New billet parabolic velocity stacks now available

[Sam-Q]

UPDATE: Now done and available, see post #28 for a pic



Thought people would find it interesting to see what I have been doing regarding some development work on velocity stacks.

Recently I for the first time had the option to get velocity stacks made by being machined out of a solid billet of aluminium instead of the current way of getting rolled and then fitted into flanges.

Due to material costs this was only feasable on the shorter sizes, the first batch is 50mm which is ideal for the RHD Corolla and Sprinter owners who wish to run slide on filters. They will also fit inside a blacktop airbox with a light shave on #4 and work better than anything else out there.


Right so being machined I have the liberty of choice in designing something new. From previous research I knew that the ideal design was a long taper to a parabolic opening and a full curved edge. This also known as a expodential, elliptical or variable radius curve. This gives the highest theoretical net airflow out of any of the designs.

Most of the velocity stacks on the market usually have some sort of taper but with a fixed radius rolled/machined edge, this has the highest velocity on the inside at the end of the rolled edge at the transition before slowing down again further down the tube. The parabolic design however lets the air keep speeding up all the way to the opening face.

More about the technical side of that here:

http://www.profblairandassociates.com/pdfs/Bellmouth.zip


Knowing all that I came up with this:

http://i127.photobucket.com/albums/p143/daunderdweller/sq%20engineering/in%20the%20build/50mm-ST-par-stack5_zpsa255e522.jpg (http://s127.photobucket.com/user/daunderdweller/media/sq%20engineering/in%20the%20build/50mm-ST-par-stack5_zpsa255e522.jpg.html)


Which I then had 3D printed along with a different design and a prototype exhaust mount alternator mount:

http://i127.photobucket.com/albums/p143/daunderdweller/sq%20engineering/in%20the%20build/3d-printed/stacks-and-alt-mount_zps3480e8f6.jpg

I sanded these smooth and had Jamie "Frak" being nice enough to put them on a flow bench for me. Here are the results in order worst to best, of note the OEM stacks where checked on a different day so the results might be a little off.

- Blacktop OEM: 320

- Silvertop OEM: 342

- HRC: 445

- IMEC: 483

- SQ model #1: 483

- SQ model #2: 489

All tested at 28 inches of water.

Two things really surprised me about this- first that silvertop flows better than black when to me they look terrible and second how bad both OEM designs flowed. This explains why people pick up power even when running short stacks in the OEM airbox.

Picking the better of the two and taking the chance at making a small adjustment to improve it further I gave the go ahead for a batch of both silver and blacktop sets to be made. This is when I was last at the machinist and only the outside profile had been cut:

http://i127.photobucket.com/albums/p143/daunderdweller/sq%20engineering/in%20the%20build/velocity-stacks1_zpsb6549eb6.jpg (http://s127.photobucket.com/user/daunderdweller/media/sq%20engineering/in%20the%20build/velocity-stacks1_zpsb6549eb6.jpg.html)

Next up is them getting the flanges cut.

Once done I shall have them back on the flow bench, this time all at once.

This is the part of my job that I love, I really look forward to how they turn out not just in flow numbers but how they look with a little bit of a polish.

[Matt]

When they are ready put me down for 2 sets of blacktop

[Sam-Q]

They where set back quite a lot because of what seems like a big shortage of 90mm bar stock or else they would already be done. They have told me between one and one and a half weeks. I shall let you know.

[Jimmee1990]

Good work Sam, always good to see someone doing some actual development rather than doing what everyone else does because it's good enough.

[Sam-Q]

thanks James,

I have pretty interesting to work the designs out and seeing it all come together. I really look forward to seeing how they are done. It's a pity I can't make my whole range like this but then again I still want to give business to the guy who rolls my existing velocity stack pipes.

[drift kid]

Good work Sam, always good to see someone doing some actual development rather than doing what everyone else does because it's good enough.

+1 great to see all of this happening man, great work!

[Sam-Q]

Thanks Ben


There is something I don't understand. There shouldn't be any price difference between the machining cost of a fixed radius bell-mouth compared to a proven to be superior variable radius design. So why is the company who has the most well known billet velocity stacks on the market (75mm) have the worse designed inlet and with only a gentle taper. I suspect they don't know and don't care. Makes sense though as they don't do much designing themself beyond reverse engineering to copy others, and when it looks good that's all that matters to most people.

I think this is the difference between me and other companies out there, I have a passion for trying to design the best possible within the budget available. Screw the whole exclusive thing, I want people to have the option of buying what I would want for myself on my car. Even if people later on ignore the fancy terms and the flow numbers and just think they look awesome and fit well then that's fine too.

Just incase someone is going to ask, no anodising unless there is a minimum amount of people all wanting one colour. Otherwise it's the same as when I had the first batch of RWD flex clutch lines made- had 4 or 5 options and the first person asking wanting one of the only 2 colours I didn't get- green. On request I can leave them unpolished though so people can get it done themselves.

[Frak]

Sam, they look magnificent, can't wait to see what else you have planned for 4age fans. :thumbup:

[Jimmee1990]

I can't wait for these to go with your 16v to 20v throttle adapters!

[Sam-Q]

So far it's not looking good for the manifolds. To get them made locally will be around 400 before I even make anything at all. I will look at other options now.

Velocity stacks should be done by the end of the week to mid next week.

[LittleRedSpirit]

Sam with some research you too can have things made in China! You could probably find out who machines the ttt ones and have them make your design for you. Business ethics isnt a concept over there.

Also, this is great engineering at play. I have another idea to do with tpi style itbs and parabolas that might peak your interest too.

[McLEVIN]

Id rather pay more for locally designed and made

[Frak]

Id rather pay more for locally designed and made



:thumbup:

[LittleRedSpirit]

Everyone agrees with that in principle, but far fewer people put their money where their mouth is when they purchase things these days. Speaking as someone who builds things in Australia from Australian materials for the most part. It depends what 'more' is, and if we are talking about 1.5 to 2 x the price then, from my experience, you can not often compete. Every company with stacks for sale has some spiel about how they are better and a bunch of jargon about optimised flow and airspeed and tapers and whatnot, with no real numbers. Having supporting numbers would be a great thing. The flow bench data is excellent, but I would like to see credibly conducted hp tests as well. Perhaps putting you over the top of the other types out there, no matter what the price.

If you want to cater to people who will pay a premium for their parts then for the most part you are not talking about most youthful rwd 4age owners. You might not be rewarded like you deserve to be for making superior products. Its a philosophical question for most any manufacturing business at this time in the first world.

[Slimer86]

Good to see after all the misinformation on the internet (false accusations that they are too short, won't work etc), frak has come through with the goods once again.

I read his initial dyno findings on using imec stacks in the standard airbox (many years ago). It was the only quantitative information I found. So much objective misinformation on the net about flow and performance of products.
Frak, from all the ae86 / 4ag community, thanks!

[McLEVIN]

Frak I hope you are secretly working on a book. Uncle fraks 4age bible.

[Frak]

Chris I have thought about it, If I had the spare time I'd love to put a 16v our engine dyno, stock and then do like a mild tune on it, thinner head gasket, cams etc. I already have a large collection of jdm headers 4-1, 4-2-1 etc. I'd also like to do the same with a 20V, I have spare ST and BT lying around, then document everything, just need the time.

[dove grey 64]

Luckily the 4age market isn't just supported by youthful owners, how many young kids have clubman kit cars?

[sundee]

So far it's not looking good for the manifolds. To get them made locally will be around 400 before I even make anything at all. Hard to compete with the chinese made T3 parts. I will look at other options now.

Velocity stacks should be done by the end of the week to mid next week.


Sam, your doing a great job here, really you are.

you seem to have a pretty big brain between those ears, which is a good thing.

but i just wish you could design products without slagging out others to make yours seem better.

I dont know where you get your info from, but T3 parts are NOT made in china, they are all made in-house in the US.

by making outrageously incorrect statements, your just taking away from your talent, and your making yourself look like your a 14 yr old idiot.

keep up the good work, But focus on your work, not making stories about your competition.

[Sam-Q]

LittleRedSpirit: yes you're right, I didn't want to take them there and there is no assurance of me getting anything at all let alone a good quality product. Unless I find a company known to do good work?

McLEVIN: I wish more would think the same. Matt is right though, when most people just look at the price and don't know the difference in the design or quality companies like mine loose out. What I need to do is make something cheap enough that not only still looks really good but works well. It's a good thing I am prepared to have low profit margins. I for a long time just went along with my own mind set of making crude look parts that worked well thinking if they would be cheap enough people would all want them. I needed to look further than my own preferences and when I had things outsourced my margins where lower but I was able to sell more and it frees up my time to do more RND like what's here.

dove grey 64: I can say that after performance workshops Clubman owners are usually my favorite customers . They usually know exactly what they want, are prepared to pay for it without haggling and don't send me long e-mails asking me questions. A pity there are not many of them. Also they usually are pretty happy to correct me on the forum which is good, I want to know if I say something incorrect.

sundee: thanks Joel, once again you're right. I found out my info was wrong about where the parts are being machined, I found out they have an in house 5-axis. I hate false info so I edited my post to remove that. Wasn't trying to make myself look better at all and it wasn't something I made up randomly though. It was through my machinist oddly enough that I found out the truth just the other day. What sets me off is rather frustration in differences of mindset and the copied products. This isn't something I worked out of bogus info, it's probably best not to go into the specifics or discuss it here. It is unprofessional and I need to remember that.

[LittleRedSpirit]

Wonder whats going to happen if ttt starts making a parabolic design. I hope the expectation of ethics goes both ways. Patent that sam!

Its always best to focus on your own strengths, rather than perceived weaknesses of others. So often its just your own perception thats wrong, and that makes all your claims baseless. Instead of taking the chance to put out your research and findings which are the real selling points anyhow.

[LittleRedSpirit]

Luckily the 4age market isn't just supported by youthful owners, how many young kids have clubman kit cars?

I think far fewer than kids that have ae86s'. They tend to go to places ike Yager for their performance stuff and pay someone to do it all. Sams best way into this market is to approach Yager and the like and sell them on the benefits of the product. However without any kind of patent you cannot really claim the design. They may well just buy a batch, copy the idea and make their own, especially if the price is high due to 100% australian manufacturing. I beleive if you can deliver the product around the same price as the competitors, that you will outsell them. If you do really well expect a lot of similar things to pop up though.

Any good product gets copied eventually by someone who can make it cheaper. The european soft close drawers which cost $80 for a small one have now been copied in my industry, and they can be had for $28 for the chinese copies. Yes they arent as high quality, but its not the kind of difference a layperson could appreciate. You would be prolonging the profitable part for longer if you do manage to outsource things, and you would make it harder and less profitable for the competition to undercut you, and you could roll the price down once systems were in place for production and you have covered your r and d and setup costs to stay competitive. The way inflation has been going, commodity prices, and the cost of labour in australia, its hard to see it being viable to make them here in future.

[Sam-Q]

Can't patent something that's already existing and also it takes hundreds of thousands to challenge one. You and Joel are both right about your points. I need to stop with the mud slinging and instead make a general point of how what I have is better that other products in general instead of any one specific company. I need to put aside any personal grievances and just focus on selling my strong points of trying to offer the best I can. I think Jamie here helping with hard flow numbers is the right way to go. The flow bench doesn't give a crap how much or little you think of something. If I can get hard numbers to prove things then why not. So you guys keep doing what you're doing, I do appreciate the input.

I until recently didn't know the Yager guy was still around. I tried for a whole year to contact him to offer him money for his thermostat outlet design before making my upgraded version of the same concept. Even then I wouldn't of done so if he still sold them. Same goes with the HKS oil pressure kit, I for the first time directly copied something, but only because it was no longer sold. You're mostly right about the clubman guys though. They do buy the occasional bits off me like genuine parts, if it comes to engine building they wouldn't even ask me, which suits me as I don't that much about the specifics of some things in a build.

[Frak]

Sam willing to help anytime, you just can't beat hard facts! Sam we are moving workshops, the engine dyno is getting moved into the new premises, I am going to get my butt into action and get that BT mounted up to the engine dyno, will have to fab a few bits an pieces but I think it's about time to do some BT 20V engine testing. I want to try a heap of headers including standard, different ram lengths, and a set of Poncams would be a nice test.

[sundee]

Thanks sam, i would really like to see your new design put to test on a motor, and compare it to a standard 20v intake and to a constant radius stack

[Sam-Q]

I agree Matt, theory is one thing but often reality doesn't agree. I am fairly confident that this design will help in the real world, I just don't know by how much. It would suck if it all just made the same power or to my horror less power. It would need to be against something the same length though so it would need to be something like the 50mm Jubride.

Jamie and I have already talked about trying different things on the engine on the dyno, I look forward to it. The one I want to see the most is stock airbox and trumpets compared to aftermarket open.

[Sam-Q]

Thanks sam, i would really like to see your new design put to test on a motor, and compare it to a standard 20v intake and to a constant radius stack

For sure, we need to find some that are a 50mm length though or else we can't directly compare. The Jubride is the same but we don't have them handy to try, they look like this:

http://www.jubiride.com/upload/PO16-20071228205219-1.jpg

Although very hard to make out, it doesn't look like they have a good transition between the taper and straight section. Rather a sharp edge, but maybe that's just how it looks in the photo. Even then what if they work the same as mine, would it be because of the big taper making up for the bell-mouth? The only way I can see a true test is for me to get a single set machined that do have a fixed edge which isn't going to happen.

[Sam-Q]

Update time:

http://i127.photobucket.com/albums/p143/daunderdweller/sq%20engineering/Custom%20parts/4AGE-20V/20V-parabolic-velocity-stacks-1_zpsf276ab73.jpg (http://s127.photobucket.com/user/daunderdweller/media/sq%20engineering/Custom%20parts/4AGE-20V/20V-parabolic-velocity-stacks-1_zpsf276ab73.jpg.html)

Blacktop on the left and silver on the right.

I used a 260 degree cut hole instead of a slot for the blacktop so it still locates true every time while still keeping a common price and material size between the two different models.

I have lots of these in stock so if anyone wants some then let me know.

Time to go back to the flow bench now.

[drift kid]

Ooooh, perdyyy

[McLEVIN]

I have a nobby booth carbon airbox It would be better for me to run these trumpets inside rather than just the airbox?

[LittleRedSpirit]

if they fit, then yes it would be a lot better.

[LittleRedSpirit]

What are the prices for those playing at home?

[Sam-Q]

I have a nobby booth carbon airbox It would be better for me to run these trumpets inside rather than just the airbox?

If you have nothing inside at all then it should make a big difference. Do you have a blacktop? I also have 30mm as shown with this Mekaru airbox:

http://i127.photobucket.com/albums/p143/daunderdweller/sq%20engineering/reference/30mmstacks-mekaru-dean-doncaster_zpsaa017b46.jpg

[McLEVIN]

I have silvertop on a 16v

[Sam-Q]

Right now I don't have anything to suit a silvertop that's short. So unless you can fit a 50mm in there as per your original request then it would be a real long wait to get something custom made.

How is the internal room, have a photo handy?

[Admiral Ackbar]

I have a nobby booth carbon airbox It would be better for me to run these trumpets inside rather than just the airbox?

Not necessarily, you need to check clearance between the ram tubes and the walls of the airbox (both opposite and sides). Try for 1.5 diameters clearance, any less than 1 diameter will really hurt performance.


Sam: Inlet length is far more important than fiddling with the radius of the entry. If you look at superbike and f1 engines, they nearly all have a straight tube with a single radius on the end. Admittedly this about all they can fit, but it shows that a basic design works very well.

From memory a bigport inlet port is about 80mm + TTT quad adapter 60mm + blacktop throttles 75mm + 50mm ram tubes = about 265mm, which is a lot shorter than ideal for an engine revving to 9000rpm.

[Sam-Q]

Joel I completely agree with you that length plays a more critical role. As mentioned previously these where designed to be the best optimisation of a bad compromise where we just can't fit longer. The inlet design does make a real difference so it shouldn't be discounted. Quite a few times now I have been envious of all the intake room available in the left hand drive cars.

[Admiral Ackbar]

What you could do is sell 2 pairs of different lengths, so have cylinders 1 & 4 short and cylinders 2 and 3 long. One of my bikes had this arrangement to broaded the torque curve, and it certainly seemed to work. Definately need to have individual cylinder trim though.

http://www.gstwins.com/zx6r/images/stack%20off.JPG

[Sam-Q]

Yes the trim is the problem, for the people that do have an ecu to support significantly fewer again would be prepared to go to the trouble and cost. No argument about the theory though, spreads the tuned point.

Although hard to make out those look like they have a variable radius inlet.

[Frak]

What you could do is sell 2 pairs of different lengths, so have cylinders 1 & 4 short and cylinders 2 and 3 long. One of my bikes had this arrangement to broaded the torque curve, and it certainly seemed to work. Definately need to have individual cylinder trim though.

http://www.gstwins.com/zx6r/images/stack%20off.JPG

Hi Joel, I tried this on a BEAMS, can't exactly remember what the outcome was, will have to look back at dyno curves. But it didn't work. I own a Honda RC45 which is fitted with a HRC kitted engine, they run 20mm and 40mm ram tubes on the throttle bodies and as you said this is common on motorcycles. Infact a number of years ago, I tuned a WEST race car fitted with a zx10R engine, one of the experiments we did was to run it with the standard 2 long/2 short ram tubes, then fit 4 short, then 4 long.