? Well as it turns out now, nothing! Quote Link to comment Share on other sites More sharing options...
IanS16 Posted January 16, 2009 Share Posted January 16, 2009 There are 2 coolant hoses that do in fact route antifreeze around the throttle body. The purpose is so that during sub freezing temperatures, the throttle blade does not stick. They are at the bottom part of the throttle body assembly (quite small diameter hoses too...so it's not the massive rush of antifreeze the blurb would lead you to believe. You can bypass the lines if you want, but it will do absolutely zero for performance Whomever wrote that little blurb has obviously decided to regurgitate something they heard, vs taking their time to actually datalog the car themselves. Such is the problem with many posts out there. No content, just conjecture. The throttle body is never at ambient temperature....ever (well, perhaps with the car stone cold and the engine not running it is at ambient lolol). In addition, everything in the engine is aluminum. Aluminum absorbs heat at a rapid pace. Driver your car for even a few minutes and then touch the lower plenum - it will create a blister, that is how hot it gets. So, short of ceramic coating everything in the engine bay to insulate it, you're not going to improve things by more than a small fraction. Even if you were to go that far, the air is moving, it's not sitting still in the intake. As such, if you were to take the differential temperature of the air reaching the plenum vs the temperature of the air being passed through the mass air sensor (where the air inlet temp sensor is found), the difference is not at all substantial. I know this because I spent a substantial amount of time with a rather sophisticated multichannel datalogger when working on the design of my ITB setup, taking the measurements of air temperature at a variety of places, simultaneously +1 (been dying to do that ) Quote Link to comment Share on other sites More sharing options...
Jotun Posted January 16, 2009 Author Share Posted January 16, 2009 Thanks for that answer I was thinking that it sounded a bit fishy. The web page it was off ( http://www.carbibles.com ) does seem fairly good in terms of knowledge but I thought I'd check it with others as there are a lot of myths and misinformation bouncing around the internet. Quote Link to comment Share on other sites More sharing options...
M13KYF Posted January 16, 2009 Share Posted January 16, 2009 nice post Adam Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted January 16, 2009 Share Posted January 16, 2009 Hi Adam, It looks like the USA plenums and throttle bodies may be different from the U.K. The U.K.throttle bodies do not have any coolant running round them. The coolant is directed to the plenum, very close to where the throttle body fixes to the plenum and in effect heats that part of the plenum and the heat then radiates from the plenum to the throttle body. Same principles apply of course. Alex. Quote Link to comment Share on other sites More sharing options...
Adam@Z1auto.com Posted January 16, 2009 Share Posted January 16, 2009 Hi Adam, It looks like the USA plenums and throttle bodies may be different from the U.K. The U.K.throttle bodies do not have any coolant running round them. The coolant is directed to the plenum, very close to where the throttle body fixes to the plenum and in effect heats that part of the plenum and the heat then radiates from the plenum to the throttle body. Same principles apply of course. Alex. sounds exactly the same - Id have to look on my car to see where exactly the little metal connectors for the coolant go from. it's either on the bottom of the body or the bottom of the plenum at the outlet to the throttle body Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted January 16, 2009 Share Posted January 16, 2009 Hi Adam, It looks like the USA plenums and throttle bodies may be different from the U.K. The U.K.throttle bodies do not have any coolant running round them. The coolant is directed to the plenum, very close to where the throttle body fixes to the plenum and in effect heats that part of the plenum and the heat then radiates from the plenum to the throttle body. Same principles apply of course. Alex. sounds exactly the same - Id have to look on my car to see where exactly the little metal connectors for the coolant go from. it's either on the bottom of the body or the bottom of the plenum at the outlet to the throttle body I think that you will find that it is the latter.......... Quote Link to comment Share on other sites More sharing options...
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