Is the swirl bar actually needed?

**justin32** · 9th October 2011, 23:19

Over the weekend me and a mate worked on his 2004 sri 150 and 1 of the jobs was to reattach his swirl bar that had come off.He had no idea that it had come off and the car was running fine.All the swirl ports were easy to rotate(we didnt touch the 3rd one that runs of the motor) so assume they are not stuck,we attaced the swirl bar and took the car for a spin,the car ran exactly the same but is using more fuel.

If the swirl pots arnt stuck and move freely can the bar just be left off?

Another forum member posted on the £1 swirl bar fix that he left his off and is getting better MPG and the car is running fine

What do youthink guys?

**GazVXLINE170** · 9th October 2011, 23:43

Technically you do need it as it increases the torque at low rpms. It was off on mine and did I notice lack of power low down? no but it apparently keeps torque up at low rpms.

**justin32** · 10th October 2011, 01:01

What does the bar actually do then? does it just open the flaps to let more gasses out?

**GazVXLINE170** · 10th October 2011, 01:07

It closes the flaps over at low rpms to produce a 'swirl' or 'tumble' effect in the cylinders. It also increases - in theory - low down torque. At about 2,500rpm the rod is used to open all the flaps and allow high volume airflow into the engine.

**justin32** · 10th October 2011, 01:16

I seeeeeeeeeee

Ill pass on the info to my mate as he was really worried that the car would be useless if the bar wouldn't go on and stay on.Its a bit of a rubbsh time for him as its MOT time in a few weeks and 1 of his wheel bearings is on its way out and also by the sounds of it his DMF is starting to go....not good with the run up to xmas

Thanks again mate

**dh.dti** · 10th October 2011, 16:02

As long as the the flaps are not stuck in the closed position it will run fine, there's probably a bit of boost leaking from the top of the pots but that's about it really... you can remove the flaps & seal up the manifold & it will run fine, slightly lean low down but that's it really.

**robdd1** · 10th October 2011, 18:45

My swirl bar could of been off for months and I never noticed a thing. Only after reading this forum did I find it off! With new manifold on again I really didn't notice much difference.....

Saying that the car used to do about 150 miles a week on 50/60 mph roads mostly.

**ted** · 10th October 2011, 19:15

I remember disabling my swirl bar and leaving it in in the fully open position a couple of years ago, just to see what effect it would have (I'm nosey that way)
Must admit it was noticable, low down torque, the main reason I run a Diesel, was much poorer.

Reminded me of the feeling I had in my younger days when I hankered after the then new 16 valve mk 2 Golf GTI, tried a pals one and had to lie through my teeth when he asked me what I thought of it!

Total torque free zone till it got above 4000 rpm, my 8 valve mk1 was a little rocket way down in the rev range by comparison

Restricting the inlet tract does seem to boost torque on an engine, opening it up later in the rev range lets it develop its top end BHP.