I have a Triumph Spitfire w/Hayabusa:
https://www.flickr.com/photos/bb-kristinsson/26987947322/in/album-72157668450434305/

- First I modified the Hayabusa std airbox (made it a bit lower, as many have done) w/K/N and feeded a tube in to the front grill.
- Then I did this change, using the PX500. (Thought I would get more power, and great noice , made a hole in the bonnet and the air filter sticking a little bit out.

Maybe the airbox is better? Maybe the PX500 is better? But I am sure that after 100 mph the Pipercross is not feeding enough air to the engine. Which is why I was going for the Scoop...

If any of you have knowledge of what is better PLS FEEL FREE to give me some good advice !
THANKS

https://www.flickr.com/photos/bb-kristinsson/26987947 322/in/album-72157668450434305/

I would have to agree that pipercross restricts air flow had mine RR witout a filter on it couldn't stand the stench of fuel vapour so put my piper air filter back on and the reduction in power was very apparent so binned it and don't run with air filter now I just don't go near a naked flame after I have driven the kit

I would off thought that the optimum is the OEM airbox with cold unrestricted air supply.

Of course OEM expect a rounded noise vs cost vs torque vs power vs space compromise but it should provide a good set up.

I am actually looking to get an airbox fitted and ditch my px600 filter that pokes through the bonnet. The noise is quite excessive. It will be fed with cold air and i expect the power to be similar.

As mentioned before, for max power run no filter at all. We all know the potential problems with this though!

quote:

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Originally posted by bi22le
I would off thought that the optimum is the OEM airbox with cold unrestricted air supply.

Of course OEM expect a rounded noise vs cost vs torque vs power vs space compromise but it should provide a good set up.

I am actually looking to get an airbox fitted and ditch my px600 filter that pokes through the bonnet. The noise is quite excessive. It will be fed with cold air and i expect the power to be similar.

As mentioned before, for max power run no filter at all. We all know the potential problems with this though!

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px500 is a bit small really, moving to a px600 made a few hp difference on our old car.

GSXR1000 experience in a Westfield. Same engine architecture, but smaller.

PX600 was superb, the best power output on the dyno, the best times on the track. Mapped with a PCIII, nothing fancy. Main difference to you (and the essential one I guess) is that the PX600 fitted under the Megabusa (V8) bonnet, with the air intake of said bonnet feeding nicely. All covered up, but still incredibly noisy (static dB OK, but driveby marginal). Without the bonnet on, it was well into the ear's threshold of pain, unimaginable.

Suzuki airbox wasn't as good, dyno or track, regardless of various ducting to try and get air into it. It was also a nightmare to fit, although the airbox is shallower than most, it still had to stick out of the bonnet. Really, really quiet though.

I thought a PX500 was too small for the 1000cc. I have no evidence to support this thinking though.

In theory an airbox will almost always be better (as long as its well designed at least - remember the bike OE box is meant to work with the OE exhaust too also it won't necessarily be designed to give you the torque / power in the places you want it)

The volume can be tuned to optimize your torque curve and the intake / filter can often be positioned in a better location too

Of course there are so many interrelated variables in this - so a sausage filter can just be the easy option
(I've got my ITG jc40 ready to fit to my carbs )




Running without a filter will no doubt give you more on the dyno (were aerodynamics don't really come into it), but not necessarily any significant gains in real driving. (Bare in mind that any changes to the intake setup will need a retune to get the most out of them)

The big problem with running without a filter is how much it will reduce the life of your engine - I remember reading about the testing that david vizard did without filters - he reckoned that after a very short time on the track the dust, grit, rubber that got sucked in bad made some very effective grinding paste inside the engine



[Edited on 13/6/2016 by mcerd1]

[Edited on 13/6/2016 by mcerd1]

The black top that I run in my single seater hill climb cars runs PX500 filter. It made 156 on the rollers with the only mods being the addition of R1 carbs on a DanSt manifold. I also run the original rubber trumpets as fitted on the bikes as I was informed that they run far better with these as opposed to metal trumpets. Does any-one have an opinion on the fitting on these to the Zetec...

quote:

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Originally posted by motorcycle_mayhem
GSXR1000 experience in a Westfield. Same engine architecture, but smaller.

PX600 was superb, the best power output on the dyno, the best times on the track. Mapped with a PCIII, nothing fancy. Main difference to you (and the essential one I guess) is that the PX600 fitted under the Megabusa (V8) bonnet, with the air intake of said bonnet feeding nicely. All covered up, but still incredibly noisy (static dB OK, but driveby marginal). Without the bonnet on, it was well into the ear's threshold of pain, unimaginable.

Suzuki airbox wasn't as good, dyno or track, regardless of various ducting to try and get air into it. It was also a nightmare to fit, although the airbox is shallower than most, it still had to stick out of the bonnet. Really, really quiet though.

I thought a PX500 was too small for the 1000cc. I have no evidence to support this thinking though.

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To reiterate, this is a GSXR1000, so your mileage will vary.

So many variables, in fact, that it's impossible to state what will work 'better' than anything else. Everything is a compromise.

My compromises were that I wanted the filter assembly to fit neatly under the superb Westfield bonnet scoop, that precluded the standard airbox assembly. I was therefore willing to accept any slight loss performance, etc., to retain that completely covered arrangement. The big trade-off was noise, it came close to being unacceptable in competition on the drive-by noise metering.

If I was to build/race another, I'd look at the Pipercross airbox, ducted.

I did confirm that the filter wasn't causing any static power loss issues, with a back-to-back comparison with the standard airbox on the rolling road. There was no detriment. Wonderfully quiet though, lovely.

Please note: This is an early engine (K1-K6) arrangement, later engines (and particularly some Honda's I've seen) have the airbox as an injector assembly too. This looks very intrinsic to the package and something I'd not want to dispense with. I'd have to work at retaining it (however tall).

[Edited on 14/6/16 by motorcycle_mayhem]

quote:

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Originally posted by motorcycle_mayhem
To reiterate, this is a GSXR1000, so your mileage will vary.

So many variables, in fact, that it's impossible to state what will work 'better' than anything else. Everything is a compromise.

My compromises were that I wanted the filter assembly to fit neatly under the superb Westfield bonnet scoop, that precluded the standard airbox assembly. I was therefore willing to accept any slight loss performance, etc., to retain that completely covered arrangement. The big trade-off was noise, it came close to being unacceptable in competition on the drive-by noise metering.

If I was to build/race another, I'd look at the Pipercross airbox, ducted.

I did confirm that the filter wasn't causing any static power loss issues, with a back-to-back comparison with the standard airbox on the rolling road. There was no detriment. Wonderfully quiet though, lovely.

Please note: This is an early engine (K1-K6) arrangement, later engines (and particularly some Honda's I've seen) have the airbox as an injector assembly too. This looks very intrinsic to the package and something I'd not want to dispense with. I'd have to work at retaining it (however tall).

[Edited on 14/6/16 by motorcycle_mayhem]

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