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MG MGF Technical - Side air intakes/scoops

I have an early 96MGF with normal side air intakes. In an earlier thread I enquired about using a K&N 57i cone filter with an old Rover airbox the installation of which is very clearly shown on Rob's site. There is also on Rob's site a feature about perspex/polycarbonate side air scoops made by Carl of Sweden. I was wondering whether if fitted, one of these articles would boost the cold air intake to the K&N rather than depending on the suction from the manifold via the normal intake as Rob's pictures show? In the event that it might be an improvement are these scoops still available and how can they be aquired?
Geoff Smart

only recently a chap was making them and selling them on Ebay.
David Clelland

Geoff
I,ve bought the ones off ebay and they are a good piece of kit.
I,ve got the k&n filter and enclosed it in a home made box which was dead easy to do and cost about £4.00 to do.
I fed the pipe down to the passenger intake with the scoop fitted.
When you rev the engine you can clearly hear the suction from the air intake (with a mate,s ears or you revving !)
I think they are well worth the trouble to fit.
The only improvement i should have done was to still keep the pipe as k & n designed (just one) under the car and used the side intake as a "extra" source of air ..ie my enclosed box would then have two pipes feeding it. I,ve seen this done on a web site somewhere.Also have the pipe to the side intake larger than the one which comes with the k&n.
Mel.
m e johnson

some still on ebay ...item no. 150087951304
Mel.
m e johnson

Thanks for your help Mel. Much appreciated!
Geoff. S.
Geoff Smart

I've been thinking about this cool air supply business as well. What I thought I might investigate was whether a single scoop on the left hand side would create enough inflow of fresh air to make a difference. I've got an outside temperature sensor I could reposition at the existing air cleaner intake and mock up a scoop. I could then compare temperatures with & without over the same stretch of road. Has anyone tried this?
M Cunningham 1

<chuckle> I bought a pair of those scoops off eBay last week - and intend to do a little experimenting... I think that I may look to reprofile the edges as well, and might consider mounting it outboard a little further (the scoop is about 25mm above the deck-height).

Gel coat has a reasonable finish. Shame mine were chipped in the post. But since I will more than likely spray them BRG, I'm not too concerned about that right now.

So how much of an improvement? Good question. Carl's mod certainly works. This one ought to too. I was thinking of measuring the vacuum pressure in the air box at speed as a comparative - but your suggestion Mike of measuring temperatures has been done; Graeme Bishko did something similar with the K&N 57i Kit when it came out to show that the ducts did the job they're supposed to. It would also be useful in determining whether these scoops work too. :o)
Rob Bell

I'd be unconvinced by the scoops. the air is particularly clean by the vents on the sides, this is why it's a good location to get your air from using enclosed systems (ITG etc) i doubt you'd see any ram-air type effect for these systems. so probaly not a great idea.
As for other K&N type systems, it'd be intresting to see if the side scoop stirrs up as much air as using Tom's bracket did? all the aim of both to do is to cool the ambient air in the engine bay...
Kingsley

Carl's original side scoops and the K&N pipes both direct cold air into the engine compartment and assume it will find its way into the engine. This might be true at speed, but is certainly not so below 25mph, (ie speed at which the engine demands air through a K&N when revving).

The only way to ensure cold air goes to the engine is to use a fully enclosed system. I'd be interested in knowing whether a shaped air scoop does actually increase the pressure in the ducting, but again I really can't see this having much effact until the car is on the move anyway.

I suspect the problem with vacuummeasurement is looking for a small difference between two large numbers, so a couple of readings on one car would not be statistically valid. I guess the only way to find this out would be to try it!

Chris
Chris

The first thing to remember is that any 'ram' air effect from a scoop will be tiny at any speed that an MGF is likely to achieve. This is why ramjets tend to be supersonic. But, if the outside air simply goes past the side intakes and there is not much flow going through the engine compartment, a scoop could cause fresh to enter and generate a greater flow. This would have a much more significant effect on the air temperature, and it's the temperature which affects the density. It might therefore be well worth while with not very much effort to add a scoop and perhaps apply some insulation to the airbox to minimise further heating.
If you see me making a number of runs along the M74 from Hamilton to Canderside Toll with some duct tape on the car, you'll know what I'm doing ;-)
M Cunningham 1

Hi Mike. I gather that doodlebugs used ramjet engines and none of us are going to achieve that speed. As you know I've got the air box and the K&N and have now some plastic rain water goods to merge two cold air induction pipes into one and then into the air box. One from the near side air intake (hence the query re scoops) and the other from under the car as is the usual route for K&N's. I am going to wait with interest to hear what your duct tape etc. achieves even if it is'nt supersonic!
Geoff.S.
Geoff Smart

Hey, Kingsley, how are you doing? Long time no hear! How's the car? The last time I saw it at Techspeed, it was looking a little sorry for itself?

Regarding the scoop concept - both Carl and I have fully enclosed K&N intake systems (both are DIY too - but achieved in different ways! LOL)

The 'ram air' effect isn't being used in the true 'aeronautical' use of the word, but rather in a lay-man's understanding of things - Carl's scoops do seem to significantly increase engine compartment pressure, as he mentioned way back when...

>>
Posted 26 May 2001 at 12:06:56 UK time
Carl, Sweden

Hi all,
Thursday and Friday was a annual track day meeting over here to find out what the wintertime fiddling with the "F" had done to the car. A few things might be worth mentioning here ...

1. The air-scoopes works wonders, both the one pressuring the airfilter box and the one on the other side for engine bay cooling. Any drawbacks ? Well, the rear lid lock had to be adjusted as the total pressure made the lid open twice !
<<

I don't yet know whether the eBay scoop will be as effective as this - a little testing should be revealing... Perhaps a scoop height of rather more than 25mm is needed for optimum performance?
Rob Bell

First report on temperatures - I've positioned my outside air temperature sensor in the mouth of the standard air inlet duct ( right in the middle of the back of the engine compartment. In an ambient temperature of 16.7°, after about 10 minutes idling, I was registering an inlet air temp of 30°! Just over 2 weeks to May 1st when I can try it on the road :-(
M Cunningham 1

Interesting - look forward to hearing more soon Mike!
Rob Bell

Rob - watch this space - I'm interested too!
M Cunningham 1

Just been out for my first run of 2007 (at last!), so first report on air temperature at the engine intake.
Outside air temperature 18-19 deg, intake temperature 30-35 deg. That works out at about 5% lower air density going in than if the intake was in fresh air. Could be worth up to 5% more oomph! Interestingly, the temperature varied a bit independently of how hard I was pedalling. There was a fair breeze blowing, and I got a feeling that it was having an effect - a bit hotter when on the starboard beam than as a head wind.
Going to investigate the 'military' roads between Loch Lomond and Coulport tomorrow, so I'll see how it goes with some mixed driving.
M Cunningham 1

Is this with an air scoop fitted Mike?
Rob Bell

No, bog standard set-up. On the day out, I was getting more like 35-40 deg without pushing the car at all.
M Cunningham 1

Hi
Two of us have the KN system with 80ml air intake to the filter. One has a heat shield and the other, mine, does not. Both have airscoops and they appear to work well.
Qustion. We cannot get Rover airboxes over here - tried but all been ditched. So to the question K&N make an enclosed system known as the Apollo - has anyone explored the use of this model on the "F"?
David
David Richards

That ought to work well (http://www.knfilters.com/universal/apollo.htm) - how much?

Although we often use Rover 820 airboxes, any cylindrical airbox will do... Fiat is a good alternative in Europe - and perhaps there is a good Japanese alternative in your part of the world David?
Rob Bell

Thanks Rob - will check it out and come back to you


David
David Richards

This thread was discussed between 09/04/2007 and 07/05/2007

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