Cold air intake for 850's

csbrianp · Post by **csbrianp** » 14 Oct 2007, 23:43

I did this cold air feed on by turbo, and thought for many years it was the best thing going until I changed back to the original snorkel setup and had to turn my manual boost controller down because it kept reaching fuel cut levels. The only thing I can think of is it's getting more air to the air box causing it to over boost.

This air box modification is a good idea it just didn't work well for me.

Brian

rchotrod · Post by **rchotrod** » 04 Mar 2008, 22:18

I dont have anywhere to host images so ill just explain my Cold Air Intake. I have tested it through downpours and snowstorms and haven't had a problem. It has added enough HP that I can easily notice it. It also raised my city gas economy by 2mpgs. It will also rev more freely.

HA! figured out the image shack hosting thing. sorry i dont have better pics

I drive a non-turbo so my set up may be a little different than turbos. I removed the airbox, cold air intake plastic tube, and warm air intake pipe entirely. I left the MAF attached to the corrugated intake tube as before, of course I did unattach it from the airbox. I attached a cone intake filter with a heat shield around it onto the other side of the MAF. The heat shield has a 4 inch opening at the intake end. I placed the intake end in the exact same spot that the old intake drew air from. I noticed that it didnt sit all the way down for maximum intake efficiency, so I just hacked away some plastic at the bottom of the intake gap on the car. I set the intake back in and secured it with bolts and zip ties. It looks somewhat professional.

I had an SAS line so I put a breather filter on it and secured it behind the battery. There was also a small white plastic tube. I pulled off the big black end and then i drilled a small hole in the bottom of my breather filter. I drilled through rubber, so when I put in the white tube it sealed nicely.

On the warm air intake hose, I capped it with a threaded high temp pvc cap. I have had no problems with it

Post by **tjts1** » 12 May 2008, 10:26

I put together my own quick and dirty intake over the weekend using about 2 feet of 3.25" (the outside diameter of the intake at the airbox) flexible tubing (thank you McMaster). The intake is routed through the same hole over the top of the radiator as the original factory intake. The main difference is that i trimmed some of the plastic from the top of the radiator fan shroud in order to make more room for the intake. This gave me an extra 1/2" of height at the radiator. On to the pics.

Comparing the stock intake tube (left to the 3.25" flexible tubing.

Take a 3.5" hose clamp to attach the tubing to the airbox.

And install it back in the car.

The tube had to be squished down a bit in order to make it fit between the top of the radiator and the fiberglass cross member. I also trimmed the front of the cross member a bit in order to allow a more direct air path.

This version isn't as large or efficient as the original post but its easier to package and doesn't interfere with as many hoses and wires. The factory intake was designed to first and foremost control intake noise, hence the extremely squished design.

ibailey · Post by **ibailey** » 25 May 2008, 18:04

I seem to recall, Lingenfelter (i think it was them) adding extra non-boosted hp by freeing the intake pressures on the stock air box of mid 90s model Impalas. This was done very simply without the hassles of tubing and snorkels and valvature.
Amazingly, they took a hole saw to the unfiltered side of the air box. The underside to be exact, as I recall, they put two 2 1/2"-3" holes in the bottom of the filter housing, all under an aftermarket air filter (k&n factory type filter).
I don't remember any numbers as far as hp gains or losses, but I believe that it could free up some power and I don't if it worked or not but a buddy did it to his Chevy Impala and the sound was impressive if it didn't make a difference in performance.
Any Ideas? Would this work on an Interference Engine?

Post by **MadeInJapan** » 25 May 2008, 19:28

That should work...biggest problem is with heat soak on these turbo'd engines...especially in the summer time. There are many designs out there similar to what you have described.

ibailey · Post by **ibailey** » 25 May 2008, 22:14

Yeah, i know those turbos throw some heat out there, I have the NA base model, so any flow improvements couldn't hurt

_HighVoltage_ · Post by **_HighVoltage_** » 07 Apr 2009, 22:48

The previous owner has put a new air intake on my new 850 NA, but I'm not too happy about it...Look where it is.

How is it getting enough air is beyond me? There is no tubing, to route fresh air to the filter. Any suggestions on how to improve the current setup?

Post by **matthew1** » 07 Apr 2009, 23:19

With those cone filters it's also a matter of the temperature of the air.

Sucking air in from the engine bay is a sure way to get the hottest air possible. Cold air is denser -- has more oxygen -- and that means more power... until the point at which the fuel delivery system can't keep up. That bridge is far down the road, so don't worry about it.

This very thread has some simple, cheap ways to pull in fresh air:
https://www.matthewsvolvosite.com/custo ... ification/
viewtopic.php?p=59606#p59606

_HighVoltage_ · Post by **_HighVoltage_** » 08 Apr 2009, 07:49

I've looked at those, but I'm still out of ideas...It would've been a lot easier if I had the original airbox.
Maybe If i run a tube from the front and just point it at the filter I'll improve things a little bit?

Post by **matthew1** » 08 Apr 2009, 09:56

Yea, that be about the best you could do without constructing your own intake shroud. Or driving with your hood up.