30 replies to this topic

[Mrstars11]

Hi everyone,
Hope your all ok,

I'm having a bit of a dilemma with my air filter.

I currently have a k&n pancake filter fitted and it sounds nice, and my cars ok for power. Considering its a 998cc.
However ive been informed that because the filter sits directly behind the engine block its probably pulling in warm air, which affects the performance.
I was told using the standard big black plastic air box with a filter in would be better, or even better still, put the plastic box back on and pipe a cone filter to down right behind the grill.
I've also seen people use the box with standard filter in then just duct pipe work to the grill.

Does anyone have any thoughts on this, whats the best option for getting anything extra out the car.

Or just any general advice, ive read a thread on here which was bout filters and power and they found that the standard plastic box with holes drilled was best.
Any input is appreciated.

Dom.

[HarrysMini]

A K&N element in the standard plastic box drilled has proven to be the best for maximum horsepower.

Personally, I think driving is about the experience more than the numbers and I think something that sounds nicer more than makes up for the 1 or 2 extra bhp you might get with a standard drilled box.

Edited by HarrysMini, 13 August 2014 - 05:30 PM.

[coopdog]

cold air feeds dont work unless the air feed atm is very bad

[Mrstars11]

Hmm, my main reasoning for looking into this, was basically we went to mitp this weekend and 4 of us had 998cc minis, mine seemed to be much more sluggish and generally slower than the others, I struggled to keep up at times.

I was thinking of quick fix (cheapish) ways to get a bit more from my engine.
Sucking in cooler air seemed to be one i thought would help....

[jpw1275]

Maybe keep your existing set up and get it serviced and a tune up on a rolling road..... :0) it'll make a world of difference

Cheers james

[Mrstars11]

Maybe keep your existing set up and get it serviced and a tune up on a rolling road..... :0) it'll make a world of difference
Cheers james

Right, a few people have mentioned rolling roads to me now, I think I'll look into it, if I take it to a rolling road place im guessing they can improve the output for me there right? By doing whatever they think? I reckon I'll look into the costs of it.

Thanks.

[HarrysMini]

Getting your car setup properly will have a far greater effect on power output than any air filter will. 

[Quincy Sparks]

Plus 1 on a rolling road set up, made a massive difference to our 998, so much more pull in the lower gears now, but still happy at motorway speed without screaming it's head off :)

Worth seeing if a local club are doing a 'shootout' day near you, could save a few ££? (as long as they're planning to make adjustments rather than just take measurements)

[jpw1275]

Or if your abit strapped for cash try a colour tune and get your mixture somewhere near and a service...:0)... But a rolling road tune up is the way to go

Cheers James

[coopdog]

probably the fact you have a different FD 

[Mrstars11]

Thanks guys, I'll look into local rolling roads.

See where that leads me.

[Ethel]

As Coopdog says not all 998's are equal, even from the factory. There are different compression ratios and different final drives. I'll go against the grain a bit and say a rolling road won't make much difference if your car is near original spec. If it does there's likely some underlying issue that means tuning it to the factory service specs doesn't hold the tune through the revs.

 

I'd look for potential power losses, tyre pressures, tracking, binding brakes.... and plot the centrifugal ignition advance throughout the rev range against the factory figures before forking out for a run on the rollers. You could also check the compression and valve clearances.

[timmy850]

Here is the article written by Keith Calver on the subject. For small bore engines the standard box seems to be the best with a high flowing filter inside and a few speed holes on the correct side of the filter.

 

http://www.minimania...aner_test__1288

 

Have you got a stub stack fitted on your pancake filter at the moment? They have been proven to make a noticeable increase in the flow into the carb (around 5-6% from memory in the Vizard book)

http://www.minispare...N etc/SS51.aspx

[Mrstars11]

Here is the article written by Keith Calver on the subject. For small bore engines the standard box seems to be the best with a high flowing filter inside and a few speed holes on the correct side of the filter.

 

http://www.minimania...aner_test__1288

 

Have you got a stub stack fitted on your pancake filter at the moment? They have been proven to make a noticeable increase in the flow into the carb (around 5-6% from memory in the Vizard book)

http://www.minispare...N etc/SS51.aspx

 

hey timmy,

yeah I read this article about filter choices, this is what lead to my subsequent confusion. I had always assumed I was better off with my pancake filter, it also has a stub stack yes.

 

but from this article I have acquired a filter box and its had a few holes drilled into it anyway. im just debating if id be better off covering the holes, and piping with duct right up behind the grill, so its just the coldest air possible being pushed through the filter box.

[Moggyton]

Definitely get it on a rolling road, i gained 9bhp from a standard 1275! It also makes the power a lot smoother and more useable.