I had an idea, instead of cutting away the plastic bit at front. Why not make a thin rectangular air diverter to blow on the area between the S/C and intake manifold. That way the thin blanket of air will keep the SC etc. hot air away from the intake manifold? That way you possibly dont need to move the radiator hose?

What do you guys think?

 

you should do some math on air residency times and the like before embarking on this. At anything other than idle (and maybe even then) the air is just ripping through the manifold and only has a few milliseconds of time to contact the Al of the manifold. The measurements indicating lower IATs from the t-MAP sensor are suspect, because the sensor is at the beginning of the log, not at the end. I personally think that the change in reading is due more to cooling the T-MAP sensor than the actual intake charge.

When the car is moving, there is warm post radiator air hitting everything. There may be some value in reducing this, but how much I'm not sure. When the car is at rest, that's when all the hot stuff can just drift upwards to heat things like the IC that results in less than stellar performance when you start moving again.

Matt

 

Mike S: I don't think your diagram is accurate enough in depicting the arrangement of those elements. Your red diverter is actually in the radiator, and the radiator hose is larger and lower than shown. What this means is that even with the IMD mod, the best airflow you will get will be above the supercharger and below the IC diverter (this only works for horizontal flow ICs). As PARTSMAN and I have shown, this directs air at the body of the intake manifold, with most exiting above the manifold and below the IC. I have installed some aerogel material between the supercharger and the manifold to reduce heat transfer. There's really no airflow where you have drawn the red arrow, sorry.
PARTSMAN obtains very good approaches for his car. I presume he is not running the VGS--I get slightly worse approaches and many on NAM have suggested it's due to the VGS. I will be doing some tests on this hypothesis in the next few months as I have to remove the IC to install the new cam, and can install an adjustable VGS mod at that time. (I think someone has already done this, but I can't remember who at present, sorry.)

 

Hi Doc,
Thanks for chiming in. I know I'm not nearly accurate in my MSpaint drawing and I was just trying to remember the positions off the top of my head

So you short your opinion is that this would not be possible? I need to go have a closer look at my car and see what I can get fabricated to keep the air from blowing underneath the intercooler.

 

If you don't move the radiator hose...that will kind of defeat the purpose of trying to cool the intake manifold, because the hose is clamped right to it.

Your idea sounds similar M7's "little scoop"...
https://www.northamericanmotoring.co...tle-scoop.html

Thanks for posting, BTW.


I will be moving the T-MAP to a different location to see if there is any difference in the temps that I get.

 

There has been talk on here about the stock T-MAP being fairly "slow". Anybody have suggestions on what to use to get "real time" IAT readings?

 

My car does not like the VGS...check engine lights both times I hooked it up.

Approaches are usually a 10* difference between ambient and IATs read by the ScanGauge...now with it being really cold, I often see single digit approaches.

 

I have been watching this thread from the beginning, very good info. Thank you to everyone who has contributed . Now it seems there was never really a consensus to what was "best". Partsman, what do you think should be done at the very least to these cars? I am running the stock I/C and don't plan on changing, unless I can find a GP I/C. Do you recommend atleast moving the upper rad. hose? Can you post a order of recommened mods for the IAT project? In a order from what you think "must" be done, to what "might" help. Thanks for any info.

 

Moving the radiator hose will help to a certain extent, but you will still not have any airflow to that area.

For your application, at the very least you could do something similar to what Mike S posted above, if you didn't want to go the route that myself and DrPhil did.
If you do plan to open the shroud to allow for more airflow...be sure to fabricate some sort of block-off plate or at the very least use a piece of weatherstripping to seal the gap between front bottom edge of the IC where it meets the intake manifold. You don't want air forced under the stock IC, as it will disrupt the air coming in from the scoop. If you need help with this, let me know.

I'm not really able to post an "order of mods" for this project, because if you do one(radiator hose) without the other(airflow) or vice versa, you're really not getting the full effect of the mod.
Remember, airflow into the MCS engine compartment is good.

I hope this helps... if you have any more questions, please don't hesitate to ask.

 

Is the hose accessible enough to wrap with heat reflective material? That would keep the hose heat off the intake manifold, but might shorten hose life by not allowing the heat to radiate. Why not put heat reflective material on the intake manifold region adjacent to the hose?

 

This question raises the issue of how heat is generated and transmitted inside the engine bay, both while at rest and while moving. As Dr Obnxs, PARTSMAN and I have always maintained, it's really all about how air moves around under the bonnet. We don't have wind tunnels and the type of resources available to the Audi LeMans race team, so it's mainly intuition and guesswork. Still, experimentation is pretty easy.
The problem is that heat reflective material reduces transmission of heat from outside sources to the object, but it also reduces heat from the object being radiated away. The question then is: is the air and material of the intake manifold hotter, or colder, than the surrounding air and heat sources. The radiator is hot, no doubt, as is the radiator hose. But the air coming in from the grille while moving is pretty close to ambient, which is going to be cooler than either the radiator temp, or the intake manifold temp.
My sense is that wrapping the manifold is not a good idea.

 

Hi Partsman,
That is exactly what I mean. My car is at BMW for it's oil change and other repairs right now that is why I have not been able to get more of an accurate idea Once the car is back I will investigate further. No problem, we're all here to help each other!

 

I have followed this thread closely, but also the one of the HAI some of you also posted on. I love all the ideas but just have anouther take on things. Alot of guys with old handas and toyotas have big hole in front of the car, for "ram air" intakes. doesn't the intake that goes to the air box have the same effect? If so, con't you think that it is possable to use this and a short piece of ducting to get almost the same effect? If not this way then what about getting the air from somewhere else? Just asking cause i know on the old mini some people down here does it [FONT=Calibri][SIZE=3]to prevent fuel evaporation?[/SIZE][/FONT]

I'm all for moving the radiator hose to clear the space around the manifold.

Thanks anyways for all the good info and pics!

 

With the OE IC don't cut or move anything, you DO NOT want air under the IC.

This is the Phoenix of threads. You have 2 of the best, Dr. Phil & Partsman ( the best from 2 different climates ). Dr.Phil needs a new polishing cloth, IMHO.

 

Quite rightly identified as one of the old pheonix-s, Steve!! What's impressive is that there really isn't any new news on this front, other than RMW's water-meth system and the occasional water to air IC threat.

I'm polishing my exhaust system these days (talk about a turd)--yet another straight through system on its way from Juston of CMC. Should get it next week I hope.

 

Thanks Steve...I was surprised to see the thread bumped back up.

Uh-oh ...another system? I do admire the fact that you are sticking with it until you find the perfect setup.

 

not sure why air under intercooler is bad?
would not some flow here assist draw, ie via faster air lower pressure...

 

Yea, I PM'ed Parstman yesterday. Not really much I should do, especially with these wacked out smog shops here in California I was told one guy had to remove his Alta diverter, he was told by the smog man it wasn't stock , thats how insane it is.

There are a couple of guy's watching your staight thru exhaust system thread like hawks here, they have already deleted their battery box's

 

If the air entering from the front(with the mod discussed in this thread) is higher pressure than the air flowing through the stock IC from the scoop, then you will have what I believe they call "shear"...pretty much cutting off the air from the scoop on the bottom of the stock IC. With the stock IC(or any IC for that matter), you don't want anything to disrupt the airflow through it.

 

I wonder if anyone has ever tried to lift the stock IC up? You know, give it more space underneath, for a easier time for the air to be relived. This would involve some hood modification though.

 

No hood modification necessary...
https://www.northamericanmotoring.co...tercooler.html

 

There's a project being discussed over on the Forum boards about putting together stickies on all these oldies but goodies threads. They would be compilations of the main points, with links to the actual posts on the original threads.
I like the idea, but just don't have the time to dedicate to that project as well as all the other things I do (like work...haha)

 

That link is a oldy but a goody, thanks. So you only lifted the rear of the IC correct? Didn't understand about the cutting part? Do the IC boots give enough to allow the larger gap?

 

The boots will not give enough to allow the IC to be tilted...that's where the "cutting part" comes in...

On the ends of the stock IC where the boots clamp to, there is a point where they "become" the end tank. That is where I cut.
To help you visualize, pretend you were going to slice the ends that you clamp the boots to clean off, but about a little more than halfway through the cut you stop, leaving the end still attached to the end tank.
Blow out the metal shavings, slip the IC back into the boots, you are now able to tilt the IC up at the back, have my very good friend who owns Nutmeg Tool tack it in place, remove the IC, and finish welding up the cut area, and there you go...boots are still straight, but the IC is lifted at the back.

 

Wow thats really not to bad to do. With all the stock IC's around I might just try this