Need advice for air intakes on mk1

[mowe1979]

Hello all, I have recently purchase a modified mk1b, which I am planning on tidying up,and bit and having a a road/track toy. The advice I would like help on is whether the additional air scoop is doing much (ducted into the boot, holes cut in the boot/engine fire wall, to supply individual throttle bodies) and whether anyone has ago old ideas to make it work better (was thinking plenum?) and look more stock?

Did think about one of Mr Woods vented bonnet lid, but I'm presuming it mainly increases airflow up and over the engine, rather than possibly supplying my air filter?

Will post a couple pictures, once I can get them uploaded.

[Paul Woods]

Hi, the factory air ducting won't add anything to your build by ducting it to the throttle bodies. The reason for this is the huge amount of airflow there already is coming up through the engine bay from the road, which negates any scooped air from the sides or top, you can see this in action by leaving your engine lid unlatched and drive the car at 70mph, the engine lid will lift up and float in mid air due to the high volume of air coming upwards.

This makes all sidescoops and roof scoops pretty pointless, you've heard the expression "pissing in the wind", well it applies here too :)

My engine lid will also do nothing to improve your airflow, that is just a good way to keep water off the engine and allows under lid fans to be fitted for stationary traffic conditions in summer etc.

I would say your best bet is to just leave the throttle bodies open to the current airflow there is in the bay, it really isn't going to get any more flow than that.

[mowe1979]

Thanks Paul, that's kinda what I though but wanted some confirmation before I'm try something else.

As an update here is what I have at the moment, there are holes cut into the boot fire wall just behind the air filter shown. As said, not sure they help much.

Attachment 3166

[Paul Woods]

I would actually block them off, they will be causing drag. Some people have done huge boot mount intercoolers and left big holes in the firewall to aid cooling, problem is it then turns the boot space into a big parachute at speed :)

Nice looking setup you have there, i personally would leave it as it is.

[mowe1979]

The guy I brought it off did include a panel to weld in and fill the holes. I think I will temp block them off, get it rolling road tuned and drive it for a bit. See how it goes.

Then get rid of the additional side scoop, which I'm not keen on (can't upload a picture, but it looks very stuck on!)

Thanks for the advice, really helpful

[Chaos19810]

I can’t remember what the standard air intake looks like it been so long since I’ve seen it but I’ve stolen the idea of a sealed TOMS unit from the sw20 and built something similar for the AW11 using a woodsport snorkel as the starting point it is completely sealed other than a small drain hole of about 4-5 mm to let any rain that might get in escape.

It might be completely useless but it’s just a thought.