factory bov????

[knob city]

hey guys, just wondering, do T1's have a bov from factory? because i've put a pod filter on it and it sure sounds like it does. if not, what am i hearing?

[Damo80]

probably blow back air out of the pod filter, which will sound a bit like a "woosh" noise.

Although, I'm not a T1 expert, so cant confirm - I would assume it would have a factory BOV. but factory BOV would not vent to atmosphere so I doubt thats what you are hearing...

so, yeah, I will go with my top answer

Damo

[connorling]

then how do u cure the problem???? what cause the air to go back out of the filter?

[ClassicProT]

To my understanding, if the car isn't fitted with a BOV, the compressed air from the turbo has no where to go then the throttle body is closed (i.e. when you momentarily shift gears). The blocked compressed air in the piping then turns around and heads back up and out of the turbo compressor.

I think this becomes a significant problem when you run high boost levels...The last thing you want is the compressed air heading back to the turbo when it is spinning in excess of 200,000+ RPM causing the shaft to rapidly slow down. Hence why you have a BOV.

[3GCVC]

It should make a fluttering noise the above post pretty much sums it up if you want to get rid of it get a blow off valve mounted.

This is a little difficult with the T1 throttle body top so i used a T2 one as its a bit taller and easier to plumb, I just used a straight piece of exhaust tube off the turbo outlet and the stock T1 bend from there to the throttle body inlet then welded the flange for the BOV in the middle,

[connorling]

i have got the bov working, but it still can hear the air rushing out of the filter at lower revv. at high revv, both air filter and bov makes noise.

[Damo80]

i have got the bov working, but it still can hear the air rushing out of the filter at lower revv. at high revv, both air filter and bov makes noise.

well as ClassicProT its not really something to be too concerned about, all turbo cars do it. Just a problem if you start to run rediculous amounts of boost - which the little City motor's won't be able to handle anyway - so don't stress, just enjoy

Damo

[ClassicProT]

It also depends on what type of BOV you have. As in, the actuator in it might be calibrated for high boosts. Hence the BOV will only open under high boost pressure. While at low boost pressure the BOV won't open due to insufficient pressure to move the actuator.

If your BOV is adjustable, play around with the sensitivity.