On my 240 Sedan, the exhaust manifold has the little pipe coming off of it that vents hot air into the air intake box. I have read that the flap inside that cuts off or lets in hot air can easily get stuck open and let nothing but hot air in, which could lead to a cooked MAF sensor. In order to prevent this from happening, I wanted to install a cold air intake so that I can eliminate the air box all together.

Are there any cold air intake kits for sale for the Volvo 240? I have searched around and the only one I came across was discontinued. If there are no kits, I figure I could take out the air box and fit a conical, cold-air style filter to the intake piping to help it breathe better. Am I correct in thinking this?

Once a CAI is installed, it leaves the issue of that preheater pipe coming off the exhaust manifold. At one point, there was no piping connected to it and it made the car sound like a bus and ruined its backpressure. Is there something (purchased part or DIY fix) I can fit to the manifold to cover the preheater pipe?

Thank you for any assistance you can give me in this!

 

just wire that hot air flap closed.

there's already a cold air intake in front of the radiator, its very effective. the stock rectangular air filter works much better than any aftermarket cone nonsense.

the preheater pipe off the manifold is NOT connected to the exhaust ... its just a heat riser plate around the outside of the exhaust manifold. if removing the pipe made your car louder, your exhaust manifold is likely cracked.

 

How do you suggest going about wiring it shut? I tried to figure out some way to keep that flap closed and I was stumped.

 

steel fence bailing wire around the little arm that the thermostat/spring thing is on... I dunno, I did our 87 about 20 years ago

 

Drive a screw in it.

 

Snag an k&n air filter for it too!

 

K&N Filters are pure garbage. they don't filter well, they get the intake tract greasy, and their horsepower claims are a joke. there's numerous tests online where people compared a very clogged stock air filter in various engines, sometimes even covering 50% of a heavily used filter, and dyno testing that against NO air filter, they could find no differences. so how is a oiled-paper filter going to do anything?

its also been shown in numerous tests, you run a K&N filter, and you will end up with more silca particulates in your engine oil. the stock volvo paper filters are very effective, inexpensive, and don't have to be changed very often at all.

 

Welp..Op snag a volvo filter. Haha

 

Oh man! I was on my way to the parts store, to buy a $40 dollar magical cone, to improve 5 horsepower on my 65 horsepower car. You crushed my dreams.

 

a B230F should be good for about 115HP in stock US tune, and 136 ft-lbs of torque. the b230FT turbos are like 160HP and 225 ft-lbs, I think.

now, if you have a higher-than-stock compression engine, with flow-ported heads, bigger-than-typical turbo, high lift cams, bigger injectors (and fuel pump) and about every other tuner trick out there, you MIGHT find the stock intake tract to be a bit restrictive... but that would be somewhere well north of 250HP.

 

[QUOTE=pierce;351420]a B230F should be good for about 115HP in stock US tune, and 136 ft-lbs of torque. the b230FT turbos are like 160HP and 225 ft-lbs, I think."

My owners manual says 160 hp and 187 foot pounds of tq @ 8psi of boost.

 

and this owners manual says 195 lb-ft. 1992 Volvo 740

hmmm. anyways, its a pretty decent amount of torque, which is why these wagons can haul off the line pretty quick once they get into the boost. hah!

 

Me have no turbo. and you guys are pretty serious with sarcasm over here. I fregging love my wagon by the way. My car is completely stock, and it will stay that way drivetran wise.

 

hmm.. true. haha.

 

I have had a 93 240 for about a year now and always thought the engine seemed to be running hot (hood always felt real warm - almost hot) and stumbled on the CAI flapper and sure enough - mine was stuck open. I'm in Denver and there are some cold times, but winters are usually mild. I took the air box out so I could remove the flapper mechanism altogether and then I taped up the hole on the box where the crinkle hose from the exhaust manifold connected with an aluminum tape and put it all back together. The engine is a lot quieter now. It will be interesting to see if there is an improved MPG - right now I get about 18 or so.

What temps really require the hot air to be in the CAI? Just wondering if I'll be ok without the crinkle hose in there or if I should look to rebuild the flapper (or replace with a junkyard one if I can find one).

 

I recently drilled and zip tied the flapper door shut in my 240's air box. The engine seems to run noticeably better, with crisper acceleration now that it only receives cool air.

 

I've donemuch the same, wired it shut with a bit of bailing wire.

they don't help starting anyways, since the exhaust manifold isn't hot when the car starts. my assumption is, sub-0 (F) weather, getting prewarmed air helps with atomization of the fuel. since its rarely even 0C here, I don't bother.

 

My first tank of gas after taking out the hot air intake and closing that side (as to only allow the cold air now), I registered just over 21 mpg (where as before I was only getting around 18 - which I wasn't too happy about). I'm not sure what kind of mileage I should be getting. It certainly seems to have more pep. I had added some gumout additive and used a higher premium gas (out of curiosity) in this last tank. Now I put a mid grade gas and no additive for this round and I'll see if the mileage stays decent.

 

a non turbo automatic should be getting around 25mpg in town, and as high as 28-29MPH on a long highway trip if you don't leadfoot it.

a turbo will get maybe 16-18 in town with my typically brisk driving, and 22-23 on the highway no matter how I baby it.


I just wish my 1992 740 turbowagon had a larger gas tank. its 14 gallons, so at 250 miles, its starting to look empty.

 

Anyone have pictures of what you're talking about? Sounds like there are a couple different things going on in this thread. There's that little stove pipe piece that sticks out the top of the Airbox, what's that for? Some of you are talking about something connected to the intake, and others are taking about closing the flap in the Airbox. Do I need to remove the Airbox to access this? Any further instructions and pictures would be of great help. Thanks!