Surbo (Suction Turbo)

This was mentioned on one of the Fordmondeo.org Forums and made some big claims for little cost. I was very sceptical at first. But to give the Surbo guys credit, they did respond to the postings and try to give helpful insights to its workings

Take a look at Surbo.co.uk for details. Their explanation involves complex interactions between the device and inlet pressure build-up triggered by engine overrun when the user eases off for a second during acceleration

As they were so bold in their claims, but had no data to back them up, other than some user postings on their site. I offered to use the Molemobile and its AP-22 accelerometer to quantitively test the device. So on Saturday 15/12/01 I visited the London agents house to fit and test  the device.

I'd done some runs that morning before I went to set baseline times for my car (it was quite cold that morning, around freezing). I decided that a 20 - 50 MPH run in second gear would be the best to show off the device, as it removes the user variables of pull away and gear changing and sweeps the whole rev range, so torque and power come into the equation. It also uses part of the rev range that my car is very poor in

Here is the average results of my mornings runs

We then fitted the Surbo. I was amazed when I saw the device. It is nothing more than a painted and riveted, cut up coke can. No wonder they wont put pictures on their web site

View from the inlet side showing the riveted construction method. Note also the huge rubber grommet we had to fit to sit it in my inlet tube (which is narrower than standard)

View from the downstream side showing the vanes

Looking at the device you can see that their is no way this works by causing back pressure as it has no way of containing it. The only way this could perceivably influence the air flow is by spinning it, to create a venturi type effect. The vanes are not flexible and cant collapse.

So we fitted the device to my car in the top end of the alloy pipe

where the rubber MAF adapter sits. Now my tubing is 70mm wide and the Surbo is approx 50mm at most. It comes with a large rubber mounting cone which can be cut down to fit it in any system (bear in mind the normal Mondeo inlet is bigger than mine but corrugated). So approx 50% by area of my inlet was now blocked

We then repeated the timings, and the following is the BEST one

So we were definitely slower with the Surbo fitted by 0.4 of a second

We then did some 0-60 times and the best I got was 9.88 seconds which is about 1.5 seconds slower than usual. To prove this was not a problem with my car we then removed the Surbo and repeated the runs

We couldn't do a 0-60 as my clutch started to slip, but normally my times are around 8.2 (I've done a 7.2 before but never been able to repeat it), but you can see the car performance is definitely better without the Surbo

Also while driving the car, it felt sluggish and restricted with the Surbo fitted, we when up a gentle hill on the motorway that I would normally belt up and I was struggling to keep at 80mph. Not surprising when so much of my intake was blocked off.

So conclusive proof that the Surbo does not add any power and is a large restriction in my car. It may work in cars that have a 50mm inlet (maybe a fiesta 950 etc) but I'm not aware of any car that's that narrow. They should do several in 10mm size increments if they really believe it can work.

About 20 years ago I saw a similar device tried in a rally car (note they are not used on any car today), I've also seen rifling done on intake tubes and the Twister Air filter uses this principle as well. Spinning the incoming air in theory should promote velocity and laminar flow if done well. In this case the air flow is just badly restricted.

Don't buy or touch, this is a scam. I notice the Surbo sales team all have other jobs as main occupations. One of the other Fordmondeo.org members is getting one to test in a near standard 1.8 Mondy. I will post his findings to