Anybody else bypass coolant lines to throttle body?

[92tsifwd]

Anyone else do it?

 

[dsmturboawd]

why would you want to do this?

 

[spoolinawddsm]

its a honda trick, they bypass them so the tb doesnt heat up as fast.

 

[1fast97gsx]

yea I did it ... haven't started the car up yet tho

 

[yo2001]

I bypassed mine, was too lazy to replace the original hose. I'm in AL. though, never gets cold

 

[lowavenger96]

I am running a 90 6 bolt n/t block and used the tb feed lines for the turbo . Never hooked up the tb linesshe runs great.

 

[kpt4321]

Don't bother doing it. You might cool the intake air down a couple degrees, but not enough to make much of a difference.

You will, on the other hand, completely screw up the car's idle speeds. It will think it always is cold, and idle high all the time.

 

[dsmturboawd]

Originally posted by kpt4321
Don't bother doing it. You might cool the intake air down a couple degrees, but not enough to make much of a difference.

You will, on the other hand, completely screw up the car's idle speeds. It will think it always is cold, and idle high all the time.

laf, thats what i was trying to get at. this mod is as dumb as the egr block off. i just dont get it.

 

[clownface]

Originally posted by dsmturboawd
laf, thats what i was trying to get at. this mod is as dumb as the egr block off. i just dont get it.

Well ive done both of those mods and have no problems with idle or anything, my idle was high when i put the car back together but a simple tightening of the BISS fixed that and i cant say for sure that the TB bypass made it jump up. i only did it though cause i had everything out of the engine bay and it only took like 5 min to do both. its prolly not worth wasting a extra bunch of hours of your day to do them but if its there go for it.

If you do the EGR block off and clean the Throttle body out, itll stay clean forever along with other things.

 

[DSMJim]

By-passing the coolant to the throttle body is a complete waste of time. Just because you live in a hot climate and don't get any wierd idle problems does not mean this is still a good mod. The coolant running to the FIAV eventually heats up a wax pellet inside of there which blocks the air way which holds your idle up. It's not there to do anything else other than that. It will not heat up your intake anymore, ever put your hand on your intake manifold after a hard run? Yeah it's hot to, so your not benefiting at all. Zippo, zilch, nada.

EGR is exactly the same thing. EGR does not operate under WOT and were not really concerned with part throttle HP. When is the last time you saw somebody dyno their car at 50% throttle and report the HP? Never because nobody cares. The EGR brings down your EGT during normal driving and also increases your gas mileage. EGR is after your throttle body so it does not contribute to your throttle body being dirty, that is the PCV going back into your intake that does that. When were driving normally good gas mileage is a nice thing. Also why are we concerned with having the inside of our intake manifolds clean? Are you being judged at a show on it? What is left is just carbon and it does not effect the performance of your car one little bit.

Basically these are both complete wastes of time, don't bother with either of them.

 

[yo2001]

Originally posted by DSMJim
EGR is exactly the same thing. EGR does not operate under WOT and were not really concerned with part throttle HP. When is the last time you saw somebody dyno their car at 50% throttle and report the HP? Never because nobody cares. The EGR brings down your EGT during normal driving and also increases your gas mileage. EGR is after your throttle body so it does not contribute to your throttle body being dirty, that is the PCV going back into your intake that does that. When were driving normally good gas mileage is a nice thing. Also why are we concerned with having the inside of our intake manifolds clean? Are you being judged at a show on it? What is left is just carbon and it does not effect the performance of your car one little bit.

but partial throttle is more important for a street car isn't it?

 

[joeym4130]

I bypassed mine, but not for fun
I had a high idle problem, did EVERYTHING to get rid of it and suspected the FIAV. So i got rid of the lines, opened up the 2 halves of the TB and put a gasket over the FIAV outlet. Then my idle was once again brought back down to normal.... Only shitty thing about it is i have to ride the gas until the car gets to normal temps when its cold out (and spring isnt here yet haha). But yeah, i only did it for idle purpose and dont see why otherwise would be a good reason.

I thought the reason guys blocked the EGR was that it goes bad and creates surge or something?

 

[kpt4321]

Originally posted by joeym4130
I thought the reason guys blocked the EGR was that it goes bad and creates surge or something?

I blocked mine so that I could remove more crap that I didn't need from the engine bay. It's as simple as that.

 

[yo2001]

speaking of EGR, would it leak at idle if I just have the valve there in place without any hoke hooked up to it?

 

[VEE-DUBBER]

my car had a funny idle. removed the lines to the TB and i got idle surge. opened it up and blocked off the FIAV and now my car idles so good it's unbelievable ....that a dsm can idle like this cleans up the engine bay too

 

[DSMJim]

Originally posted by VEE-DUBBER
my car had a funny idle. removed the lines to the TB and i got idle surge. opened it up and blocked off the FIAV and now my car idles so good it's unbelievable ....that a dsm can idle like this cleans up the engine bay too

BINGO.. If you pull it off and make a plate for it so that air will not leak its solves the problem. Only thing is you don't get a raised idle when you first start it up and in some colder climates in the colder months before you park the car for the winter in say Oct Nov you have to baby the throttle when you first start it, but thats pretty well it.

Also the EGR removal does clean up the engine bay a whole lot which is about the only good reason to pull it out.

Originally posted by yo2001
but partial throttle is more important for a street car isn't it?

Part throttle is when your trying to get good gas mileage and driving around normally. If your EGR is hooked up you will get better gas mileage so part throttle when your driving normally is very important which is why leaving it hooked up is a good idea.

When your trying to go fast, your at wide open throttle because that's how you go fast! When your at WOT the EGR is shut and not hurting your performance at all, so no worries there either.

 

[clownface]

so how many mpg am i losing??? i already knew i woud lose alittle but if im losing a bunch ill hook that thing back on, anyone?

 

[crankbender]

I am going to have to disagree with some of the things said here. Not flaming just disagreeing.

I have blocked the EGR off on several cars and never had any loss in MPG. maybe 1-2 which is basically unnoticable. However common sense says that the exhaust gas has to be recirculated back before the runners into the main plenum. If this is not done a good mix through all cylinders will not happen and can cause lean/rich conditions. Because of this it DOES dirty the intake. The buildup of carbon robs the engine of more MPG than it will ever save.

As for the coolant lines to the intake on the DSM the throttle body itself is not heated so you are not heating the intake charge much. Putting on an insulating spacer will help more because the aluminum is conducting heat from the head.

 

[92tsifwd]

I blocked off my egr and bypased my coolant lines to tb and noticed no change in gas milage at all. It still idles really clean. Also I plan to make a spacer for the tb & inlet. I bought a 1/2 inch gasket at a local auto parts store for like 5 bucks and that is how I plan to make my spacers. Anybody else try this?

 

[dsmturboawd]

sounds pointless to me.

 

[DSMJim]

Originally posted by dsmturboawd
sounds pointless to me.

This is pretty well the point were all trying to make, it is pointless. Blocking off the EGR does not give HP and only changes the mileage by 1-2 which is next to nothing, however still something albit small. The coolant lines doens't change the heat of the throttle body at all so again is completly pointless.

Basically both these mods are pointless so why bother?

On that note I'm going to re-paint my intercooler pipes white instead of black because white doesn't conduct as much heat a black does so that will definately make my intercooler pipes cooler thus giving me 10-15whp at least...

 

[modifyer]

Originally posted by DSMJim
By-passing the coolant to the throttle body is a complete waste of time. Just because you live in a hot climate and don't get any wierd idle problems does not mean this is still a good mod. The coolant running to the FIAV eventually heats up a wax pellet inside of there which blocks the air way which holds your idle up. It's not there to do anything else other than that. It will not heat up your intake anymore, ever put your hand on your intake manifold after a hard run? Yeah it's hot to, so your not benefiting at all. Zippo, zilch, nada.

EGR is exactly the same thing. EGR does not operate under WOT and were not really concerned with part throttle HP. When is the last time you saw somebody dyno their car at 50% throttle and report the HP? Never because nobody cares. The EGR brings down your EGT during normal driving and also increases your gas mileage. EGR is after your throttle body so it does not contribute to your throttle body being dirty, that is the PCV going back into your intake that does that. When were driving normally good gas mileage is a nice thing. Also why are we concerned with having the inside of our intake manifolds clean? Are you being judged at a show on it? What is left is just carbon and it does not effect the performance of your car one little bit.

Basically these are both complete wastes of time, don't bother with either of them.

I agree with everything except I cannot grasp how introducing unburnt hydrocarbons and CO into the intake increases fuel economy . Exhaust gas in the intake is contaminating the fresh air there is no way that can help mileage , as it cools the exhaust temps it reduces efficiency therefore fuel ecomony has to suffer at least to a small degree .

 

[DSMJim]

Originally posted by modifyer
I agree with everything except I cannot grasp how introducing unburnt hydrocarbons and CO into the intake increases fuel economy . Exhaust gas in the intake is contaminating the fresh air there is no way that can help mileage , as it cools the exhaust temps it reduces efficiency therefore fuel ecomony has to suffer at least to a small degree .

EGR is considered a `metered intake leak' and was developed to reduce the combustion temperatures to below 2,500 degrees, the threshold where NOx is created. Not unlike putting a brick in your toilet to lower the volume of water used, the EGR valve meters a readily available inert gas (actually exhaust gas which contains a lot of very inert Carbon Dioxide) into the combustion chamber to effectively reduce the volume. Smaller effective displacement means less fire, and less heat and thus lower temperatures, thereby controlling NOx emissions.

Obviously we don't want to `reduce' the volume of the combustion chambers (effectively reduced engine displacement) during hard acceleration, so EGR is turned off when you need full power (WOT (Wide Open throttle) conditions). At idle, the engine is very sensitive to air/fuel mixture ratios and swirl in the combustion chamber, so introducing EGR at idle is not on either. However at cruise the Fuel/Air mixture is set as lean as possible for maximum economy and this in turn generates the highest temperatures, and so the EGR uses these conditions to inject exhaust gas into the intake manifold to reduce emissions.

 

[modifyer]

Jim, No problem with how it works of why it was developed in the first place . I agree on all of that .The purpose is to reduce egt's at part throttle by diluting the mixture of fuel and fresh air in the intake causing a less efficient burn hence reducing the Oxides of nitrogen emissions that are a product of extremely high combustion temperatures . At part throttle there is less load on the engine so there is no need to overfuel to reduce heat as there is under full load conditions or during idle to enhance driveability . That is why combustion temps reach the highest levels during this time producing the highest NoX under these highly fuel efficient {lean} conditions conditions . Everything that I have read from SAE and other studies supports the fact that by using erg for this purpose reduces overall efficiency in order to overcome the high temps and reduce NoX . We are adding preburnt gases to an otherwise clean air environment . If efficiency of combustion is reduced then it only stands to reason fuel economy will be reduced not enhanced . This is very evident when monitoring egt's while driving {not tuning at full power}The temps are low until mid range and then drop off again at full throttle , I am talking about an untuned vehicle not something You are manipulatiing with a fuel controller . If You disconnect the egr the midrange temps should go even higher and do in most cases . High temps = better efficiency which should equate to better economy ??
Randy

 

[DSMJim]

Originally posted by modifyer
If You disconnect the egr the midrange temps should go even higher and do in most cases . High temps = better efficiency which should equate to better economy ??

Thats the theory. I don't know enough that I can clearly explain how and why it works. I just know from what I have done and the courses I have been on that EGR is "supposed" to give better economy. I have yet to test my own car out to see if this happens or not. If anything it's going to be a negligable difference. We both agree that it reduced NOx which is the primary function. After that I don't know a whole lot more, nor do I really see fit to study EGR to death either..