41 replies to this topic

[yaaan]

I'm currently giving some thought to how I might provide a cooler air flow to my ITBs rather than leaving them sucking on warm engine bay air. I was wondering, if I were to stick some air ducts down in the side vents and given that they would obstruct a large part of the vents, will this have any noticeable detrimental effect on general engine bay cooling? This seems like the easiest solution rather than fitting additional vents elsewhere which would mean cutting holes in the clam somewhere, but would reduce air flow into the engine bay to some extent.

[fezzasus]

Not an issue at all - the original air box ducts air from the vent and doesn't have an impact on cooling

[yaaan]

Yeah I figured that but then thought that the airbox just floats around inside the void behind the vent whereas I was considering some ducts that fit up against the vent so maybe obscuring the top third or so of the vents. I guess it's probably not enough of an obstruction to be an issue but just thought I'd see if there were any obvious reasons not to do it that I hadn't thought of

[Sticky]

Welcome to my world

[yaaan]

I take it you've had some thoughts on this too then I really should stop reading stuff and just be content with what I've got

[FLD]

Roof scoop?

[yaaan]

Would look a bit daft with a soft top I reckon I did consider it but figured I'd have to invest in a hard top or at least a new rollbar cover and that makes it a more expensive option. I also thought about placing vents on the sloping side sections either side of the engine bay (seen them somewhere else before but can't find the picture right now) but this would involve cutting holes in parts of my car and not sure my 'skills' stretch as far as moulding fibreglass.

[badgerade]

I've been thinking about this as well. Could something along these lines work? Not sure what effect this would have on the lovely induction noise, and I guess you'd have to get the box over the trumpets sized correctly.




I think Vocky was running a cold air feed at one point?

[FLD]

Would look a bit daft with a soft top I reckon

Yeah, it might be a bit rubbish. Random idea, have you considered another couple of naca's in the undertray with some ducting? Cold air feed AND less air under the car.

[yaaan]

I've been thinking about this as well. Could something along these lines work? Not sure what effect this would have on the lovely induction noise, and I guess you'd have to get the box over the trumpets sized correctly.




I think Vocky was running a cold air feed at one point?

Ah, somebody already makes one of these. This was going to be phase 2 of the project, seeing if I could get some sort of cover made up and ducting directly from the whatever vent I use to the intake. It would be a shame to muffle the ITBs though

... Random idea, have you considered another couple of naca's in the undertray with some ducting? Cold air feed AND less air under the car.

I was reading about these earlier and never even thought of trying to tap into them. Do you actually get that much air flow though them?

[J4EY D]

I haven't even got mine fitted yet and I'm thinking of how to get them some lovely cold air I was thinking of puting some ducting straight from turbo ears to somewhere near the ITB's, no clue if this would make any difference though...

[badgerade]

Ah, somebody already makes one of these. This was going to be phase 2 of the project, seeing if I could get some sort of cover made up and ducting directly from the whatever vent I use to the intake. It would be a shame to muffle the ITBs though

Yep - if you google 'ITB Plenum' there is whole world of useful/useless info! The main concern seems to be that if you flow the air in from one end, then you'll be starving the cylinder at the opposite end. The solution would be feeding from either the middle (not an option on our cars really) or from either side.

[robin]

could you not run some flexi pipe from each side vent (do you have turbo vents) up to either side of the bodies.

[davemate]

The box looks good, but you really are so limited on space in there when i have seen the conversions. what you really need is to either have a box with twin feeds, or extend the trumpets, or change the angle of them, so that they can be up and out of the engine. Custom box shouldnt be too tricky to make. On my ax, which has twin IDFs, i found that a bonnet scoop really helped, but it was still in the bay, so i extended the trumpets and cut holes in the scoop so they were actually taking in fresh air. this really helped.

[Sticky]

To fit an airbox will reduce the noise but also reduce power as you'll need a big filter on the end (like the SC boys). IIRC Vocky suggests 5-10bhp. I've thought about the NACA idea but there isn't much space underneath the engine, Ducting from turbo (or NA vents) will be a balance between forcing air through some ducting and reducing airflow into the engine bay.

[Sticky]

The box looks good, but you really are so limited on space in there when i have seen the conversions. what you really need is to either have a box with twin feeds, or extend the trumpets, or change the angle of them, so that they can be up and out of the engine. Custom box shouldnt be too tricky to make.

On my ax, which has twin IDFs, i found that a bonnet scoop really helped, but it was still in the bay, so i extended the trumpets and cut holes in the scoop so they were actually taking in fresh air. this really helped.

Vocky has extended his trumpets and had to move the firewall to make them fit.

[davemate]

how detrimental would it be to manufacture curved trumpets, thusly saving removing any strucurap parts of the engine? -the only thing, is that it is pretty dead air by the rear window.... mad as it would look, extend the trumpets, make a new roll bar cover! there was a really interesting article in track driver about induction trumpets.

[slindborg]

Would look a bit daft with a soft top I reckon

Yeah, it might be a bit rubbish. Random idea, have you considered another couple of naca's in the undertray with some ducting? Cold air feed AND less air under the car.

Man up

Edited by slindborg, 29 July 2012 - 10:53 PM.

[davemate]

why not a naca vent either on the rear clam, pushing more towards the engine, or up higher where the fuel filer would be on the other side. i think there are some pics of that somewhere.

[vocky]

I had an airbox fitted to mine, itb noise was very muffled ( it probably would have passed Bedford's strict noise levels), but my engine lost 10bhp at top end of the rev range - so it was removed. Now I have a foam Pipercross filter - rated for 300bhp, rather than the original webcon supplied item - rated at 210bhp I originally had two cold air feeds from the vxT ears, but was not happy with them so took them off. I was planning on replacing them with improved ductwork, but that has not happened yet, however I have mounted the Denso alternator lower down on the engine so I do have the extra room for the bigger ducting. When my new engine goes into my vx I will install some new cold air ducting as well.

Edited by vocky, 30 July 2012 - 07:26 AM.