Both dad and i have fitted these.Dad is just riding his and mine is currently being mapped.These are no gimmick.Early reports from dad are better fuel consumption,better part throttle and mid range torque,and a much better sound.Early reports from my tuner are smoother running and a step forward in breathing needing more fuel.I,m itching to see and feel the results as i,ve heard most don,t work.
spamanglenn squeezing blood out of a stone as usual. Cheers,
Kawasuki<i>Edited by: kawasuki at: 27/1/07 10:21
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Quote:as i,ve heard most don,t work
I've heard the same thing Bruce
N2O no laughing matter
f*** nos I've got Velocity
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I believe the factory stacks don't flow well, there is suposed to be a lip or something that chokes airflow up a bit. Aftermarket ones are suposed to be smooth and flow better. From reading the service manual, I was of th opinion that the shorter/longer velocity stacks resulted in substantially different fuelling requirements and one reason why the inner and outer cylinder pairs were served by a differet map. The other reason, I think, is due to cooling? Then again, if you have gutted the airbox and changed pipe, the mapping is not as Suzuki had intended either(rememer the flapper). I guess that in order to get the most out of the trumpet change, you need to have the ability to at least trim fuelling for inner and outer cyliner pairs ie PCIII I guess can do that and dyno time with EGT probes on each header to balance things out?
Bring on the dyno graphs and silence the naysayers. <i></i>
Don,t use soft track tyres for dyno work.The old pirelli supercorsa turned to jelly and ended up 8hp down on before the stacks were fitted(no the back isn,t strapped).An 020 has been fitted and will tell the true story good or bad on monday.I just hope the tyres the problem or i would have learnt an expensive lesson(never trust american marketing).Dads out riding his in bathurst and liking it,i haven,t even heard mine,and i,m being told on one hand the bike wants more fuel up top(assuming better breathing) feels REAL smooth on the throttle but makes 8hp less.Unfortunately what i,m hearing sounds like the symptoms of when you choke an engine and fit a smaller carby.The stock stacks are 49mm ID,these are 46mmID.Interestingly the ti force 60mm in/out can made 1 hp less from 7000rpm up than the 60mm in/48mm out can.Go figure,velocity wins over flow on the exhaust,yet perhaps the opposite is true on the intake? <i></i>
I've had reworked factory shorts on my bus for years.
The theory is that all longs give more mid range & all shorts better top end or vice versa depending on what article you read.
I've tried both ways.............didn't seem to make any difference
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I suppose you can,t make a circle more round?Perhaps we have found one area suzuki did a good job on? Even if it made the same power i wouldn,t be able to sell them,so i would still leave them in for the sound,but not for 8hp less,24hrs to the answer. Glenn the Spa Man<i></i>
Glenn, apparently Suzuki have not done a good job! from memory there is supposed to be inteference where the rubber horns join the alloy throttle bodies or somewhere nearby. Anyway it does not help their flowing properties and this is where aftermarkets should help. Inlet tracts need to be smooth with no steps ie no instant diameter changes eg where parts join. As 01 mentioned shorter stacks work at higher rpm so replacing the longs with shorts should sacrifice a little midrange and gain a little top end, in theory. How much is a little, I don't know, it might just be a less steep drop off from peak power rpm. Without individual cylinder pair remapping, I wouldn't be suprised if less or no peak power was observed as I'm sure the fuelling requirements will change and the mapping will be off on the changed cylinders concerned. <i></i>
Interesting point to consider.My tuner uses a sniffer thats about 1200mm long.If i pulled the can and mid pipe i reckon he could get it up each primary and check the mapping on each cylinder with the now all equal length stacks.saves having to weld a bung on each cylinder.Then once their even the exhaust can be refitted for fine tuning?? <i></i>
Another way that leaves the pipe intact which would be prefered, is to measure exhaust temperature at each header and adjust so that all are equal, a bit like syncing butterflies but needs to be carried out at various load and rpm. Externally mounted contact thermocouples can be used but need time to equlize as the header needs time to change temp. The exhaust probe/sensor checks that the overall mixture is consistent. Would take a lot of dyno time to set up though. The stacks are the hardware, the map is the software to run them. <i></i>
A good tyre helps.Ended with just over 170hp sae but picked up 8hp at 8300 and about 5ft/lbs torque.Didn,t lose power anywhere and was better from 1500rpm up.It was better or the same but never worse.Part throttle torque feel is better and smoother apparently.Dave is currently doing 2,5 and 10% throttle runs to get consisitent tre air fuel differences.In summary they take about an hr to fit cost a bit and feel better straight away and benefit from mapping to suit. <i></i>
Good stuff guys, I have been thinking about playing around with my stacks for sometime, but what ever I do it need a decent tune up at the end of the day, I have been thinking of setting up a set somewhere halfway between the long and short, Ill pop into Metro's when I get a chance and track down some stacks..
or ps Glen can I grap your old stacks if tour not using them, if I work it out I'll put you into partership with me with Busa Stacks Are Us
Cheers Robert
Aren't all Busas Copper & Plated, the others are just all very poor slow ugly copies !!!!!<i></i>
I,d sooner do you a good price on the factory pros.If your going to spend good money on a tune,at least put something on that gives a decent improvement.Shorter stockies will help up top but leave a bit of a torque hole, and still flow like STOCK stacks.Dave was saying torque improvements are realised down as low as 1500rpm on light throttle with these things.Shnitz do a long and short street combo or all shorts for racing as well.You can try my 2 shorts with your shorts,then try these afterwards.Dads is unmapped to suit and he is pretty happy.If a 350kg bike/rider combo can notice a difference,they can,t be half bad. <i></i>
Simmo i will sell u my rubber stacks $400 Excellent cond. Alos got that header pipe, were will i send it? Cheers,
Kawasuki<i></i>
Seems Suzuki couldn't decide whether they wanted the busa engine to have more torque or outright power characteristics........so they had a bob each way....2 short, 2 long
MV Agusta have variable length intakes like just my old 93 Mazda MX6 V6
They'll catch up one of these days...then look out <i></i>
Ray I'll give you a call later sold
Cheers Robert
Aren't all Busas Copper & Plated, the others are just all very poor slow ugly copies !!!!!<i></i>
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