stage 3 air box mods

veefer800canuck posted this a while back
it is back to back dyno runs, with and with out the snorkel
basically no surprises here. no massive gains, no losses. just an average of a half a horsepower almost everywhere. and a few spots with 1 hp. not really any losses anywhere.
this is what im getting at. opening the airbox wont hurt anything, you wont get massive gains or anything, but it helps a little, and this is untuned, so if you map your power commander for this it will help even more. and im sure with a full exhaust and a tune to support opening the box further, you could see like maybe 1 or 2 hp, which i would gladly take.


From: DynoWorks@aol.com [mailtoynoWorks@aol.com]
Sent: Monday, 29 March 1999 5:20 PM
To: vfr@cs.wisc.edu
Subject: 800 snorkel dyno test (mostly data)


Hello list ...

Had the opportunity to do a back to back dyno test on the VFR800. We'll let
the numbers tell the story.

Dynojet Model 150 Chassis Dynamometer
Eastside Harley Davidson, Bellevue, Washington
DYNORUN #1, baseline, 4th gear roll-on - 3-27-99, 3:17PM
DYNORUN #5, no snorkel, 4th gear roll-on - 3-27-99, 3:22PM

DYNORUN #1 DYNORUN #5
RPM SAE hp SAE hp
3500 28.3 28.8
4000 32.1 31.7
4500 35.4 35.4
5000 39.8 40.3
5500 45.2 46.1
6000 54.4 55.3
6500 62.6 63.2
7000 69.6 69.9
7500 75.6 75.5
8000 81.1 information not available
8500 86.6 87.1
9000 90.0 91.0
9500 91.6 92.7
10000 93.2 93.8
10500 92.9 94.2
11000 90.3 91.6
11500 88.8 89.6

Magnifying the resolution of the 500 rpms nearest the hp peak follows

10000 93.2 93.8
10100 93.4 94.1
10200 93.5 94.3
10300 93.6 94.6
10400 93.3 94.6
10500 92.9 94.2

Magnifying the resolution of the 1000 rpm range nearest torque peak follows

RPM SAE ft-lb SAE ft-lb
8100 53.4 53.3
8200 53.4 53.4
8300 53.6 53.6
8400 53.6 53.7
8500 53.5 53.8
8600 53.4 53.8
8700 53.2 53.7
8800 53.0 53.6
8900 52.8 53.4
9000 52.5 53.1

Testing conditions: 29.66 in.Hg. absolute barometric pressure, Vapor
pressure .44 in. hg., ambient air temperature 49.5 deg. F. Partly cloudy.
All stock '98VFR800FI, 3,273 miles.

Subjective comment: Noticeably louder intake noise. Doesn't sound like a
sewing machine anymore. Changes the character of the engine. Feels raw,
sharper edged. I will be leaving the snorkel out for now.

Wayne Chan, WMRRA/OMRRA #326

 

My main experience with tuning a bike was on my 2000 Bandit 1200. With a stage 2 (no airbox, 2 oval K&N filters on the carbs) a slip on, a Dale Walker jet kit and 5 degree advancer it was not uncommon to see a 15-20 HP jump and a 10 ft/lb jump. Why would this not be the case for the VFR with equivalent tuning using a power commander? Is it already that much further along in its state of tune? Granted, the Bandit was about 400cc's bigger than the VFR so at 95 HP stock it was definitely being held back.

Hope this does not come off as trying to stir shit. I am just trying to learn more here.

 

damn, you are going to fight this to the death huh? lol

 

oh this shit shows been stired since the first winter that man and motorcycle were forced to coexist.

 

i for one know that there isnt really any major power to be had with just a pc and a custom tune (a horse power or 2). but there is a much more driveable and usable motorcycle and powerband to be had with a proper tune. i think you are giving the honda engineers (the ones that made our electrical system, stators, rr's, 30 amp fuse holders, blue connections', conections between the rr and stator after all) way too much credit. i believe they designed the air box with more concern of noise regulations than out right power. this is a sport TOURING bike with emphasis on the TOURING after all. more thought was put into making it a quiet, civilized bike than out right performance. but i will agree with you that the factory air box really isnt holding back the factory bike. there really isnt any power to be had, modifying the air box and nothing else, but that is not MY goal. if you were to put a motad header, a two brothers exhaust, a piper cross filter, velocity stacks, (this is where my modification list stands now) and a rapid bike module with proper dyno tune, then yes i believe that the snorkel and flapper WOULD in fact be holding back power.

i do not view the air box as a end all be all mod, but i do believe that all mods work together and build on top of each other. i do plan on eventually getting the heads ported polished and milled, and fitted with custom cams. and at this point the factory air would, with out doubt, be holding the engine back.

but with a factory fresh, stock bike, removing the snorkel and flapper does little more than make more noise (beautiful loud powerful deep noise), remove a pound or so of weight and clutter, and simplify an overly complicated overly engineered bike just a tad. which i would gladly take along with my 1/2 hp margin of error.

 

so with all this thought of all the engineering that went into the factory airbox to manage the flow to the cylinders, and pressure/vacumme, and the sound waves and resonance frequencies etc; what exactly do you expect or would you expect to happen when someone "fucks their airbox"?

 

those are the two most irrelevant videos that ive ever seen.
what is the one on top based on a twin turbo v8? and the one on the bottom an inline four with a single common throttle body?
i feel as though you are just throwing around a bunch of random links and videos with tons of technology and research in them, regarding induction principles, to make it look like there is tons of research and technology supporting your arguments, but they have nothing to do with our bikes.

 

That's a Formula SAE car! that is almost an exact copy of our Formula SAE car at UCF!
Are you involved in Formula SAE too?

 

though i still dont see where you are going with this...
that intake manifold (and complete lack of an air box) is a complete abomination of what the factory engineers designed. (more than likely suzuki, as running cbr600rr engines is much more cost prohibitive vs the gsxr600 engines). due to the sae rules and regulations the engine must breathe through a single 20 mm throttle body. as a result, they run horrible (but do sound amazing) and only put down give or take 70 rwhp as apposed to a factory gixxer 600 putting down 100ish hp. the 450cc motocross engined formula cars actually do much better than ours on tight technical courses but are completely out of our budget.

 

dont it will run awful, kill your power band, and kill power everywhere.
there is way too much overlap in our cams for a combined manifold to deal with.