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Air Box Thermostat? 200

Questions...my internal airbox thermostat/flapper was halfway broke. I broke it all the way...anyways, after breaking it, I thought I better remove it and the hot air intake hose from the manifold. In doing so, I now have somewhat of a forced air intake from the front of the car and an open hole on the bottom of the air box now. Should I plug the hole (where the hot air intake was)? Do you think it is robbing air from my front forced air intake? Or does air intake not really matter on an '81 245? It's gonna suck what it needs to suck, right? If more air is better, should I hole saw some holes in the airbox? Anyways, I want airflow...maybe a cone conversion? If anyone wants to comment, thanks.








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    Air Box Thermostat? 200

    If you are going to plug the hot air inlet in some way, make sure you have the flapper valve securely fixed in the cold air position, or removed entirely. Otherwise it blocks the cold air inlet off...so you have no air.

    There's no point in enlarging airbox holes or making more of them. You have a ~100HP engine there, and the stock inlet and filter is more than big enough to feed that. Look at your inlet snorkel in behind the grille - its opening actually faces away from the airflow. This is to prevent force feeding of bugs, rain, snow, dirt particles, etc, into the inlet system. Stick with the way Volvo made it.
    --
    Bob (son's 81-244GL B21F, dtr's 83-244DL B23F, 'my' 94-944 B230FD; plus grocery-getter Dodge minivan, hobbycar 77 MGB, and a few old motorcycles)








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    Air Box Thermostat? 200

    I took my T'stat out and deleted the Hose to the Exhaust manifold. I left the hole open. Other then the feeling knowing the AMM is safe, I notice zero difference in anything. The Airbox setup is not a forced air setup. The engine is not Blown or Turbocharged. It will Breath as it wants to.
    --
    '75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me








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    Air Box Thermostat? 200

    Yeah, plug the hot air side with a bit of aluminum tape (I used high heat tape, though I am not sure I really needed anything other than duct tape), then slide the hose back on. Internally, just prop the little door open to the cold air side. I think this is what most folks do -- the thermostat is prone to failure and that can kill your AMM, so just get rid of the problem as preventive maintenance . . .








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    Air Box Thermostat? 200

    Hi Robbert

    I had the thermostats on both of my 240's go bad and rather than buy new ones I just plugged the hot air inlet as you have suggested and all has been just fine. The only time the heated air intake is of any benefit is as the car is warmming up and for emmisions sake. It did Not make a bit of difference in performance. And rather than have them fail again, and take a chance on them over heating my mass air meter and killing it I have simply chosen to eliminate that possibility all together. And it work just fine.

    Bill Nelson Hartford, WI








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    Air Box Thermostat? 200

    I'd say seal off the hot air box hole as you want colder air = increased Ox content. Although arguably it's hard to predict how much air would be drawn in..
    --
    Norm Cook Vancouver BC; 1989 745T 204,000KM








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    Air Box Thermostat? 200

    The shape and volume of the airbox are very important for proper air flow and peformance. You can plug the hole or reconnect the hose. Don't need the flap unless it gets cccold (well below freezing) in the winter/early spring where you and the 245 live.







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