Airbox Options

[varnum]

Just got the car home yesterday and need to get it mapped so it will idle when cold and / or when hot!

 

Currently it has a mammoth carbon airbox that fills the boot and I dont want to get it mapped and then do it all again if I change the airbox, so.......

 

What are my options for a non boot flling airbox that is suitable for flowing air for a (currently) 210-ish BHP K series?

 

So far the Auto-Technix (bernard scouse) as i have on my Cat 7 is all I can find. There mst be more options surely?

 

I do know that it will probably affect power and more importantly torque, but this car is supposed to be my Caterhams more practical cousin and it needs to have at least similar boot space to convince my wife of that!

 

TIA

 

Tim

[Martin R]

If it were me, i would remove the airbox and have a look at the trumpet lengths inside. Depending on whats inside you may have to buy trumpets as well as another air box cover.

 

Are the TB,s Jenvey's ? Bernard would be my first port of call as im sure he does a variety of air boxes. Is it an early car ? You may be able to make a seperater to give you a seperate boot.

 

Im not sure who can map a DTA properly after you sort the airbox. I would expect a smaller airbox would make it run richer, so you should be safe to drive it to a mapping session.

[varnum]

Thanks Martin

 

I had reckoned that I might have to buy new trumpets. Didn't get a chance to look in the airbox on Sunday so will do that at the first opportunity.

 

The TB's are QED which I think are badged up Jenveys. Bernard is the obvious option and I have one of his on my Cat, but just wondered if anyone had used an alternative i.e. Reverie, or whether the ones used on the sport 190 are available from anyone?

 

I saw someone (poss Eliseparts?) advertising Bernard Airboxes with a suitably adjusted aluminium boot panel included in the price, but this would require the boot to be cut to a template and mine has already been cut so unlikely to fit.

 

I have spoken to Northampton Motorsport who say they have mapped DTA and have done an Elise previously.

[varnum]

Here is a better pic of the QED carbon airbox fitted to my car. Should i really be considering changing this?

 

[Martin R]

That IMO is utterly ridiculous. I have never seen one that size before. The normal one on an S1 intrudes into the boot space about an inch at most. I cant belive the trumpets are long enough to justify that.

[varnum]

Martin

 

A bit of research suggests that this is a QED made airbox. Still dont know how long the trumpets actually fitted are, but it was developed because QED consistently saw power losses on their tuned K series engines with every airbox solution they tried. It has a specially developed ITG filter in a cylinder shape right across the rear of the box which is what leads to the curved shape and alledgedly gave no power losses at all on any N/A tuned K series - so up to 230-ish bhp I guess. It was listed in their catalogue at around the time that this car had its most significant engine upgrade in 2002. I suspect that it would be great on a race car or serious trackday / sprint car as it also reduces noise which is a factor at a lot of tracks not least at Castle Combe wher this car was regularly used, but it is not ideal on a road car because of the space it consumes.

 

This is the final QED run dyno plot in 2004. A later run in 2007 showed higher peak BHP (214) but for some reason doesnt show torque.

 

[chris_h]

Lol, that's nearly as big as the engine.

[Martin R]

Tim, i have no doubt all that is correct On most K series set up,s the air filter is located next to the left hand air intake at the end of the big intake pipe.

 

I suppose you have a decision to make. Lose the boot space or lose a bit of power and torque and gain a boot.