Velocity Stacks

I've made 2 different versions of the bracket, one for the 08 - 10 bikes and one for the Evo/796 models. This is because the 08 - 10 bikes use a 9mm(?) idle filter vs the 15mm on the Evo/796. Both of the files can be found in this folder (in STL format, can't do any others right now as I'm at work and only have my STLs on my USB): https://drive.google.com/open?id=18Cv69IQMc0NzhE-TICFth2a-2FAsUYud

The one titled "Bracket for Evo" is for Evo/796
The one titled "Bracket pjgoose" is for the 08 - 10 bikes

The bracket was designed to accommodate filters with a 50mm base diameter (https://www.ebay.co.uk/itm/330803496881) and the filters to be attached to the pipes using straight pipe fittings ( https://www.ebay.co.uk/itm/290649270384 ) going through the respective holes in the bracket.

 

You can purchase them from www.outerwears.com. You can find the correct pre-filter for your filter by using the "search by size" function. I've put in the values I believe are the closest to your Ramair filters and got this: https://www.outerwears.com/proddetail.asp?prod=8932

It's probably best that you double check the filters dimensions yourself to be sure.

 

So I sucessfully managed to print a stack in ABS today, it came out almost perfect (i'm especially happy with groove for the intake pipe fitting) other than the filter stop part which decided not to stick to the support (shown in 3rd pic) and as a result warped upwards. There's also a few small dots of over-extruded plastic on the inside surface, fortunately I should manage to fix these easily by adjusting the printers settings. I shall make a second attempt on either Sunday night or Monday.

 

I'm honestly not sure which is the best, I know that TPO claim that their Beast-R stacks (what my stacks took "inspiration" from) provide a increase in horsepower everywhere;

"TPO BEAST-R Air Intake, with its special velocity stacks and matched K&N conical filters, can flow 18% more air than the stock intake with NO FILTER and NO AIRBOX LID at all! This translates into power gains across the board: The BEAST-R kit provides more horsepower from off-idle all the way through Redline!"

so you don't have to worry about loosing low-end from stock although I don't know how it'd compare to the MWR w/ stacks as I haven't tested it nor know anybody else who has. It's interesting that the airbox shown in post #9 in the thread "Air Box Upgrade" shows much shorter and wider stacks installed into the carbon airbox. One thing's for certain, it should make more noise!

I designed the stacks that I've printed to have Ramair CC-106 filters fitted to them (These have a 90mm flange vs the 79mm on the K&N), they cost less than half that of a K&N RC-3250 (£24.99 vs £53.75) and they actually have 5% extra filter surface VS the K&N's despite being shorter. The total cost of all of the filters required (main filters, idle and breather) should be less than £70.

 

The rolled radius can be a more efficient design however it wouldn't really be compatible with pod filters as it'd be hard to fit the filters on and impossible to remove them. If I decide to make stacks for the stock airbox I'll likely add a rolled radius to the end.

The internal profile of mine is the same as the Beast-R stacks but looks more like a wasp PUK (Pictured below, minus the dimples) from the outside.

 

Managed to print a stack successfully, it came out real nice with no warping. I still have some minor stringing which I'll dial out for the next print and the support material was stuck on so well that I had to remove it with a hacksaw + screwdriver. Fortunately the stacks in perfect usable condition and snapped right into the groove in the intake pipe, I'll just have to give the inner surface a light sand with 600 grit. I've set my printer off to print another one with the slightly adjusted settings so it'll hopefully be even better. After that I'll just have to print another coil bracket.

 

Just realised I forgot to upload the pics of my installed stacks, unfortunately I haven't got around to getting the bike dyno'd and I'm not sure if I'll even bother in the end . I've got a Power commander installed at the moment along with the Q/S as I found it for only £70 and I can have it (the PCV) tuned in Aberdeen, only issue is the race ECU on the 796 doesn't disable the lambda sensors (from what I can tell) meaning that I'd need to get the ecu itself re-mapped in order to tune the lowend fuelling. This isn't really a viable option for me considering where I live combined with the cost, if it was an 1100 Evo sp then I'd probably do it but it seems like a wast of money on the 796 considering the suspension etc combined with the fact that it's my first big bike too! (I'll probably sell it Spring 2020)