My revised Simota thread and air way mod
- Thread starter windym
- Start date
STONE HIM
Don't forget to tell your insurance brokerHit the dissertation silly over tired wall today, brain has turned to mush, cant wait to fit it though.
Andy
- Joined
- Oct 10, 2015
- Points
- 123
Well here,s a thing finally got round to working on my Simota, basically I bought the carbon surround off eBay for £20 and used a voucher. Then found a new 6" filter, housing, banding and trumpet for £25, the problem was the trumpet was too small and reduced the air flow through the system.
This would have been acceptable on the 1.9 but not a tuned 2.8 so had a think and off to the plumbing shop for a reducer.
Found a 5"-3" ducting reducer and started to cut it about this morning to get it to fit.
So cut a section of the top of the reducer and used it as a locating piece to fit in the filter.
Then cut the bottom of the reducer to size so it would fit to the rubber gasket and make a seal
This now fits snuggly so just have to clean it all up and wait for the trumpet that should be here this week, then fit and enjoy the easy breathing.
So no air flow restriction and a fully working Simota for all in £58.00
Andy
This would have been acceptable on the 1.9 but not a tuned 2.8 so had a think and off to the plumbing shop for a reducer.
Found a 5"-3" ducting reducer and started to cut it about this morning to get it to fit.
So cut a section of the top of the reducer and used it as a locating piece to fit in the filter.
Then cut the bottom of the reducer to size so it would fit to the rubber gasket and make a seal
This now fits snuggly so just have to clean it all up and wait for the trumpet that should be here this week, then fit and enjoy the easy breathing.
So no air flow restriction and a fully working Simota for all in £58.00
Andy
- Joined
- Oct 10, 2015
- Points
- 123
Thanks mate - I heard they were the distributor but didn't want to believe it going by their website!
- Joined
- Oct 10, 2015
- Points
- 123
So just made a modification to the cars air flow and intake. After fitting the Simota the difference in smoothness through the rev range was very noticeable. Also the gear changes seemed to be smoother, I could hold the car in one gear for longer loosing the jerky feeling that had been there.
One thing that had bothered me was on start up the car still felt like it was searching for air, it felt lumpy. I know this is a 1.9 and not as smooth as the 6 cyl cars but just did not feel right.
So looking at the air passage to the Simota it was obvious that it was restricted by some bodywork, see pic below.
When the bonnet was closed this just closed of any access to the filter, so at standstill with no ram/pressure effect no wonder the engine still seemed starved.
Had a look at @Rha kitchen bin filter system and I guess he must have had the same opinion as me. Now he made a scoop for his after cutting away some of the metal, I was a bit dubious about cutting but after having a good look around the area, decided there was nothing structural.
So got the hacksaw out, see pic below.
So now I have a clear passage for air to get to the filter, this is a pic through the grill.
So outcomes, started the car and IMHO a lot smoother on tick-over also there is a new induction noise I had not heard before. Pulling away I can hold the car longer in the gears and it has eliminated the jerky 1st -2nd gear change. Now I was happy after I fitted the filter but now it seems even more responsive and again smoother through the gear change.
At higher speeds the car always seemed to be holding back, on the run I have just done this also has been greatly reduced, in fact almost not there at all. And to cap it off I have a great induction sound that was not there when I first fitted, I will look into modifying the air passage with a scoop in the near future but for now I need to slightly adjust the fit to the Simota.
Andy
One thing that had bothered me was on start up the car still felt like it was searching for air, it felt lumpy. I know this is a 1.9 and not as smooth as the 6 cyl cars but just did not feel right.
So looking at the air passage to the Simota it was obvious that it was restricted by some bodywork, see pic below.
When the bonnet was closed this just closed of any access to the filter, so at standstill with no ram/pressure effect no wonder the engine still seemed starved.
Had a look at @Rha kitchen bin filter system and I guess he must have had the same opinion as me. Now he made a scoop for his after cutting away some of the metal, I was a bit dubious about cutting but after having a good look around the area, decided there was nothing structural.
So got the hacksaw out, see pic below.
So now I have a clear passage for air to get to the filter, this is a pic through the grill.
So outcomes, started the car and IMHO a lot smoother on tick-over also there is a new induction noise I had not heard before. Pulling away I can hold the car longer in the gears and it has eliminated the jerky 1st -2nd gear change. Now I was happy after I fitted the filter but now it seems even more responsive and again smoother through the gear change.
At higher speeds the car always seemed to be holding back, on the run I have just done this also has been greatly reduced, in fact almost not there at all. And to cap it off I have a great induction sound that was not there when I first fitted, I will look into modifying the air passage with a scoop in the near future but for now I need to slightly adjust the fit to the Simota.
Andy
Not sure if you've seen this before, but it's a scoop which grabs air as it goes through the grills on the Z4 and then directs it towards the airbox. It has a slight ram effect, but seems to increase air flow. I was tempted to try something like this when I started the power project on my 2.2i.
No one as yet (as far as I know) made one for the Z3 so far.
In the first picture the RPI scoop is on the left and the OEM one on the right.
No one as yet (as far as I know) made one for the Z3 so far.
In the first picture the RPI scoop is on the left and the OEM one on the right.
I need to make something similar for directing air around the back of my wheels and into my air box to replicate the OEM M bumper airflow parts. I would start with the original bits if I could find the part numbers on realoem
- Joined
- Oct 10, 2015
- Points
- 123
Thats quite a difference in size for air gathering, I find it strange that BMW did not work out a better induction system. The difference is very noticeable after my mod, even if the HP gains are small the driving experience is well worth it. I was looking at the rest of the metal work I cut away, it appears not to be structural but does add support. My thought are to fabricate in plastic and see if it is possible to recreate in fibreglass or ABS.
Has anyone else had any experience with this?
Andy
i'd imagine that BMW actually spent a lot of time and money designing it to work.
But they have to take a lot more into consideration that us just wanting more noise.
that front piece may not appear structural but might have a purpose but i dont see any harm in chopping it out and adding in somehting that actually directs air into the right area.
But they have to take a lot more into consideration that us just wanting more noise.
that front piece may not appear structural but might have a purpose but i dont see any harm in chopping it out and adding in somehting that actually directs air into the right area.
- Joined
- Oct 26, 2014
- Points
- 181
- Model of Z
- Z4 coupe sport.
Nice work @windym, all you need now is something to direct the air off to the right towards the filter even though you'll get some going that way. Been looking at mine and because it closes so tight to the bonnet it's actually gone a little quieter, all I need to do now is get a larger full mesh filter back in to get that lovely hiss noise back ( K&N is OK but too quite closed in) which I had with the stealth filter that is a fraction too big for the waste bin. @Antm72 has made a great induction closed filter shroud which looks so much better than mine. The Z4 one just goes to show that BMW has leaned something from the Z3 6pot lack of decent air path to filter, now I'm impressed with that scoop on the 4 to the point that I'll see if I can get one to fit the 3, nice one @GazHyde. Shows I didn't do my homework on the Z family.