factory pro hayabusa stacks

[glenn71]

I,ve fitted a set of these and they are 46.5mm I.D stock is 49mm long and short.The stack itself may be 60 or so mm but with the rubber boot fitted they are only about 10mm shorter than the longs.Dads bike sounds better with them and says the throttle feels better.Mine are being dynoed and mapped so time will tell if i,ve pissed more money up the wall?

[glenn71]

This factory pro dude talks a big game and bags the shit out of all of his competition.Time will tell if he is full of it himself??you will here about it if his is.The dyno testing is being done on a dynojet 250i with realtime torque readout software.

[GeorgeC]

I'm interested in the results...

I've played with some short billet stacks on my motor and haven't been able to see any real difference, but one thing I haven't done (yet) is try them vs. stockers on the same day at the track.

[glenn71]

They are the real deal from early reports.My dads bike is reporting better fuel economy,better part throttle torque and mid range and a much better sound.My bikes not back from the tuner but he said it runs smoother and wants more fuel up top because of better breathing.Easy to fit too,about an hour or so.So far so good.

[glenn71]

8hp at 8300rpm 5ft/lbs.Not dips below stock stacks anywhere from 1500rpm up.They tail off after 10,000rpm though.Great street stack.

[gnd111]

Do you have any dyno charts you can post?  What box mod / pipe and size motor?  Thanks for the info on this...

[Mr.King]

Wow.....great results.......I use the all short factory stacks with good results......please post a chart so we can check it out.....also...did you try using all factory shorts before trying the velocity stacks?

[glenn71]

my bike is an 04,it has a ti force race system(60mm can).ceramic coated headers,Small airbox mod,custom tuned with pc3usb installed.My dad has an o3 with yosh cams,tiforce sumo system,small airbox mod, pc3 usb custom tuned as well.I want to wait for when he does his for 2 back to back tests on stock cams and mild cam set ups to see what they do.The stacks are only about 20mm off the top of the airbox.I,ve also got to figure out photos onto this forum.i haven,t even picked it up yet and after seeing good gains on the emailed printouts and being flat chat at work,i,ve never been so keen to get on the thing.both dads and my bike have only had the standard stack combo in so far.

[Goo'Roo]

Does the engine sound louder? I'd like to increas that intake growl tipical of big cc engines..

[gnd111]

Does the engine sound louder? I'd like to increas that intake growl tipical of big cc engines..

All short stacks and the large box mod will do that...

[Goo'Roo]

Does the engine sound louder? I'd like to increas that intake growl tipical of big cc engines..

All short stacks and the large box mod will do that...

I'm going that way, except that I need long and short stacks. I need more torque than possible from 4k 'cause of our mountain's roads.

[glenn71]

its sounds REAL angry over 7000 rpm.It has a resonance that seems to give the exhaust system a kind of RRRIIINNNG,abit like a 600 has,but with much more base.

[Goo'Roo]

I bought them

and at the beginning I was thinking to buy even the complete airbox. I haven't found any feedback about that, is it possible??

In Italy is pretty common to project and build new airbox to find more power, I can't understand why it didn't have any success with the busa..

So I've decided first for the small mod, than I think I'll go for the big one with a panel filter and velocity stacks.

[Ksana]

I bought them

and at the beginning I was thinking to buy even the complete airbox. I haven't found any feedback about that, is it possible??

In Italy is pretty common to project and build new airbox to find more power, I can't understand why it didn't have any success with the busa..

So I've decided first for the small mod, than I think I'll go for the big one with a panel filter and velocity stacks.

correct me if I'm wrong

but I thought you couldn't use those ram-air
w/ turn signals

[Goo'Roo]

I don't think I need turn signals to go faster..do you?

[glenn71]

Look up the Australian Hayabusa Club under technical discussion.Their is a topic about the stacks there with dyno printouts posted.Like i said a great street stack.If your bike is regularly over 10K you may want to choose shorter ones.The fuelling feels really smooth.

[Ksana]

I don't think I need turn signals to go faster..do you?

prolly not

I'm going that way, except that I need long and short stacks. I need more torque than possible from 4k 'cause of our mountain's roads.

but after reading ur mtn road post
either you don't have vehicle inspections or this isn't a streetbike

[DarkFalcon]

There are a couple of tuning effects going on in the Busa induction path.........with one dominant one. The math is cumbersome but pretty straightforward, and the FactoryPro 60mm stacks should do pretty much what has been advertised and what is being validated by users. They have been designed around stock camshafts, though, and the results will be highly sensitive to intake camshaft durations. On paper, I think (1) a really interesting combination would be the FactorPro(60mm) on the inside and the stock shorts on the outside for an engine with stock camshafts and (2) all FactoryPro stacks(60mm) with longer duration intake camshafts and a stock ECU. An extended ECU will change the equation completely and move the bias towards shorter stacks. I have ordered a couple of different sets/lengths and will doing some testing soon.

[glenn71]

We should have a dyno printout of the stacks on a busa with yosh cams and ti force sumo in the next few weeks as well.

[Goo'Roo]

but after reading ur mtn road post
either you don't have vehicle inspections or this isn't a streetbike

It is a street bike. I'm doing some open track session just some times. The fact is that in Italy you can't "touch" your bike. You can't do absolutely nothing on your bike..So..when just a different measure of one tyre  brings you to a 500 fine and a vehicle inspection..then just GETAWAY.  It's the only way to survive.

[gnd111]

but after reading ur mtn road post
either you don't have vehicle inspections or this isn't a streetbike

It is a street bike. I'm doing some open track session just some times. The fact is that in Italy you can't "touch" your bike. You can't do absolutely nothing on your bike..So..when just a different measure of one tyre  brings you to a 500 fine and a vehicle inspection..then just GETAWAY.  It's the only way to survive.

Better be careful - those Carabinieri will shoot....

[Goo'Roo]

Just be faster than bullets..

Anyway,is that large mod a succeful mod or not? I live 10 miles from the BMC factory, and they can prepare a custom filter on demand. So would be really easy for me to do it.

I'll have those intake ducts, large mod, velocity stacks,a complete 4-2-1 Muzzy exhaust and a PC3 as first light stage. what do you think?

And maybe this custom end can.. Do you like it?

[gnd111]

 

[Yngve]

I just got mine.

I cont belive they will give more power on my 1585 than all shorts. No way.

Maybye they give better torque on a STOCK or near stock bike but not on a modifyed.

Ill run some dynotest in a month or so on another bike ( 1360, ported head, Yosh cams and Tiforce Sumo exhaust ) but I dont belive thay are the hot tip on that one eiter.

Damn.. Money out of the window..

[Tybalt71]

Im running their recommended street set-up,  2 tall and 2 short.I believe the tall on the outside and the short on the inside, I could be wrong on the combo, but under my set-up that was what was recommended to me and i bought accordingly