Airbox thermostat failure...

Post by **tjts1** » 13 Jan 2008, 11:29

I completely gutted mine to free up some air flow.
Before

after

leftovers

If you are interested in picking up much sharper of throttle response do this.
http://volvospeed.com/vs_forum/index.ph ... try1168946
It makes a world of difference on a 5 speed where throttle response determines your clutch engagement point.

We did a 1900 mile road trip over new year break from San Francisco to the San Juan islands in Washington state. The 855 averaged 26.5mpg for the whole trip including 2 stretches with chains on and about 200 miles of local driving. Highway only fill ups came to 29mpg on 87 octane.

Post by **MadeInJapan** » 13 Jan 2008, 11:50

Very cool. Let's hear some more comments on this. If this is a viable thing to do long term on your N/A 850's I'll pin this in the repair database.

cn2000 · Post by **cn2000** » 24 Feb 2008, 13:55

I just wanted to add that when I was in the shop we used to replace these t-stats on cars which failed the NOX portion of the smog tests. The cars with a "hot-air postion" stuck t-stat or hot-air leak will produce dramatically elevated NOX emissions due to excessive combustion temperatures. That little sucker is not to be understimated. So you're even helping the environment by replacing it!

vroller · Post by **vroller** » 01 Apr 2008, 22:15

Hello there,

I'm new here and like many others before me I must say this is a really great site (thanks Matthew!).

Last night, I found the flap that blocked 'straight-on' air intake from above the radiator and having removed it, the car does seem more eager off the mark

But like some others who drive a T5, I found no hot/cold air flap in my airbox nor in the air intake plumbing.

A K&N filter is next on the list. I've been holding off on aftermarket/improvement stuff for fear of 'adding problems' to what is already a rather complex and not inexpensive to maintain/rectify car, lol but thru this forum I've found the confidence to do so.

On another note, we have an indy over here who supplies reconditioned ABS control units in exchange for faulty ones for RM400 (approx. USD120) plus labour with a 3-month warranty. Great find especially in view of the cost of a new one (RM2,000 plus) and the fact that I don't have the tools to saw open the casing and re-solder (not to mention a fair amount of skill and patience) the bits in the motherboard.

162,000km on the clock

Post by **kelvin6** » 02 Apr 2008, 00:51

And my beautiful thread continues...

Many of you don't know, but my NA is dead, due to accident (was hit when it was parked). Now I replaced it with a 98 S70 T5.

So I was 'swapping' some parts over from my old car, and got to look at the airbox in my NA one last time (the insurance company will tow it away) and looking at that simple little fuel clamp thats holding the valve open... oh man, i still remember how much it improved the performance and fuel economy. I still insist that every NA owner check and if desired, jam that airbox open to the cold side!

dcunited122 · Post by **dcunited122** » 24 Apr 2008, 14:59

question, I know this sounds great and all, but what was the purpose of this in the first place? Is this safe to do?

Post by **Ozark Lee** » 24 Apr 2008, 16:00

Its purpose was to allow the car to warm up a bit quicker. It is totally safe to eliminate it. On the coldest of days it takes my car about 1/4 mile further to get up to full operating temperature with it jammed to the cold side.

...Lee

DoctorDeathsBay · Post by **DoctorDeathsBay** » 26 Dec 2008, 21:29

How about just cutting out the thermostat with a dremmel to make a smooth, flat air intake stream (as seen in the pictures before hand) then completely removing the flap as well.

Surly the cold air being sucked from the front of the car would even out the hot air being sucked from the exhaust pipe?

Might this mean better warm up time than just all cold air, maybe better mpg and possible more available air to suck as the airbox Y connector has now been opened up for more airflow?

What do you think.

Also how about the 'Snowguard' at the front of the car just covering the front of the air intake pipe. How about cutting this little portion of plastic off for increased air flow?
Could water get into the airbox? Umm.... I'm not sure there.

If any one has done any of these, please could you comment on how it went, weather you did get better mpg or maybe you got water inside the airbox from cutting the piece of plastic in front of the air intake tube .. 'Snowguard' ..

Post by **Ozark Lee** » 26 Dec 2008, 21:59

Others have completely removed the damper flap but, in the specific case that I recall, they wadded up some tin foil and blocked off the hot air side of the "Y". Without blocking off the hot air side it will still increase your intake air temp with the mix and any minor gain in flow is killed by the temperature increase.

I found it much easier to just force it open to the cold air side. That can be done without even removing the airbox, just take the top of it off and remove the filter and you have all of the access you need.

...Lee

Post by **tjts1** » 27 Dec 2008, 01:32

Quickest, dirtiest, cheapest setup by far.

I had the the pleasure of test driving a stock 1996 NA 5 speed sedan back to back with our 1996 NA5 speed wagon with the fixed cold air intake recently. WOW! I can't believe how pathetic the throttle response is on the stock factory intake setup. The first time I completely stalled it because I wasn't used to how much throttle input it takes just to get the car moving from a dead stop. Take the time and follow all 3 steps to a quick and dirty NA intake.
http://volvospeed.com/vs_forum/index.ph ... &p=1185167