I just installed an Alta CAI, and am less than thrilled with the overall quality. The hose doesn't seem like it fits perfectly, and Im getting a high pitched whistle around 2-3k rpms. I've been told that its just the throttle body opening up, but with the way the hose fit, I wouldn't be surprised if it had a small air leak. It seems everyone who complains about the whistle has the alta hose... Im trying to narrow it down. Either way, Im not fully confident I have a tight seal, and I dont want to risk ruining my engine by sucking in dirty air.

Question is this: Can I swap out the hose and upper airbox from an alta and use the Dinan upper box with an alta filter? Im guessing the high pitched whistle is related to the alta hose, and want to go back to the stock. The stock hose wont fit on an alta upper airbox, so now I need a different one. I guess I could get rid of the upper airbox all together and use the stock hose with the alta filter... Anyone have that combo? If so, does it get rid of the whistle? Has anyone experienced the whistle that has an OEM hose?

Oh, and to those who say they "like" the whistle... Im not talking about supercharger whine. This is high pitched like a brake squeal, nails on chalkboard, dog whistle... etc.

 

The whistle is the throttle body butterfly. All cars make the noise, the Alta simply allows more of the noise thru the filter. This is the only problem with the foam filters.

I am sure you could go back to the stock intake tube, lots of folks running the intake w/o the silicone tube.

 

MANY MANY MANY members have complained about the whistle with the Alta intake. I have been running the Alta intake with silicon hose for about a week now. I only notice a slight whistle, at a specific rpm in partial throttle. Overall, I love it.

You're right though, the way the Alta hose fits on the throttle body is not very good. Mine took a little bit of trial and error to get it right.

 

I have the stock tube and I get that whistle. Nothing that bothers me though. Everything is nice and tight as well.

 

I think I'll ditch the silicone tube and go stock just to keep it nice and sealed. Its kind of funny, the hose was about 4-5 inches to the left of the airbox connection after it was connected to the throttle body. I had to bend and tweak it so much it makes me think that if I go over a speed bump too fast it might just come off. Its got sooo much tension pulling on it...

Anyone know if the Dinan airbox will fit an alta filter?

 

We've had alot of people complain about the whistle, that's one reason why we prefer the DDM intake. But you can try to fix yours. First thing to do that would be FREE, would reinstall the plastic firewall divider. If that doesn't work add the box top lid, but that will cost you $30. Or you can replace the air filter with a different UNI filter, or a K&N filter.

 

@WMW - Is this why the JCW only open up at 4500k RPM? That makes sense.. If I replace the firewall, wouldn't that block off all crowl air, and negate most of the benefit of a CAI? Lastly, are foam filters louder than the rest?

 

Here's a pic of how much room was left after I hooked up the hose to the throttle body and smaller hose on the side. Theres lots of room, and i had to bend the hose to get it to fit.



and the fit..

 

I have the Alta CAI, using the stock hose, and I have that whistle, but I've long since gotten used to it. It doesn't even bother me. The glorious jet-engine whine of the supercharger trumps anything negative!!!

 

That's definately not right. Can you rotate it on the TB at all to bring it closer?

 

If I were to bend it closer, it would pull out the smaller hose on the side, which was already coming pretty close to detaching.

 

Wow that's worse than what I thought .

 

Dang... something is wrong with that hose. Where did you order from? Maybe try contacting Alta and see what they say. Sorry for your luck.

 

Ordered it from Alta.... I think I'll shoot them an email.

 

Are you sure you have it right side up?

 

Yes I tried the opposite way, and its not even close. Good thinking though! Everyone has the Alta logo facing upwards too, right?! right?!

 

burley, off topic but is that a aftermarket intercooler? or did you just take off the OEM diverter?

 

Just took off the diverter so I could better access the hose.

 

I'm pretty sure you're ok. I can tell you the smaller hose fitting really tight on the side is fine. Mine fits exactly the same. If I remember right, I had to bend the entire tube a bit to fit it on my intake box as well.

 

Should you have to bend it almost 6 inches to get it to fit? Are they ALL like this?!

 

I'm about 250 miles from my car so I can't really go out and check for you. But I can say for a fact that the tube on the side it supposed to fit that tight. At least mine does.



I mean from looking at this pic, everything looks ok to me.

 

just installed mine and it fit exactly the same. my mechanic, whos done many installs of these, said they are all that way. he looked at mine and said it looked like i had it all right too. when i asked alta they said it was designed to be pulled so it didnt rest on the supersharger and melt.

 

Must of gotten lucky as mine was great quality and fit just fine. Still have not heard this sound everyone is so upset about.

 

Why don't I listen to people before I order....

I really hope mine isn't like this.

 

I will probably sell my Alta intake in the summer and get the Dinan intake. Nothing against Alta but that whistle is kind of annoying.