Hi All
I might be being thick here...... Or Naive.... Or both
If you put a Vent to Atmo Dump valve on, the car runs rich because the Air is not being recirculated (ie less air).
Yes/No

If you fit an Induction kit say a 57i the car runs lean because of better air flow (ie more air).
Yes/No

Now if the answer is YES to both would one not cancel the other out and balance thing back up there abouts....


I already know the answers not that simple. But why not??????


All the best
Pete

 

If you use a VTA valve, the car can run rich for short periods of time whilst the valve is releasing pressure. If you use a K&N 57i then the car could run a little lean (depends on your state of mapping). However - that would probably be uniformly across the scope of usage, and not occasional per the rich periods due to the VTA valve. i.e. no - they would not counter each other out.

 

Just to add that the VTA causes richness because you dump charge that the ECU assumes is still in the system. So the ECU sees more air going through the MAF, and adds petrol to compensate. Only the air isn't really there. So: richness on dump.

 

So is having a rich dump a good thing or bad then?

 

Bad!

 

Ok, so I best not fit a HKS SSQV to my STi5 then

Nevermind...

 

Just to say that upon fitting a K&N 57i filter to my MY97 I noticed no change in AFR (Dawes AFR meter - blue light on WOT)...

Doesn't pop as much with the standard dump valve back on but sounds better IMO.

 

Right then
Question 1. Would you fit a K&N 57i and vent to Atmo Dump Valve
To an MY01.

Question 2. Is the MAF in an MY01 fragile (likely to fail) as it appears all the MAF problems occur on older models?

Question 3. Are there any gains from fitting above????? apart from induction noise and whoosh...

All the best
Pete

 

Pete,

1) No
2) Better than the 99-00 which was worse than the pre 99
3) probably not

Matt

 

Thanks Matt