MINI COOPER :: North American Motoring - Project "Low IAT"-Intake Manifold Cooling

Partsman · #1 05-12-2007, 09:12 PM

I've been kicking this project back and forth with DrPhil about how to lower the IATs that we have measured with a ScanGauge II.
We both agreed that if the manifold was exposed to some of the air coming through the grille, that would help to dissipate the heat that would normally soak into the manifold.
While aluminum is pretty good at dissipating heat, the intake manifold is pretty much getting cooked with the supercharger and water pump directly underneath it, and the upper radiator hose running right in front of it. Not to mention the heat transfer from the cylinder head.
I think DrPhil said it best with this statement,
"All the work we've done to cool the air intake with CAIs and fancy ICs is being undone at the manifold just before the air enters the cylinders."

I was looking at the top of the radiator shroud where the hood seal is, trying to see if there was a way to trim it to allow more air in to the front of the manifold. There is really no "nice" way to do it, so I decided to trim it all off...

...as you can see, the radiator hose runs right in front of the manifold, pretty much pre-heating the air coming through the grille.
While I did see quite an improvement in the IATs, as well as very quick recovery after getting off the boost, I had to do something about the hose placement/routing.
So I backed off the two clamps in the pic as well as the one at the radiator, and rotated the hose down away from the front of the manifold...

...the plexiglass(clear acrylic?) is experimental, but I needed to put something there to keep the hose from rubbing on the manifold. It was easy to cut and drill so I could fit it and rivet it to the shroud. The next piece will obviously not be riveted so I can get to the bleeder if I need to.
I have had no difference in coolant temp running the hose this way.

After all this, I am now seeing consistant single digit differences between ambient and IAT while cruising on the highway, sometimes as low as 5 degrees.
Another bonus is getting more air in from the front helps push the hot air out the back.

I realize this is not for everybody, so take it as you will.

Please disregard the rusted bolts on the DFIC diverter, they are NOT the ones that M7 supplies, and will be replaced.

EDIT:
The revised version...

EDIT: The revised version 2...

EDIT: The revised version 3...

jhiggs26 · #2 05-12-2007, 09:22 PM

Good thinking! This could be worthwhile mod for those of us with stock intercoolers!

Jeremy

**DrPhilGandini** · #3 05-12-2007, 09:23 PM

Thanks for sharing this with NAM, Partsman! Yes, it is somewhat extreme, but certainly in the spirit of experimenting, backed up bydata from your temperature probes and SG-II.
I am going to do this also, beginning with moving the radiator hose down, then getting some of that ample air coming in the grille to massage the manifold.
Props to you!

Partsman · #4 05-12-2007, 09:39 PM

Quote:

Originally Posted by jhiggs26

Good thinking! This could be worthwhile mod for those of us with stock intercoolers!

Jeremy

Thanks Jeremy, this would definitely help to flush out the hot air coming through the bottom of the stock IC.

Quote:

Originally Posted by DrPhilGandini

Thanks for sharing this with NAM, Partsman! Yes, it is somewhat extreme, but certainly in the spirit of experimenting, backed up bydata from your temperature probes and SG-II.
I am going to do this also, beginning with moving the radiator hose down, then getting some of that ample air coming in the grille to massage the manifold.
Props to you!

You were a big part of this experiment as well, so thanks to you too.

The shroud is still in a rather "rough" state, I will be smoothing it out so that it looks factory.

Another thing I forgot to mention, is that I should have some kind of heat barrier in between the manifold and the SC outlet. It's pretty tight right there so that will require a little more thought. I wonder how thin you can get Aerogel...

Paul Webster · #5 05-12-2007, 10:55 PM

We've done this as well but I haven't back to back tested like your goodself but I'm glad to see you have some datas for it saying it works.

I have to be honest and say I nicked the idea of Hubie from the M600.

El_Griton · #6 05-12-2007, 10:57 PM

dusts off dremel, ok where do i cut it..........and did you just grab a pre bent hose or did you cut the stock ones?

M7 · #7 05-12-2007, 10:57 PM

Thank you for the spirit of thinking outside the box....

I will talk to my engineer to see if we can produce a thin enough membrane that will do what Partsman is thinking
of.

Peter
M7 Tuning
562-608-8123

Alex5 · #8 05-13-2007, 03:42 AM

Would it be possible to replace a section of the top rad hose to give it a different path? ie a hose with a different bend pattern? Or how about diverting off some of the air that comes through the front grill inlet to the airbox so that it flows over the inlet manifold?
I was also wondering if lagging that offending part of the top hose would help with heat radiation?

Fisher · #9 05-13-2007, 04:52 AM

If you put the manifold down and weld on it some cooling ribbed thing it would be even better.

NMgokart · #10 05-13-2007, 05:06 AM

What about some sort of thermal barrier (either coating or wrap) for the manifold?

**DrPhilGandini** · #11 05-13-2007, 05:36 AM

Quote:

Originally Posted by 3cocinas

What about some sort of thermal barrier (either coating or wrap) for the manifold?

A good question. Insulation is a double-edged sword: it keeps heat out, but it also slows heat dissipation. I'd think that once a nice source of cooling air is found then the manifold should be un-insulated to allow for maximum heat dissipation. To be honest the only place I have a lot of insulation is the air box, since there is considerable heat transfer into the box especially in traffic and stop-start driving.
Partsman's mod reminds us to think air flow, always a good idea!

NMgokart · #12 05-13-2007, 06:19 AM

Got it, Phil. Just early morning pondering. Maybe the cooling fins might work, given the additional airflow?
I seem to be going the opposite direction; after a 250 mile run yesterday, the underhood temps were extremely high. The outlet horn was too hot to touch!
I really need to get a Scangauge to monitor this stuff.

Partsman · #13 05-13-2007, 07:06 AM

Quote:

Originally Posted by M7

Thank you for the spirit of thinking outside the box....

I will talk to my engineer to see if we can produce a thin enough membrane that will do what Partsman is thinking
of.

Peter
M7 Tuning
562-608-8123

That would be great, thanks Peter.

Quote:

Originally Posted by Paul Webster

We've done this as well but I haven't back to back tested like your goodself but I'm glad to see you have some datas for it saying it works.

I have to be honest and say I nicked the idea of Hubie from the M600.

Now that you mention it, I do remember seeing the M600 with a modified shroud, pretty cool.

Quote:

Originally Posted by El_Griton

dusts off dremel, ok where do i cut it..........and did you just grab a pre bent hose or did you cut the stock ones?

Just follow the line of the flat part of the shroud, the stock hose will work fine without cutting.

Quote:

Originally Posted by Alex5

Would it be possible to replace a section of the top rad hose to give it a different path? ie a hose with a different bend pattern? Or how about diverting off some of the air that comes through the front grill inlet to the airbox so that it flows over the inlet manifold?
I was also wondering if lagging that offending part of the top hose would help with heat radiation?

There isn't a lot of room in that area to route the hose a different way. The stock one is actually bent the right way, just needs to be rotated.

TonyB · #14 05-13-2007, 09:53 AM

An Aerogel sleeve to go around the coolant hose would be nice, and if not all the way around, draped over it for a sufficient length should work well. Nice work with the hose rotation!

I echo Dr. Phil's concerns regarding the significance of airflow. This is actually the reason why I have not yet cut-up or trimmed the shroud (as seen above). It seals against the top of the closed bonnet, and in doing so, while in forward motion, creates increased positive pressure forward the exchangers (A/C & radiator), funneling this ambient air through them, thus lowering the temp of coolant, and with that the oil. Air will take the path of least resistance, and if this (the shroud) is not in place, more air will go up and over these (exchangers), not through them...

Along these lines, when I removed my bonnet liner, I knew this would make for a slightly worse seal in this area (less pressure due to escape), and added a thin layer of weather stripping to account for this difference in thickness (not much). The APD (M7 product) shown at the bottom of a couple of the above photos works on the same premise, but for the lower section. This all said, I too will remove this shroud as well, but I will want to fabricate an APD-like contraption / diverter to aid in the channeling of ambient air through the radiator. The only reason I have not yet done this (should be easy) is that I'm looking to ditch my A/C system first, and I'm still doing my homework on this surgery...

**DrPhilGandini** · #15 05-13-2007, 01:32 PM

I just got back from a track day here in Albuquerque (a great MINI course: 1.6mi, 15 corners!)
I removed the shroud before heading out this AM but didn't have time to move the radiator hose (btw, much easier when warm rather than cold!). I need to fab an APD for above the radiator that holds the hose in place and separates the hose from the airflow.
wrt airflow, there didn't seem to be a problem with air being robbed from the radiator as engine water temps never exceeded 207F with an ambient of 80F. While lapping IATs were around 100-110F and airbox temps never more than +2F over ambient (I love my FAD!--maybe it's no longer just a fad...)

Q: what's under that protrusion at the back of the radiator shroud in the middle--I'm guessing a probe or sensor? Can we remove the protrusion?
Anyway, I had a great day as one of the multi-year local racers sat in the passenger seat and got 10seconds of my time (to 1'48"). I still have a long way to go, nut-behind-the-wheel wise, but the car went well.

btw, the M7 COs worked very well!

El_Griton · #16 05-13-2007, 02:37 PM

i'll be cuttin mine asap. But I'm going to keep the cold air intake pick up, and cut the rest off. how thick was that plexiglass sheet, and where did you pick it up at. I was thinking a pet store would have fish tank parts and do-dads

**DrPhilGandini** · #17 05-13-2007, 03:55 PM

I left the air duct intake on the RHS above the radiator. I'll post a picture tomorrow. I would not use plexiglas or acrylic--it gets pretty hot in there and a lot of that plastic is thermally sensitive. I'm going to use mid-guage Al sheet.

Partsman · #18 05-13-2007, 06:11 PM

Quote:

Originally Posted by TonyB

An Aerogel sleeve to go around the coolant hose would be nice, and if not all the way around, draped over it for a sufficient length should work well. Nice work with the hose rotation!

I echo Dr. Phil's concerns regarding the significance of airflow. This is actually the reason why I have not yet cut-up or trimmed the shroud (as seen above). It seals against the top of the closed bonnet, and in doing so, while in forward motion, creates increased positive pressure forward the exchangers (A/C & radiator), funneling this ambient air through them, thus lowering the temp of coolant, and with that the oil. Air will take the path of least resistance, and if this (the shroud) is not in place, more air will go up and over these (exchangers), not through them...

Along these lines, when I removed my bonnet liner, I knew this would make for a slightly worse seal in this area (less pressure due to escape), and added a thin layer of weather stripping to account for this difference in thickness (not much). The APD (M7 product) shown at the bottom of a couple of the above photos works on the same premise, but for the lower section. This all said, I too will remove this shroud as well, but I will want to fabricate an APD-like contraption / diverter to aid in the channeling of ambient air through the radiator. The only reason I have not yet done this (should be easy) is that I'm looking to ditch my A/C system first, and I'm still doing my homework on this surgery...

Tony, I haven't shown an increase in coolant temp at all, but maybe "splitting" the grille will work, basically a flat piece behind one of the slats that extends toward the radiator. I'm sure it will provide you with the flow you want for the radiator, while having some go up to the manifold.

I've also been thinking about removing the A/C.

El_Griton · #19 05-13-2007, 06:21 PM

oh to live somewhere you can even think about taking out the ac. must be lovely.

Partsman · #20 05-13-2007, 06:26 PM

Quote:

Originally Posted by DrPhilGandini

I just got back from a track day here in Albuquerque (a great MINI course: 1.6mi, 15 corners!)
I removed the shroud before heading out this AM but didn't have time to move the radiator hose (btw, much easier when warm rather than cold!). I need to fab an APD for above the radiator that holds the hose in place and separates the hose from the airflow.
wrt airflow, there didn't seem to be a problem with air being robbed from the radiator as engine water temps never exceeded 207F with an ambient of 80F. While lapping IATs were around 100-110F and airbox temps never more than +2F over ambient (I love my FAD!--maybe it's no longer just a fad...)

Nice Phil. Glad your track day was incident free. I wish you had IATs on the track before removing the shroud and then after. It would have been great to see the difference. It's awesome that the FAD keeps your airbox temps so low, that will be the next project.

Quote:

Originally Posted by DrPhilGandini

Q: what's under that protrusion at the back of the radiator shroud in the middle--I'm guessing a probe or sensor? Can we remove the protrusion?

btw, the M7 COs worked very well!

I'm not sure what's behind there, but whatever it is, it's pretty much the same shape as the part of the shroud that covers it. I will look into it more this week.

Partsman · #21 05-13-2007, 06:29 PM

Quote:

Originally Posted by El_Griton

i'll be cuttin mine asap. But I'm going to keep the cold air intake pick up, and cut the rest off. how thick was that plexiglass sheet, and where did you pick it up at. I was thinking a pet store would have fish tank parts and do-dads

The plexiglass sheet is from Home Depot, thay have all different sizes and thickness. I'm going to replace it with some sheet aluminum this week.

TonyB · #22 05-13-2007, 08:37 PM

Quote:

Originally Posted by PARTSMAN

Tony, I haven't shown an increase in coolant temp at all, but maybe "splitting" the grille will work, basically a flat piece behind one of the slats that extends toward the radiator. I'm sure it will provide you with the flow you want for the radiator, while having some go up to the manifold.

I've also been thinking about removing the A/C.

Good to hear (coolant temp not going up). I'm pretty confident that this seal point is for this reason though; and might not truly reveal itself until harsher conditions (much higher ambient temps & track-like abuse) are experienced. Extending a lip forward (JB Weld on aluminum should work well) from the top of the radiator, and on the sides should help capture the oncoming air, and drive it through. The OEM grille has slats angled upward, and I would think that something like M7's will better allow for a more direct shot at the intake manifold...

The only thing keeping me from removing the A/C is that I hear that I will or might get fogging issues in the Winter w/o it. I'm having a hard time getting a solid answer on this, and if true, what's the work-around. That's 23 lbs gone (and off the front!) that I don't need, and allows for better flow through the radiator...

Keep up the great work, I really appreciate it!

04SDmini · #23 05-13-2007, 09:11 PM

[quote=TonyB;1521031]An Aerogel sleeve to go around the coolant hose would be nice, and if not all the way around, draped over it for a sufficient length should work well. Nice work with the hose rotation!

quote]

That's basically what I did, Partially wrapped the hose in thermotec barrier ("C" shaped barrier between the intake and the hose and zip tied the hose in place so there was some space betweent he hose and the intake for air flow. Also did not the self adhesive type Like alot of us have used in the intake box but The kind with the highly reflective barrier).

Partsman · #24 05-13-2007, 09:14 PM

Quote:

Originally Posted by TonyB

Good to hear (coolant temp not going up). I'm pretty confident that this seal point is for this reason though; and might not truly reveal itself until harsher conditions (much higher ambient temps & track-like abuse) are experienced. Extending a lip forward (JB Weld on aluminum should work well) from the top of the radiator, and on the sides should help capture the oncoming air, and drive it through. The OEM grille has slats angled upward, and I would think that something like M7's will better allow for a more direct shot at the intake manifold...

The only thing keeping me from removing the A/C is that I hear that I will or might get fogging issues in the Winter w/o it. I'm having a hard time getting a solid answer on this, and if true, what's the work-around. That's 23 lbs gone (and off the front!) that I don't need, and allows for better flow through the radiator...

Keep up the great work, I really appreciate it!

Thanks Tony.

I'll keep you posted on the coolant temps if summer ever gets here.
An aluminum lip sounds like a good idea as long as it's not too big.

You get winter there?
23 lbs is a pretty good amount of weight off the front, not to mention a more exposed radiator.

TonyB · #25 05-13-2007, 10:24 PM

Quote:

Originally Posted by PARTSMAN

Thanks Tony.

I'll keep you posted on the coolant temps if summer ever gets here.
An aluminum lip sounds like a good idea as long as it's not too big.

You get winter there?
23 lbs is a pretty good amount of weight off the front, not to mention a more exposed radiator.

Winter by your standards, I guess not. In my 10 years in this canyon, I saw snow once, and it lasted less than a day. Internal fogging of glass tends to happen when one gets wet, and then enters a car, especially with a decent temp delta. Fogging of glass sucks, and can be really dangerous... thus my hesitancy...

Thanks for again for the thread!