Beams velocity stack length tuning

[Tim.duncan]

Hey guys

We have been playing around with different length velocity stacks on the quads

http://ghettogarage.org/2011/11/18/the-sound-track-to-my-dreams/

I found it interesting to see how such a small thing like the length can change how the motor performs

Iv got more info coming in a couple of days

[Rice86]

Round of applause. That's good stuff your doing there

[AJPS]

yeah

I had 110mm on mine and now ive gone down to 100mm stacks and there was a difference....

good thread

[ke_70]

so was the red line the 30mm stacks vs. 70mm?

you make amazing torque

[Tim.duncan]

Red line is the first power run when I got the car
109kw
The blue is vvt tuned and 70 mm stacks 126kw

I have a graph with all the runs between the different sizes... But you have to wait ha ha

How do the 100 fit under the bonnet Dave? Where did you get them?

[ke_70]

ke70 have more room than ae86's

you should have a tad more room on yours tim cause you motors mounted straight.

[AJPS]

from sydney, they have 110mm and you need to add your own flange

[Frak]

There is still more in this engine!

[70XIN]

I'd love to see the dyno graph between different sizes, cause at the moment - it's just showing the power of getting a retune :P

[ke_70]

is this the first beams you've played with jamie?

[Frak]

Yes it is and I must say I'm loving it, I really like it. Once Tim puts up the torque curves of the different lengths, look at where the dip is, at first I said to Tim that I believed the dip was caused by the quads, then after seeing the standard curve which is nice and flat I was sure. Then after trying different tube lengths change where the dip is, obviously an intake resonance problem.

I reckon there is still more in this engine and to be totally honest we actually haven't spent that much time on it, huge gains changing cam position(vvt), you must hear this thing on the dyno in real life, at about 6500rpm it gets this incredible intake shrill to it, I'm sure Tim can elaborate more but as we have been tuning it, it's been getting angrier and angrier.

If you look at his first power run before we had a look at it, basically where it climbed out of the dip it really only had a 2000rpm wide band, my initial aims were 125kw and to extend the power above the dip another 1000rpm, well we have exceeded the kw figure and not only did we extend the rpm about 1000rpm higher but also about a 1000rpm lower.

I really like this engine, foe an NA 2 ltr it really delivers, I have dynoed a number of F20C S2000's and they too deliver awesome kw for an NA BUT at 9000rpm, where as this engine just cranks the torque. Tim is coming in early this week to give us plenty of time to clean up the map, so I'm hoping for more mid range torque.

Just for the interest of readers when we initially were messing with the vvt, I was picking a certain load point and just getting a feel for how much extra/less torque we'd get as we changed cam timing, some of the gains were MASSIVE, there was smiles all round.

Great engine.

[ke_70]

very good!

feel free to play with mine anytime you want :) haha

[Tim.duncan]

got any links dave?

the graph will be up on the blog on sunday

the induction sound has changed so much! used to be nice, smooth and deep. now its just angry and LOUD! soo soo good!!!

[Tim.duncan]

http://ghettogarage.org/2011/11/20/3sge-beams-velocity-stack-testing/

[ke_70]

interesting... i thought for sure you'd get better gains with the 100mm

[Celica RA45]

you need to look at the torque and also were you moving inlet back at all .rule of thumb 380mm from back of valve is what you are after .also it also depends on what extractors you are using as well
on vvti as the power starts to drop off ,retard 500 rpm before by a couple of degress as inlet moves 5 to 255 lifter rise . and i use exhaust to move the reversion around

[Tim.duncan]

Clay I have a feeling the motor wants 100, but the bend and the poor bell on the stock stacks have stopped it flowing enough air over 6k

[Tim.duncan]

Glen we dident have the time to play with vvti with each set of stacks.
The motor is getting a good tune on wed so I will try retarding the inlet after 5500 then

[Celica RA45]

those ae111 ram tubes are the pits.try some different sizes and change in size every 20mm

[Tim.duncan]

They are the only sizes we had lying around
I would love to go more in depth but we are getting allot done considering it's a tafe course ha ha

[ke_70]

what about if you make up temporary spacers?

you have easy acsess to a mill don't you?

[Frak]

I'll measure one up today but I think the AE111 are longer than 100mm I thought about 140mm.

[Celica RA45]

well any up dates

[Tim.duncan]

Have ordered some 110mm stacks, should be around 2 weeks. Hopfully see some more gains

[Celica RA45]

you see this is where my curved ram tubes help .any way good luck see you guys in 3 weeks

[ke_70]

so it didn't get on the dyno on wednesday?

oh and silly question but, how does one determin the total length of a curved stack?

[Celica RA45]

you put a line through the center of the ram tube and take measurement from that

[Tim.duncan]

only quickely on wed, had a few dramas... i dont want to talk about it

how do your curved ram tubes help glen? able to fit more length under the bonnet?? i hope the 110mm fit.. ha ha

[Celica RA45]

yes thats the idea by curving these down over 25% it doresnt effect air flow ,any way see you guys in 3 weeks off over seas

[ke_70]

will you be bringing presents from NZ glenn? haha

[Tim.duncan]

Latest developments

http://ghettogarage.org/2011/12/02/stacks-on/

[Frak]

Nice :)

[Sam-Q]

there you go Frak, something to have fun with next time on the dyno.

I really want to see how these fare against the others.

[Frak]

Sam, we'll run it up this Wednesday, will be interesting to see.

[Grant #2]

Here's a question:

Does anyone know why the intake tract is so long on FA engines? Being such a peaky engine, I would think that the intake tract should be short to cater for the high RPM, yet I see this:

23262

I have theories but I don't know for sure.

Also, as far as the Blacktop OEM trumpets choking things off on the Beams....would this maybe not be as much of an issue on a stock blacktop engine that isn't flowing nearly as much? As in, it might benefit from the mid-range gains but maybe not reach a choking point until a really high rpm?

[plohl]

I would have though it would be to make the most of the engine over the whole rev range. If the engine is set up to produce most torque at a high RPM, the gains for tuning the exhaust and intake system would be very small, whereas increasing mid range torque would offer far better gains and produce a more 'drivable' car.

[Sam-Q]

That isn't the case. In real world test on a 4AGE engine it seems you can get the harmonic theories and throw them in the bin. I don't have the most experience however I have yet to see any case where someone has lost power anywhere in the rev range by running longer intakes. I supplied a customer with the same 110mm trumpets as what I have here, he also by coincidence previously ran the same B/T T3 trumpets previously. In his case he picked up good mid to top end power, also apparently they made a shitload of noise. He had a 20V though and so this is one of the reasons why I am so intereted in the results of this dyno run.

[plohl]

.....has lost any low end power by running longer intakes.....

Do you mean top end power???

[Sam-Q]

yes indeed your right, I will edit

[Sam-Q]

I have also moved this to the technical section, seems more appropriate

[assassin10000]

Just a thought: the long length on the TRD setup may be because of tuning the resonance for the '2nd' wave at a high (10k+) rpm, instead of the usually 'settled' for 3rd wave.

Andrew

[Grant #2]

Is there an advantage to tuning for the 2nd wave?

Sam, do the 110mm stacks for sure not fit under a factory blacktop air box cover?

[Sam-Q]

even the 70mm stacks are a tight fit in the factory airbox, I wouldn't even use them though because I would have serious doubts about how even the air would be to each cylinder

[AJPS]

my car made 141rwkw with 110mm

will do a retune now its got 100s

[assassin10000]

Grant, here's a good read on it.

http://hemrickperformance.com/induction.aspx

Basically it get's weaker with each 'wave'. Law of diminishing returns.


Andrew

[Tim.duncan]

http://ghettogarage.org/2011/12/10/3sge-beams-dyno-final-harrah/

[Tim.duncan]

Couple of vids

http://ghettogarage.org/2011/12/11/the-clock-we-wind-it/

http://ghettogarage.org/2011/12/12/scent-ledorp/

[AJPS]

what are you revving it to at 137kw?

[Tim.duncan]

7500
We had the dyno wired in to read it

[AJPS]

i took mine to 8k

made a touch more, but not much

[assassin10000]

Just out of curiosity do you have a copy/comparison of the staggered length dyno run? I understand what it 'should' do in theory, but I'd be interested to see what it actually did on your motor.


Andrew

[Tim.duncan]

We just revved it till it stopped making power which was 7500 the limiter is set at 8 but I'm going to lower it

I'm really impressed considering it's all stock including the exhaust headers

I'll have the graph of the 4 different length set ups soon, I'll post it as soon as I get it

[assassin10000]

Cool.

I personally would leave the limiter at 8k (stock is 7800 on a manual motor anyways). The extra 500 rpm could come in handy, instead of having to upshift then downshift before a corner it might let you get a hair more acceleration/carry your speed better.


Andrew

[Frak]

Tim, I'll do the printouts this afternoon including the staggered lengths.

Assassin1000, the staggered lengths did sort of what I was expecting, I was hoping they would widen the torque band with little peak drop, didn't work out exactly like that, they did sound good and look unusual though!

[AJPS]

yeah this is what i did

and my motor has stock pipes on it as well
Cool.

I personally would leave the limiter at 8k (stock is 7800 on a manual motor anyways). The extra 500 rpm could come in handy, instead of having to upshift then downshift before a corner it might let you get a hair more acceleration/carry your speed better.


Andrew

[Tim.duncan]

I dident realize the stock limit was 7800 I thought it was 7

Good to know!

[assassin10000]

Yeah it's 7200 on the auto version and 7800 on the manual version, IIRC.

Andrew

[Tim.duncan]

How much timing you running Dave?

[Celica RA45]

you should be able to go as far as 28 ign timming with 26 at the top end
and tim how long is your inlet track now from back of valve
are you anywhere near 380mm

[AJPS]

I think im running 26

and tims will be same length as mine i guess?

[Tim.duncan]

you should be able to go as far as 28 ign timming with 26 at the top end
and tim how long is your inlet track now from back of valve
are you anywhere near 380mm

I'll measure it when I get home
Do you know the distance from the valve to the head?

[Celica RA45]

i thought about 110 to 120mm cant remember

[Rice86]

that's amazing

would the theory on this be the same with a 16v 4age with quads or a 20v 4age?

[Sam-Q]

that's amazing

would the theory on this be the same with a 16v 4age with quads or a 20v 4age?

theory I don't know but in practice yes. I had a customer do the exact same change- T3 70mm blacktop to my 110mm set and he picked up mid + top + lots of noise.

[Slimer86]

Cough...
http://www.profblairandassociates.com/pdfs/RET_Bellmouth_Sept.pdf

[Tim.duncan]

last bit of info

different length (please note the 35mm made 120rwkw with same conditions as the others)

http://www.ae86drivingclub.com.au/dcimages/2/9/270566.jpg

torque between 75 and 110

http://www.ae86drivingclub.com.au/dcimages/2/9/270567.jpg

bonnet open vs shut

http://www.ae86drivingclub.com.au/dcimages/2/9/270568.jpg

[Celica RA45]

try 90mm and see what that does

[4.5AG]

Hi Tim,
Have you measured the distance?
Cheers....

[Tim.duncan]

no sorry have not had much time to play cars... ill get some measurements over the week end

[Tim.duncan]

http://www.ae86drivingclub.com.au/dcimages/2/9/555296.jpg

back to the side of the head is 242mm, add glens 110-120 to the top of the valve puts it at around 352-362

did you find 380 the best length glen?

[assassin10000]

Did you measure both the 'long' and 'short' sides and average them, due to the angle of the manifold adapter?

Andrew

[Tim.duncan]

no.... but that makes perfect sense wops ha ha

that measurement is just from the top

[assassin10000]

I figured as much, lol.

If you still have the manifold off, take a piece of wire and form it along the top of the intake port to the valve, and another along the bottom of the port to the valve and average those for port length. Mark or cut them, then straighten and measure.

Andrew

[Tim.duncan]

good idea

but im not really doing any more further development on this so not really bothered

would love to stick one of these motors on an engine dyno and get really fidley with it changing inlet and exhaust around to see the different effects

[Celica RA45]

all i do is open the throttles and put a tradys plastic ruler down the port with the cyl that has the inlet valve closed and measurefrom back of valve till it hits the bellmouth ,this should be close
im at 385 mm at the moment and power drops off at 9k with this length

[Celica RA45]

new special ram tubes are now ready will take a pic this afternoon and put up

[Tim.duncan]

INTERESTED!!!!

when will you get a chance to dyno it??

[Celica RA45]

1 broke when i was setting these up ,so it wont be for a while ,but i am dyno tuning a new motor new week end with the same length so see if i can get a idea
also have changed diff ratio and gone up to bigger tyres 225 on the back now and also 4,55 ratio. so it was 205 and also 4.3 originally

[Rice86]

bumping this up

so say i have a 16v bigport and if i had an ITB adopter plate that was longer in length then the T3 adopter, but this longer adopter had a bend design to them, will this effect air flow/overall performance?

i got my eyes on a set of different adopter that's for sale and never seen this kind of design before..will this act the same as having longer stacks?
will it act like having stock 20v stacks as they also have a bend from factory?

or am i just better off with a more straight setup like most typical ITB setup?

here are pictures of the adopter in question
http://www.ae86drivingclub.com.au/dcimages/1/0/3/1/396460.jpg (http://imageshack.us/photo/my-images/824/img0917e.jpg/)
http://www.ae86drivingclub.com.au/dcimages/1/0/3/1/396461.jpg (http://imageshack.us/photo/my-images/842/img0916nf.jpg/)

[ke_70]

also interested in this.
this is the 16v head cross sectioned.
26401

as you can see the port come in at 90 degrees then turn down rather harshley.
how would angleing up the inlet manifold affect flow into the chamber? i know there wouldn't be much in it.

[timbo]

That manifold would be great for the fact that you would clear the brake booster.

[LittleRedSpirit]

Curves in inlet ports I believe can help acceleration of the charge (torque) and also help mix the fuel into the air better I thought. I may be wrong but its what I've been told. Playing with where the butterfly and injectors are is also able to change the result. As I understand it, the closer the injectors and butterfly are to the head, the better (more efficiently) the engine will perform at low rps. Conversely, if you move the butterfly and squirter's farther away then you can have a better fuel mix at high rps and a smoother less turbulent air stream. I've tried to design my 2az manifold to give balanced performance but specifically to peak its efficiency at 6500rpm. The injectors in the head that shoot right at the valve will be good for efficiency, but I may look at introducing a different fuel or fuel source further up the inlet some day. The engine isn't designed for high rpm like a beams so this may prove unnecessary. I just have to see how it goes.

On the 2az, which I know is quite different to a Beams I ended up going with the butterfly 192mm from the valve top (as its about as close as you can practically make it), and a total average inlet length of 345mm from the back of the valve. I have about 5 degrees of tilt to bring the throttles down, but you can still clearly see the valves through the trumpet with the butterflies open.

Also, the length of inlet and butterfly position are related to inlet cam timing, and there are certain guidelines about the inlet length vs rpm and cam timing that you can follow. See the table below.

My engine with vvti all the way on advancing the inlet cam, it will close at 20 after BDC, which even though there is no line on the table, we can extrapolate as being suitable for around 2000rpm. Then with vvti off allowing the cam profile to shine through and close 60 after bdc, we can see that my length is suitable for around 5000rpm. By reducing the trumpet length I can Push this to a matched length for 6000 or even 7000rpm. I've been after a torque monster type set up with this, hence why my inlet is designed to be most efficient with standard cams and to highlight the peak torque range of the standard power delivery, which is listed as:

Thanks to Wiki: "Output is 117 to 120 kW at 5600 rpm with 162 lb·ft (220 N·m) of torque at 4000 rpm"

Since the 2azfe is a fairly long stroking motor to begin with, I don't intend on rotating it faster. I'm just increasing compression to 11:1 from 9.5 or so, adding itbs and keeping a fairly long inlet that is a little more focussed on the torque than hp output, but with room to tune and adjust.

My throttles have been spaced apart an extra 10mm over standard because that is the difference in port spacing between a 20v and a 2azfe. This allows me quite a big trumpet bell mouth and still 3-4mm in between each one. I wonder what effect this has. I can try my T3 trumpets as a comparison later I guess. The trumpets are just under 100mm long, maybe 94 or 95mm.

I found this table useful:
http://www.ae86drivingclub.com.au/dcimages/6/2/8/396511.jpg

[LittleRedSpirit]

Something else which I've always had a theory on that Id love to see you guys test on the dyno, is a measure to enhance the reflection of pressure waves back down the inlet.

Remembering back to science class aa a boy, I recall that a parabola will gather or focus light to a point (like car headlights), giving it a directional focus. Could a parabola do this for any waved energy, eg air pressure waves. If so, Is there some benefit in having a parabolic cap above each trumpet built into your trumpet enclosure to enhance the reversion of these waves. I know some makers of ITB trumpet style airboxes, eg Jenvey, mention the advantages of having a flat face opposite the trumpet opening to reflect pressure waves, so I wonder if a parabola would do this more efficiently?

Thoughts?