Go Back   Team-BHP > Under the Hood > Technical Stuff > DIY - Do it yourself


Reply
 
Thread Tools Search this Thread
Old 12th March 2013, 09:02   #16
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default Re: 2007 Esteem - TB Coolant Bypas

Quote:
Originally Posted by im_srini View Post
When I was trying to source Black-Phenolic-AA grade sheets a few years ago for the intake gasket, I was told that Phenolic-AA material was not made anymore (instead was directed to G-11/FR-5 Epoxy Sheets).
Did you manage to make the insulating gaskets? If yes please share the details, we are now planning to make one for the Esteem.

The ones readily available for the G13B is expensive at $79!!

Quote:
Similar thing here (Strange Behavior of my ALTO, Expert's Advice needed). Surprising that coolant circulation through the throttle-body was present, then removed in later models, & now appears to have been reinstated !?!
Maybe its reinstated for better fuel efficiency and safety reasons to prevent any possible instance of icing.
Sankar is offline   Reply With Quote
Old 12th March 2013, 10:32   #17
Senior - BHPian
 
thoma's Avatar
 
Join Date: Oct 2011
Location: Kerala
Posts: 1,750
Thanked: 1,073 Times
Default Re: DIY : Throttle Body - Coolant bypass

Since I got some time to think over this post, some queries propped up in my mind.

Going by the temperature and temperature difference in the post with the graph, that means a density difference of ~ 0.04 kg/m3. IIRC, the air-fuel ratio calculated by the ECU is by weight than by volume. So that equates to more fuel pumped in to compensate the additional air weight. And thus more power per stroke?

Do we really have a sensor in the car to measure the intake air density? Or is that arrived-at from the exhaust readings?

Quote:
Originally Posted by Sankar View Post
But since an engine runs best with colder air
...
In our climate i see no reason why the TB needs to be warmed up as it doesn't help in performance and it doesn't get anywhere close to freezing here.
Quote:
Originally Posted by Sankar View Post
Yes its done to preheat the air in colder climate and also to prevent the icing of throttle body.
If colder air was better, then why should the manufacturer spent additional resources to heat up the TB? I am sure this is not for cranking purposes as the coolant itself will be cold at the time of cranking. There should be some reason this has been provided. But what exactly? Is it to make the engine more frugal at the cost of power/torque?

Last edited by thoma : 12th March 2013 at 10:40.
thoma is offline   Reply With Quote
Old 12th March 2013, 10:58   #18
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by thoma View Post
Do we really have a sensor in the car to measure the intake air density? Or is that arrived-at from the exhaust readings?
Most of the fuel injected cars I have seen make use of a manifold air pressure sensor to determine the amount of air going into the engine. But the final determination of fuel to be injected is done from the exhaust readings. That is why in stock cars if you connect a air fuel ratio gauge, you will notice that the fuel injection continuously cycles between rich and lean.
vikram_d is online now   (1) Thanks Reply With Quote
Old 12th March 2013, 11:34   #19
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by thoma View Post
Since I got some time to think over this post, some queries propped up in my mind.

Going by the temperature and temperature difference in the post with the graph, that means a density difference of ~ 0.04 kg/m3. IIRC, the air-fuel ratio calculated by the ECU is by weight than by volume. So that equates to more fuel pumped in to compensate the additional air weight. And thus more power per stroke?

Do we really have a sensor in the car to measure the intake air density? Or is that arrived-at from the exhaust readings?
Colder air is denser, denser air exerts more pressure so i believe that a MAP equipped car can compensate for the denser air that flows into the manifold. In my car the IAT sits before the Tbody whereas the MAP sensor is on the manifold. MAP's input is also taken for fueling, O2 sensor is the eye of the ECU since its telling ECU what it sees in the exhaust and how the fueling should be altered to maintain AFR.


Quote:
If colder air was better, then why should the manufacturer spent additional resources to heat up the TB? I am sure this is not for cranking purposes as the coolant itself will be cold at the time of cranking. There should be some reason this has been provided. But what exactly? Is it to make the engine more frugal at the cost of power/torque?
Not all cars have the coolant circulating in the Tbody, my friend's 2007 Esteem doesn't have this and like im_srini said in the post above its not there in his car either. As to reasons why its there its mainly to prevent icing while the car is in use.
Sankar is offline   (1) Thanks Reply With Quote
Old 12th March 2013, 11:36   #20
BHPian
 
dhawcash's Avatar
 
Join Date: Dec 2008
Location: jaipur
Posts: 124
Thanked: 141 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Going by the temperature and temperature difference in the post with the graph, that means a density difference of ~ 0.04 kg/m3. IIRC, the air-fuel ratio calculated by the ECU is by weight than by volume. So that equates to more fuel pumped in to compensate the additional air weight. And thus more power per stroke?

Do we really have a sensor in the car to measure the intake air density? Or is that arrived-at from the exhaust readings?
Most suzuki engines do not have a mass air flow sensor. They rely on intake air temperature sensor and manifold pressure sensors. Not an expert in fluid dynamics, but pressure and temperature are mathematically related to density of air (which in turn can be used to calculate the volume), if some constants are known, and thats how the ECU calculates the amount of air available.Inputs from the lambda sensor also help to keep the mixture slick.
dhawcash is offline   Reply With Quote
Old 12th March 2013, 13:13   #21
Distinguished - BHPian
 
Join Date: Oct 2012
Location: Delhi
Posts: 3,063
Thanked: 6,217 Times
Default Re: DIY : Throttle Body - Coolant bypass

There is of course a reason why the original manufacturer design has the throttle body heated.

In general there are two reasons:

Firstly atomized fuel mixes better with warm air than with cold air. In particluar relevant with carburator engines and the early injection systems where air/fuel were mixed prior to entering the cilinder. In theory you lose a bit of efficiency as you let warm air into the engine. But that is offset by the gain of having a better mixture.

The second reason is still very relevant for all engines: Freezing!!
The airpressure drops after across the throttle body and that means condensation and freezing can occur. Contrary to popular believe the ambient temperature doesnt need to be that low before this happens. It's really a combination of humidity, ambient temperature and air pressure.

So for instance driving in mountains (higher altitude means lower air pressure means earlier condensation) even at ambient temperatures this phenomena is known to occur.

There might be also be a third reason; it keeps the throttle plate clean of carbon deposits. On most cars some of the blow by gasses are re-introduced to the inlet side of the throttle body. Having it heated will prevent the carbon deposits to crystalize on the plate and body, thus preventing built up.

If you ever suffered from a stuck throttle plate you will know what this looks like. Believe me, it does happen, some cars/engines are more prone to it then others.

Each to its own, but I make it a general rule not to mess with something I dont fully understand. Each car might be different, but before I would attempt to "enhance" the design of any component of my car, I would really like to understand why in this case the throttle body was heated and how big the affects could be.

Engineers never do anything by chance. If anything producing an engine with a heated throttle body is more expensive then without. More complicated body to cast/manufacture, extra plumbing etc.

So they must have had a very good reason for designing it the way they did. Lots of post in this thread, but very little understanding about why its heated in the first place. So be aware.

Jeroen

Jeroen
Jeroen is online now   (4) Thanks Reply With Quote
Old 12th March 2013, 16:12   #22
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by Jeroen View Post
There might be also be a third reason; it keeps the throttle plate clean of carbon deposits. On most cars some of the blow by gasses are re-introduced to the inlet side of the throttle body. Having it heated will prevent the carbon deposits to crystalize on the plate and body, thus preventing built up.
In most cars including mine the EGR exhaust gases are almost always introduced after the throttle plate and the throttle body.This is done for the reason to keep the tbody clean, be it heated or not.

But what is introduced before the tbody (in some cars including mine) is crankcase gases by means of PCV valve, these gases may condense in the tbody when the conditions are right, but whether that is a cause of concern for me needs to be tested.

If it does happen then the solution for this is an oil-catch-can.

Quote:
Each to its own, but I make it a general rule not to mess with something I dont fully understand. Each car might be different, but before I would attempt to "enhance" the design of any component of my car, I would really like to understand why in this case the throttle body was heated and how big the affects could be.
When the manufacturer builds a car they do it for the general public and whatever regulations that need to be met. If the tbody coolant was that important then the manufacturer would standardise the presence of it in all of their models.

If someone is of the kind that they believe manufacturer knows the best then its better not to fiddle with their cars. I don't believe that a car rolling out of the factory floor is as perfect as it gets, maybe its the perfect car for the masses but i see everything in it as a compromise.

Quote:
Engineers never do anything by chance. If anything producing an engine with a heated throttle body is more expensive then without. More complicated body to cast/manufacture, extra plumbing etc.

So they must have had a very good reason for designing it the way they did. Lots of post in this thread, but very little understanding about why its heated in the first place. So be aware.

Jeroen

Jeroen
So what explains this?
2007 MPFI Esteem doesn't have coolant running through the tbody but the earlier MPFI Esteem does? Same case with Alto.

And before i embarked on this i did a lot of reading and came across many posts like this which said manufacturer knows the best, and some saying the gains are too little to be noticed. There were also posts from people who have actually done this and found unexpected gains. Depends on the car too!

Last edited by Sankar : 12th March 2013 at 16:14.
Sankar is offline   Reply With Quote
Old 12th March 2013, 16:32   #23
Senior - BHPian
 
thoma's Avatar
 
Join Date: Oct 2011
Location: Kerala
Posts: 1,750
Thanked: 1,073 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by Jeroen View Post
Engineers never do anything by chance. If anything producing an engine with a heated throttle body is more expensive then without. More complicated body to cast/manufacture, extra plumbing etc.
Quote:
Originally Posted by Sankar View Post
When the manufacturer builds a car they do it for the general public and whatever regulations that need to be met. If the tbody coolant was that important then the manufacturer would standardise the presence of it in all of their models.

If someone is of the kind that they believe manufacturer knows the best then its better not to fiddle with their cars. I don't believe that a car rolling out of the factory floor is as perfect as it gets, maybe its the perfect car for the masses but i see everything in it as a compromise.
Aren't there two ways to it? Manufacturers got resources much more than the individuals to try out various combinations and to record them. That does not mean that the enthusiast in us should not try modifying anything. From the start of time, if everybody were running on stock cars, there won't be these much manufacturers themselves.

But if the manufacturer puts and removes a thing from their car, he knows the exact reason for that, even for a compromise. Need not be the case with an individual; on the other hand, if the enthusiast come to know better than the manufacturer, well and good.

I'll term this thread as a good initiative and we may achieve good results; but en route, the real challenge is to get to the bottom of why exactly the manufacturer put in and removed the item.
thoma is offline   Reply With Quote
Old 12th March 2013, 16:45   #24
BHPian
 
im_srini's Avatar
 
Join Date: Sep 2006
Location: Portland
Posts: 956
Thanked: 368 Times
Infractions: 0/1 (5)
Post Throttle-body & IACV : 101

Quote:
Originally Posted by dhawcash View Post
I am working on a suzuki G16B unit ... I noticed ... the coolant pipes running to the throttle body ... the coolant circulates only at a corner of the throttle body ...
Quote:
Originally Posted by im_srini View Post
Yes, you're right, the coolant is circulated through a small chamber at the back of the throttle body & basically serves to heat up the throttle body. Will post pics of the Swift's throttle body.
1st Pic : Swift G13B throttle-body, looking at it from the intake manifold end, & TB's inverted. The IACV has been placed on the TB & the arrows point to where the plumbing for the coolant pipes go in.

Name:  SwiftThrottleBody_00.PNG
Views: 2139
Size:  949.5 KB

2nd Pic : Swift G13B throttle-body, looking at it from the intake manifold end, & TB's inverted. The IACV has been removed & the arrow points to the chamber in the TB where coolant is circulated.

Name:  SwiftThrottleBody_01.PNG
Views: 4188
Size:  802.0 KB

3rd Pic : Swift G13B throttle-body, looking at its underside, the chamber in the TB where coolant is circulated can be seen clearly. As mentioned by Dhawcash the coolant's circulated in a small corner of the TB.

Name:  SwiftThrottleBody_02.PNG
Views: 2098
Size:  901.2 KB

4th Pic : Swift G13B throttle-body, looking at it from the intake manifold end, & TB's inverted. The IACV has been positioned so that air-flow through the TB & IACV can be visualized. The port marked "A" opens upstream of the throttle-butterfly & the port marked "B" opens downstream of the throttle-butterfly. The corresponding ports on the IACV have been marked A' & B'. The passage from A' to B' within the IACV is controlled by a flap which is moved back-&-forth by a servo motor. When idling, i.e. the throttle-butterfly's completely closed, air flows from A -> A' -> IACV -> B' -> B. In essense, the IACV allows a controlled "leak" or "bypass" of air around the closed throttle-butterfly, thus controlling idling speed of the engine.

Name:  SwiftThrottleBody_03.PNG
Views: 4284
Size:  1,010.0 KB

5th Pic : Swift G13B throttle-body, looking at it from the front & TB's right side up. The arrow is pointing to the opening of port "A".

Name:  SwiftThrottleBody_04.PNG
Views: 3254
Size:  868.3 KB

6th Pic : Swift G13B throttle-body, looking at it from the intake manifold end, TB's right side up. The arrow is pointing to where port "B" opens into.

Name:  SwiftThrottleBody_05.PNG
Views: 1816
Size:  904.8 KB

Quote:
Originally Posted by Jeroen View Post
Engineers never do anything by chance. If anything producing an engine with a heated throttle body is more expensive then without. More complicated body to cast/manufacture, extra plumbing etc. So they must have had a very good reason for designing it the way they did. Lots of post in this thread, but very little understanding about why its heated in the first place.
Hi Jeroen, your point is very valid, but why remove it & then put it back in again ?
Is it possible that the removal of the Throttle-body coolant bypass was a failed experiment (?).

Here's some information regarding the "Speed-Density" system used to estimate air-flow.

Last edited by im_srini : 12th March 2013 at 16:55.
im_srini is offline   (3) Thanks Reply With Quote
Old 12th March 2013, 16:48   #25
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by thoma View Post
Aren't there two ways to it? Manufacturers got resources much more than the individuals to try out various combinations and to record them.
Of course they have vast resources, and from posts made by Behram sir on various threads i realised that all that is good fo the car or the enthusiast doesn't always come out in a production vehicle. Often some things are compromised.

Quote:
Originally Posted by im_srini View Post
Is it possible that the removal of the Throttle-body coolant bypass was a failed experiment (?).
What were they experimenting? What results were they expecting?

Last edited by Sankar : 12th March 2013 at 17:05.
Sankar is offline   Reply With Quote
Old 12th March 2013, 17:20   #26
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: DIY : Throttle Body - Coolant bypass

My Swift with the G13B never had any coolant pipes going into the throttle body. Strange to see that it has a provision for it.
vikram_d is online now   (1) Thanks Reply With Quote
Old 12th March 2013, 17:30   #27
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default Re: DIY : Throttle Body - Coolant bypass

The Esteem's tbody too had holes in it like in the pic posted above but there weren't any connectors for the coolant pipes to connect like in the pic below.
DIY : Throttle Body - Coolant bypass-20130306_083044.jpg

Maybe from 2007 Esteem onwards they eliminated this in the G13B engine which also powered the Swift.
Sankar is offline   Reply With Quote
Old 12th March 2013, 17:47   #28
Senior - BHPian
 
thoma's Avatar
 
Join Date: Oct 2011
Location: Kerala
Posts: 1,750
Thanked: 1,073 Times
Default Re: Throttle-body & IACV : 101

Quote:
Originally Posted by im_srini View Post
Swift G13B throttle-body
Nice details with the pictures. Till now, I had only dealt up close with carburetors and this is the first time I see a disassembled throttle body and practically relate to IACV and so on; even though I have a G16B at home for the past 7 years, I never tried to learn further. I was thinking that these were too complex. No, nothing when compared to the sensitive diaphragms and needles in the carburetor. Thanks for the pictures.

Quote:
As mentioned by Dhawcash the coolant's circulated in a small corner of the TB.
So, should we say that the exchange of heat is more useful for idling than at other times?

EDIT: OT: Checked my G16B to have the coolant pipes running from the throttle body (marked red). But it has some additional pipes (marked green) running from the engine head to before and after the butterfly.
Name:  IMG_5038.jpg
Views: 3952
Size:  63.4 KB

Last edited by thoma : 12th March 2013 at 18:15.
thoma is offline   Reply With Quote
Old 12th March 2013, 17:54   #29
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: DIY : Throttle Body - Coolant bypass

Quote:
Originally Posted by Sankar View Post
Maybe from 2007 Esteem onwards they eliminated this in the G13B engine which also powered the Swift.
My car is registered July 2006. So I'm guessing they started this trend with the Swift petrol.
vikram_d is online now   Reply With Quote
Old 12th March 2013, 17:58   #30
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,508 Times
Default

Quote:
Originally Posted by vikram_d View Post

My car is registered July 2006. So I'm guessing they started this trend with the Swift petrol.
Yep, that might be the case. It skipped my mind that Esteem and the Swift coexisted for couple of years.
Sankar is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Throttle body cleaning amit_mechengg Technical Stuff 89 13th August 2016 19:01
Throttle Body Enlargement / Expansion hellspawn Modifications & Accessories 42 1st December 2009 09:44
RPM Surges-Throttle Body Cleaning wolfinstein Technical Stuff 29 6th October 2009 08:12
Throttle Body Bypass 1self Modifications & Accessories 3 7th September 2007 14:31
Optra, Throttle body repair sage Technical Stuff 5 7th June 2007 12:30


All times are GMT +5.5. The time now is 00:57.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks