So I just got done reading the Mini2 post about underhood temps:
http://www.mini2.com/forum/showthread.php?t=42063

And I tried to get some information py posting this, but really wasn't satisfied:
https://www.northamericanmotoring.co...ad.php?t=42403

I took a look at my stock intercooler cover, and found no real reason for it to be on, in fact it looked like there was a possiblity that it was restricting flow to the back 2/3 of the intercooler.



You'll notice that there is a piece of plastic that acts as a diverter about 1/3 of the way up (front to back) on the cover. This piece seems to divert air moving across the intercooler down into the intercooler itself. The problem that I see is that it also deflects air from getting to the back 2/3 of the intercooler itself. Im no expert when it comes to intercooling, so perhaps directing a flow of air into a small part of the intercooler is better than just allowing air to flow over it, but I haven't seen this used on any other top-mount that I can think of.

I took off my cover because I hate excessive plastic in my engine bay, and I would rather look at an intercooler...than an intercooler in a plastic jail. I was told that the cover was necessary, and once again I got the "mini engineers know everything, so it cant be wrong" speech. It just seems like a pointless piece...am I wrong to think so?

-Jake

 

If you remove the plastic cover, the air would then just blow over and around the intercooler. With it all sealed, the air is forced to go between the cooling fins because of preasure from the scoop.

I got the Alta diverter to replace the stock piece, mainly for the spray. I'll be taking all that stuff off soon for a cleaning, I'll try a couple runs without anything covering the IC and see what kind of intake temps I get and report em.

 

Here is another famous top mount w/o any plastics...

 

what's the underside of the hood look like?

The outer edges of that IC are obviousley ready to accept a seal of some kind.

 

The STi hood does have a stock rubber gasket that seals the intercooler. I just got a lesson on top-mounts from an STi owner here at work...cfm, pressure drop, air pressure difference between the bottom of the car and the hood scoop intake pressure etc....very interesting stuff.

I was looking around on NAM, and on the internet (havent checked Mini2 yet) but I didnt really come across any good discussions about the stock intercooler. Nothing about the flow, or the pressure drop...anyone have any info? After listening to my friend I do think the top will make somewhat of a difference, but I think that Im going to make a rubber seal (vs. the foam we have) and keep the plastic off.

Edit: Just checked Mini2 and didnt find any tech. info there. Also something that just dawned on me...none of the aftermarket intercoolers I've seen have any sort of plastic diverter on them...

 

Like this?

 

Actually, I think we could do something like the STi, doesn't look that hard. Maybe just rivet some alum. plates around the outter edge to match stock??? ah, so much to look into.

 

Whoa! Is that what the intercooler looks like with the plastic removed? If so it seems like that about 20% of the intercooler is covered by plastic. Did you stick down that rubber seal around the exposed IC?

Amit

 

Isn't that the ALTA cover?

 

The GRSmotorsports, top-mounted, air-to-air, intercooler does not have a cover; however, there is a diverter that attaches under the front air scoop and channels air to the intercooler. This intercooler from GRS is a very nice unit with about 1 litre extra internal volume.

 

That's Alta sir.

 

The logic behind the stock cover is that the rib that runs across the middle is acting like a scoop inside your scoop. It's job is to equalize the airflow across the intercooler as the flow makes a right hand turn.
When airflow enters "the royal mail slot" it wants to go straight because thats the path of least resistance. It will keep goins straight until it runs into something, where it either has to stop or is redirected down the next path of least resistance, which is down through the intercooler. The problem here is that all the air will want to go through the back of the intercooler because it wants to go straight and it can do that until it hits the seal on the backside.

How do you fix that? You place a half height scoop in the middle of the intercooler to split the flow, forcing the lower half of it to be redirected down the front portion of the intercooler and upper half down the back portion.

When airflow is forced to turn, its a pretty complicated thing. Keeping flow uniform and laminar is really tricky. This is why flow QUALITY is more important than flow QUANTITY.

--
Cheese

 

The subaru crowd calls it a "splitter." and its attached to the hood scoop instead of the intercooler.

 

Thanks Cheese....that perfectly explains the intercooler cover to me I was viewing that mini cowel as more of a total blocker, than a partial blocker. Thanks so much for that great write up.

-Jake

 

The STI intercooler does not have/need the diverter since the scoop is placed on top of the intercooler. So the air will directly hit the intercooler from the top and go between the fins. Unlike our MCS...

 

Maybe we should try and do this..simple thang.

 

That is a larger intercooler by alta, not just the diverter/cover.

 

I've been recently wanting to go the route of the alta larger top mount intercooler. I just bought the M7 hood scoop and thought the intercooler would be a good next step. How do you like it? Is it worth the money?

 

I might go for GRS LArger intercooler...

http://www.grsmotorsport.co.uk/minicoopers.html