I was at Dinan yesterday for MC Squared.... That guy sure knows his stuff! Anyway, when Gary and I were getting the Steve led tour of the facility, we popped the hood of their demo car and he started talking about the CAIs....

1) The stock airbox is air starved due to the small diameter of the tube going into the airbox.

2) He used plastic because of it's insulating properties.

3) The airbox usually runs at a bit of negative pressure, so any hot air gets sucked in. This is significant for all that go topless with CAIs....

4) They use a seal in their CAI to make sure the top and the bottom don't have any leaks.

Any of this sound familiar?

As a perk, we got the test car for the afternoon, and since it was so stinking hot, they gave it to me for the whole weekend to really see how it can perform! It's a very well sorted car.

Matt

 

Get a thermometer and pull some #s for us!

Actually sounds very familiar.

VGB- I have my insulation as such that I experiance the same quieting effects as the rest, but I don't actually touch the filter, I'm hoping but still have no way of testing, that this setup provides me the best of both worlds (or at least a decent comprimise) unfortunately my butt-dyno numed out driving on the stock box for a day.

The next step may be to mount 1 or 2 of those computer power supply cooling fans in the cowl and get them to activate under 5 MPH to keep cool air flowing into the intake; that coupled with the insulation to keep the heat out and hopefully I can get rid of those extra 2 degrees and have a Cold air intake 100% of the time.

 

And Dr. congrats on passing 4k posts

 

Why go power supply(left), when you can go 3U server style(right)?

 

Put this over on the master cylinder side and run hose to the intake side.

 

eRAM, the electronic supercharger! 1000 cfm @ 1 PSI!

How's that for post number 4000!


Matt

 

I LOL'ed

Excellent 4000! Congrats!

 

Cool (pun...)

Ok, I'm readying for a bluegrass festival so have to be brief...

I'll be leaving the thermal pad setup on as seen above for at least the short term. Everyone else's butt dyno (I don't trust mine anymore) seems to report better pickup and they all seem to like the reduced SC sound...

My thoughts are as follows...

1) If I were installing an Alta CAI now, I'd insist on getting with the top, and I'd line the top and inside walls with the flat closed cell insulation before installing it. I'd also somehow put a piece up against the ECU on the left side and I'd figure out a clean way to line the stock airbox bottom. I might even go double thickness and insert a piece of sheet aluminum between the sheets.

2) Knowing what I've seen and felt, I'd be more inclined to get a CAI that is either made of plastic or that has its own insulation. I'd also look very carefully at easy mods to the stock intake that would let it have cold outside air and perhaps a cone filter.

One last thought, then gotta run...

About butt dynos...

If it were just our butts, I'd trust them more about judging throttle response... However, this mod also affects sound in a big way. It is remotely possible that my shifting habits have been somewhat centered around the sound of the SC lately. As such, with that sound changed so radically now, my shifting may have also changed. Sooo, while it definately feels like it pulls harder and the throttle response is crisper, I'm not sure...

If anyone who is doing just thermal mods to the airbox has a baseline and a way of measuring performance, I'd love to see the numbers... Again, on my car, based on my butt and ears together, I'd guess 5, maybe even the 7 to 9 numbers that Randy estimated sometime back. But I don't trust my ears :D .

I'll be out tonight and most of tomorrow, will check back in here after some long drives and lots of music. Maybe my ears will be music-deaf enough then to be more trustworthy :D .

Thanks all!!!

-- VBG

 

When I first went out today for the first 100 or so miles it felt like I had killed the car then everythig came back and I was very happy, I'll ned to go and see if I can find weather reports for earlier in the day as it may have been humidity messing around with things.

Also I was in the dealer geting the car washed and scheduling an appointment for Mon.; while I was in the service area I shut the car off, when they started it up, well I had never heard my MINI sound that good. The resonance of the service bay was wonderful, the insulation seems to be a great balance of sound and functionality IMO.

 

I love the sweet sound of the MINI is the service garage. It just makes it sound HUGE!

In other news...

I think I'm going to wrap my downtube in that duct insulation too. Don't know why I didn't think of that before.

 

I have some more observations, but will wait until tonight after the drive... About 200 miles...

-- VBG

 

Well, I drove most of the day yesterday. It was fun, but lots of driving, I'm glad to be off the road today. My MINI is a mess, I need to give it a bath...

Driving conditions were mixed... Probably 50/50 high-speed/freeway and city/stop-and-go. About 250 miles. Temps outside ranging from the mid-70s to the mid-90s. I'd consider it a pretty good workout... And add to that the previous 2 days driving about 250 mostly high-speed/freeway miles altogether, for about 500 miles this weekend. I think that the thermal pad idea has been tested pretty well...

So, here are some summary observations about my simple thermal pad design...

1) It's been a long, fun weekend and I'm tired of driving.

2) At various locations, various outside temperatures and various times-of-day I've popped the bonnet and tested the temps by hand... Touching the outside of the Alta airbox I literally have to pull away quickly to avoid burns, I'd guess the metal airbox temp is around 140 degrees (f). Each time opening the padding and testing inside, the filter was either cool or barely warm to the touch. I'd guess 85 to 95 degrees (f). It seems pretty clear that the primary goal of having a significant temperature differential between the CAI and the SC has been achieved, where it was not being acheived before adding the thermal pad.

2) Whether or not my judgement has been affected by driving fatigue, involuntary auditory readjustment or just plain numb butt, the car still seems to be stronger, all across the power band (not just on startup). And it's strong enough more that I still notice it and get a little thrill as the seat presses into my lower back with relatively mild thottle application. My wife and sons still notice it. A friend who also owns a MCS noticed it. Without any tools, I cannot measure it, but so far I do think the power increase is real.

3) It's definately quieter. Noticably, by everyone who heard it after I got the CAI, the pulley and the 1-ball installed... The SC whyne is at least back to stock, maybe even quieter. While I was always amused by the SC whyne with the stock Alta CAI, I'm very pleased to have a quiet running car again. This to me personally is reason enough by itself to use the thermal pad.

4) With around 500 miles on it in this configuration, the filter does not appear to be collecting any dirt in spots from having contact with the thermal pad. If there is direct contact anywhere, it is minimal. The thermal pad is showing no signs of fatigue or heat, it is pretty much doing what thermal pads do well, insulate.

I'm still interested in testing another kind of thermal padding if I can find it, it is a type that I have some samples of, not corrugated like the current padding, but is still pretty firm and well behaved. If I can ever find it again I'll give it a try and report about it here. But for the time being the corrugated padding works very nicely and I've got more of it (albeit in green/offwhite) so I can repeat the process. Just need the thermal padding, a coat hanger and a paper clip.

It's worth mentioning that my Alta CAI installation still has the back partition in place, there's just a ~5"x~5" window cut out of it just below the molded cowl. Because of that there is some extra bracing that I can achieve with the coat hanger and paper clip, although I'm sure there are other ways of doing the same thing.

Like others here I'd be excited to see numbers associated with the result of cooler air going into the SC. I'm just guessing, but from what I've experienced in the driver's seat, there might be some interesting curves based on filter-air/SC-air temperature differential vs measurable hp change.

More later,

-- VBG

 

Just a suggestion. You can buy a cheap digital indoor/outdoor thermometer for $10-12. You can put one probe one one side of the pad and one on the other and measure the drop through the material.
Something to also bear in mind is the rate of loss of the material you're using.
Get a small piece and use a hair dryer to heat one side to whatever test temp you want. Check the opposite side.

Do the same thing with the other material.
That'll give you a decent idea of the insulating properties.

The other thing you might want to test is dissipation rate. Heat the entire piece(s) to a specified temp( 150º in an oven ?, when the wife isn't home! ) and then hang it in a still place like a closet. Measure temps 10 and 20 minutes later. Whichever dissipates best may be a better choice.

Have fun

 

Well, 2 things to update this thread with...

1: I've just replaced the original prototype corrugated thermal padding in my car with some newer corrugated padding that is cut a bit bigger for tightness and that has a slightly better R-rating. The new material is not black like I like, but it is very functional and I can live with dark green instead.

Whether or not the tightness and R-value helps reduce temperatures more, the SC whyne is even quieter now. Man I do like hearing my engine sounds...

2: I've just ordered a very simple and inexpensive performance computer from Escort, the GT1.

At this moment I can only imagine getting this out and hooked up when I'm on a special run or I have something specifically to test. That being the case, the price ($100), features, more temporary mount and the size of the Escort G-Timer GT1 seems much more reasonable. All I really need are a few result numbers for the testing that I'll be doing.

If this unit arrives ontime by Friday, I should have some HP, lateral G, 0-60 and 1/4 mile results of testing with and without thermal insulation this coming weekend. We'll see if it really makes any performance difference.

-- VBG

 

The GT1 wasn't available when I was looking for a performance meter. But welcome to the objective world of data logging and analysis!

Looking forward to the numbers....

Matt

 

Thanks, Matt, I'm really anxious to start playing with this.

Without a PC interface or multi-run storage, the GT1 isn't fancy, but it is considered accurate. I'll just keep a pad of paper and a pen handy and jot down numbers at appropriate intervals.

I'll try with and without thermal padding first thing, that way we can see if there is really any performance difference.

It's been stiffling here for the last couple of weeks as far as heat is concerned, hovering near or slightly above 100 degrees with high humidity. I drove a lot yesterday with 4 adults in the car and AC on. Heavy load is livable, but then adding AC is a big drain in city driving. My MINI has thermostically controlled AC, I've actually found it is less of a power drain if turn off auto-AC and control it manually, leaving it running, but at it's lowest setting. Have you encountered that?

With the heat during the day, when I'm alone in the car I try to leave the AC off and windows open. When it gets much above 95 degrees outside I start noticing that throttle response is less crisp, power lagging a bit, like it was before I started using the thermal insulation in the CAI...

I suspect there might be a threshhold for ambient air temperature beyond which insulation is ineffective and/or the intercooler is heat soaked and/or where the SC compression begins to fail to compress air successfully. I guess at that point one really needs an improvement with the intercooler, perhaps water cooling or a bigger one...

Have there been any studies of this here?.

-- VBG

 

"I suspect there might be a threshhold for ambient air temperature beyond which insulation is ineffective and/or the intercooler is heat soaked and/or where the SC compression begins to fail to compress air successfully. I guess at that point one really needs an improvement with the intercooler, perhaps water cooling or a bigger one...

Have there been any studies of this here?."

Many studies. So far the M7 solution ( air to air ) looks air to be the best Mini solution for $s spent IMHO. Just look for a STI with soot on the back of it, a large exhaust and the unmistakable sound of a big turbo, then, look at the front of the car & most likely you will see a very large IC fitted behind the lower front bumper cover.

 

our SC isn't a compressor. It's what's known as a posative displacement air pump. What that means in English is that it doesn't compress, it just stuffs the air out it's exit that it swallows in. The compression comes from whatever is downstream of the SC not swallowing air as fast as the SC provides it. If you think about it for a while, that means there is very violent airflow as the air exists the SC. At first, higher compression air flows INTO the exist of the IC before it gets pushed back out. This is one of the reasons that Roots blowers aren't that effiecient.

All pumps have a stall pressure. That is the pressure at which they will not push any air against. We're far from that point with our cars. But what does happen with our blowers is as you push them to higher RPM or pressure deltas, the efficiency of the blower gets worse and worse. You put the energy more into heating the gas than you do in actually increasing molecular density. This is why the twincharge kit is a good idea, or just using one turbo and throwing the SC away.

Baby's awake now, gotta go!

Matt

 

Thanks Steve and Matt... Like most good info, this raises more questions that I'll try to put into words...

Steve, has the STi IC under-the-front-bumper concept ever been eyed for MINIs by any aftermarket company? I take it that M7 has engineered this for the STi, or was you reference to M7 for their intake for the MINI?

Matt, interesting discussion brewing there about SC vs TC technologies, which or course is a whole nuther big topic...

Without getting wrapped up in that particular never-ending debate, how would you see our intake/thermal instulation issues being affected by having a TC instead of an SC?

Since the TC will be the case with the higher performance MINIs next year, it would be interesting to know what range of temperatures, as well as what aftermarket intakes and other mods that we'll be dealing with then.

I'm guessing a TC does not use a reduction pulley, is that accurate? What would be the equivalent of a reduction pulley for a TC?

Best,

-- Don

 

Yes. Webb Motorsports sold one
Cooling the intake charge is a good thing no matter what technology is used for forced induction. Cooler is always better it's just the implementation that may change.
CAIs will probably still be the rage and all your typical turbo tuner products will come into play. The manner of FI may change but the basics of performance don't. Better flow in and out is good.

Finally an end to all the "can I put a BOV on my supercharger?" threads.

No it doesn't

A larger turbo

 

 

Got the GT1, still have to learn how to use it better, so far in just testing it out, the highest HP reading I can get is 110; if I could get that consistently that'd be ok, but it looks like I also need to learn how to drive .

[edit 10pm, 7/7/06 I think I've got it dialed in now, I'm getting pretty consistent values for overall hp now. I'll probably try some tests tomorrow.]

Also devised another brace method to keep the thermal padding away from the filter. This is a drop in device made of acoustical ceiling hanger wire that keeps the thermal padding from touching the filter anywhere. It will work with or without the rear partition, which is handy because most Alta CAI users don't have it there anymore. Some local friends are interested in trying this out, so I'm starting to put together materials for a few orders.

[edit 10pm 7/7/06 Tried this too, it works! ]

Anyway, more later. Gotta go learn to drive.



-- Don

 

Ok, back again...

As mentioned, I got the GT1 performance computer, have it calibrated and setup pretty well now...

And, it looks like I'm getting some consistent overall horsepower values now.

As mentioned, over the weekend I was getting about 110 OHP, sort of dissapointing. Then I followed the directions and did my HP tests in 2nd gear between 30mph and 60mph (~3k rpm to ~6k rpm) and began getting more reasonable 132 OHP values, and more importantly, I'm now getting them consistantly...

Sooo...

I'm going to do some more tests in less hot temperatures (it's 98 degrees here now), either at night or in the morning, and will see where those values go.

Once I get a consistant range of ohp for lower temps, I'll test in high and low temperatures with and without the thermal insulation. We'll see where it goes from there.

In the mean time, a friend is testing the prototype thermal insulation in his MCS. Aside from road testing, he may also test it at a local Dyno Day this Sunday.

He does agree it is quieter. I'm not sure he likes that, but it is quieter .

Best,

-- Don

 

or more properly, drag, will lower the readings. There's a areodynamic loss calculator on the G-Tech web site.
http://www.gtechprosupport.com/support/
Click on the Aero Drag Calculator. I think 18 hp or so goes into moving air at 70 mph.... But that will get you closer to dyno numbers.

Matt

 

Cool, Matt, thanks for that reference...

-- Don