Velocity Stack Combinations

[vmaxbaby]

Hello All,

I have a question, our bikes have been setup with 2 short and 2 long velocity stacks to give all around power.  The 2 short tubes are 48mm and the 2 long are 50mm the throttle bodies are 50mm so of course the long tubes match 100%. Now from reading I see that replaceing the 2 long with 2 short (now all are short) will give you more peak power.  Not sure what RPM or Speed is peak power but that is the claim.  Also found a place that sell all 4 short at 50mm but with a price of $ 200.00, and of course they claim it flows allot better air.   With the modifed air box it seems to go hand and hand BUT.. has anyone done this either all 4 short or all 4 long and what is the results.  To purchase 2 short factory the cost is 24.95 and suppose to give 3HP just not sure where you lose the power using 4 short.  Need someone that knows more about the physics of our engine than what I know

? After all the engine is just a big air pump get more in get more out makes more power.
Any feedback would be great.

Thanks,

Vmaxbaby
http://www.flairphoto.com/busa.htm



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[AZIROC]

i bought 2 short stacks off someoen off of here and put them on my bike (aka i have 4 short stacks on). personally, i dont feel a SOYP improvment, but i do notice up top she seems to go a bit "quicker".

 

[Bugsy]

Any engine mods ?

 

[Mr Brown]

Tall stacks provide more bottom end, shorties more top end. Theoretically you can gain 1-2 hp with all shorts, but I doubt it would be noticeable.

 

[PaceMaster]

Thanks Mr Brown-- I was wondering too about that mod.

 

[mountainmotor]

Hello All,

I have a question, our bikes have been setup with 2 short and 2 long velocity stacks to give all around power.  

I think Suzuki went that way to reduce the intake pulses created by the larger displacement cylinders to help smooth mid-range power delivery .


When the 2001 GSXR 1k came out, the throttle bodies and head were the same as on the 750 . The only difference was ,  four 5 x 15mm slots was built into the base of each velocity stack used in the 1k engine. The slots reduce intake pulses created by the larger displacement cylinders to help smooth mid-range power delivery and I believe the small loss in low and midrange we see when using all Busa short stacks is from these type not having the slots thus suffering from said intake pulses inside the airbox and having these slots is no big deal since they are inside a pressurized air box compared to a bike w/o ram air in which the slots would not be desirable .

If a guy had the time and desire all he would need do is try all short Busa stacks and the slotted Gixxer stacks back to back on street and dyno .

It might take out the torque spike we see in the dyno sheets as well .

One German tuner in particular uses the 750 stacks when he builds performance Busa's.

 

[vmaxbaby]

I talked to my tuner today and he agrees with the all 4 short stacks for high end power. Meaning he would recommend for 1/4 mile and for track day because you are running red line every gear and want the power top end. He went on to say that putting all 4 long would give mid range grunt for street use. In the past working on R1's / GSXR 1000's he noticed it mid-range. What he told me was you have to have a trade off, you do get a few hp (3 to 5) so the quesiton is where do you want it, top end or mid range because with the stacks you can't have both unless you keep it stock 2 short 2 tall than that is the best of both but you can fine tune by switching out. I will cal Schnitz Racing tomorrow and talk to one of there techs about this same subject matter. Meanwhile click on the link below to read about the short stacks just remember all 4 short put the power up high and will take some away down low according to the article. You can get 2 more long stacks for around $ 25.00 which if it does work like it is being told to me $ 25.00 for 3 to 5 hp is well well worth it. Check back tomorrow to see what I find out.



Vmaxbaby

 

[nolo263]

the ones from schnitz racing look nice and they seem like they should give you more power. i would like to see someone dyno with them or run at the track and see if they make a difference.

 

[vmaxbaby]

I called today but the person I was told I need to talk to is at a race and to call back on Tuesday so I guess I call back on tuesday to talk about having 4 long instead of 4 short. I did call another bike shop today and they switched me to there mechanic (know nothing about his skill level) but anyone ask him about the 2 long vs short and he said that when he raced he always had 2 sets one set of shorts for 1/4mile and I set of long for street riding. So I ask the question has anyone done the 4 long and what was the results.

Thanks,

Bill

 

[fstAZfk]

 

[CASH$$$$]

i got 2hp outta my all short stacks...

 

[sully]

i got 2hp outta my all short stacks...

are they aftermarket or the factory stacks?

 

[frisbee]

I got some stacks off e-bay for $10 so I can have all short on mine .

 

[Johnnycheese]

the problem with all short is the double dip in HP and Torque.
keep the stock mixed even on big motors.
and if you want all short just order them from Suzuki a lot cheaper

 

[huntn4heatrs]

Tall stacks provide more bottom end, shorties more top end. Theoretically you can gain 1-2 hp with all shorts, but I doubt it would be noticeable.

+1 Also, all shorts with a cam upgrade.

 

[sully]

I was going to do this but have decided not to. My tuner explained it like this: Yes you will gain a little up top (1 or 2 HP) but you will loose it in the lower RPM's. Gains will not be worth the loss. I trust him since he brought my bike back to life after another shop killed her. If it sounds too good to be true then it prob is.

 

[Kogeltje]

Bring this topic back to life.....

I found some 4 all long Factory Pro stacks at a mate of mine who sold his busa.
He said i could have them for free, they cost 220 online.
So i thought i'd go and see what difference it makes.
With stock stacks the bike made 180hp on the wheel.
Tomorrow im going to the dyno to see if they make some more or less at the power line.

 

[Kogeltje]

Dyno results today;

Before : 173,5 pk @ 9312 rpm en 145,1 Nm @ 6112 rpm
After. : 179,5 pk @ 9384 rpm en 148,6 Nm @ 6014 rpm

 

[cwalker2]

Nice results!