Derracudas zermatt 20vt,6spd, 351awhp - July 4th drive vid

[derracuda]

Seeing as how you like melting stuff you might want to try your own casting.

DIY casting style (start saving your beer cans)

http://video.google.com/videoplay?docid ... l=en&emb=1

you're full of good ideas, come on by, we can cast and weld all sorts of stuff!

[Hank]

Derek, welding thin delicate pieces like those slits to a thick piece like that plenum material can be tricky. A few tricks can help you out a bit. First, make sure you preheat the bigger, thicker metal. Welding those pieces will be easiest on the two ends.. Doing a fillet weld will require too much heat. You can tack the two ends down, and then work off that weld. Mark where your weld is going to be(ie, the front and back of the blade) and then without the piece there, go in and weld a bead that is somewhat vertical on both ends so that the piece sits on those two welds thatl ook like buttons. With the part preheated, point it at where you want the weld to happen, and then really hammer on the pedal in an instant. THey call this zap tacking, and the idea is to get a ton of current into the part as fast as possible so that the heat does not have the chance to get out to the rest of the part and melt it down. Make sure you have gas flowing prior to it, or you wont get a good tack..

Also, make sure your ground is directly clamped to the big part.

[derracuda]

i don't really have a way to preheat the part unfortunately. i'm trying to do what i can and then i'll have someone weld the bigger stuff for me. i may have to have someone do more for me that i'd like. my inexperience is killing me here, but i'm trying!

[jitsu303]

i don't really have a way to preheat the part unfortunately. i'm trying to do what i can and then i'll have someone weld the bigger stuff for me. i may have to have someone do more for me that i'd like. my inexperience is killing me here, but i'm trying!

Even preheat with a propane torch might do?

[Dr.Strangelove]

[/quote]

What IM is this piece from?

[derracuda]

http://forums.hybridz.org/showthread.ph ... 863&page=8

[Dr.Strangelove]

[Hank]

yeah, a propane torch works well. A cutting torch works well. Take ot the oxygen so you just get that black soot all over the part, then heat it with the torch with the oxygen on till it is hot enough to burn off the black, and then you know it is at the perfect temp for welding. It works pretty well...

You can also just use the tig torch. Hold it high enough in a non critical area, and it will not scath the surface at all.


Looks good. I think it will work Captain. (do you have to have the actual degree to call others captain?) :-)

[teamplatto]

try to put your parts on your oven, where you cook your eags, directly on the heater, it gets hot pretty fast. this is what i do when i weld big chunk of aluminum.

[a_CQ]

Braze the little pieces??

[my2000apb]

ok, breakthrough! last night i got the tach to work!!! WHOO HOOO. i played around with it for a while before but i missed one ground wire for the tach. there's just so many wires so i now have an operation fuel gauge and tach... that's half the display. now for the temp gauge and speedo. maybe i'll get a video of me starting it and revving it a bit bbiab..... *runs out to do so*

so for the tach, the red blk yellow goes to terminal 1 on the coil, the one with the blue wires, i had the red/blk/yellow just hanging right near where the battery tray was with a similar sized black wire lead right near it. so where does the black one go? is that powered? does it go to the 15 terminal?


also im wiring in an innovate lc1 and gauge, can i get sensor heater power from here, (pic below)

Attachment ( 17709 ) : o2 sensor heater.jpg

[Longitudinal]

You can also just use the tig torch.

I just learned this one at the welding lab. It's a good trick to know!

[Wizard-of-OD]

death 4kqt wrote:[/quote]

realize there is a lot to be learned from people on the feild who are actually doing the work. 8)[/quote]
Because all Engineer's are paper pushers.. :wink:

considering I am the one of the only people in the VW/Audi community aside from Donato Rossi that did extensive research on intake manifold design AND DOCUMENTED TESTING specifically towards the intake plenum I would hope I have some experience in this matter.
I am sorry I did not give a winged out explanation as I did not have the time that day but I will try my best to do that now.

Spoken just like the engineers I work with or the local building engineers that weren't going to OK a planned system I was using because they had never seen it used and didn't like it.

And I am sure they had a valid reason as to why. :-)

Sorry D,
did not get a chance to elaborate the other day.Was hoping you would PM/message me for an explanation on this but I guess here it goes.

well.. huh. i don't think this alum. is sturdy enough for some heat i was really easy on it too!

Good...scratch that idea.

Ok from the top.
The reason why "I believe" that those will not work as they will create turbulence in the plenum.Not to mention if you do manage to weld the aluminum half moon pieces in there, you will have to sand down /polish the welds to reduce turbulence over the straighteners.

In my findings the following hurt rather than help airflow out of the plenum and into the runners:
* ITB's
* Air straighteners
* The dual slot plenums (lemands,dahlback,etc)

Lets reference the SEM Motorsport intake manifold which has been proven to make more power/torque than any manifold on the market currently.

http://www.inaengineering.com/gallery/m ... alNumber=1

The key here (and this is the major factor) is aligning the throttle body so that when it cracks open it hits the wall of the plenum opposite the runners causing the air to "taper" down the side of the plenum.

Keep it simple - you allready have the plenum material and the CNC'ed back plate for the runners so just design a throttle body neck that will do as described and you will be golden.

I can show you a whole bunch of cool CNC'ed parts that are pretty much useless and most of them are in the aerospace industry.
Are plenum slots an idea? yes
Are plenum slots a great idea? I do not think so

[derracuda]

so wait a second Issam, you're saying that Audisport has no clue that their dual plenum intakes, used since the 80's, are junk?

no doubt there is a lot more science to the creation of a super effective intake manifold than i'm able to scientifically test to the enth degree, but i don't think that Audisport would have been using them this long if they weren't effective. that said, i'm not blindly following the idea of "well they used it so it HAS to be the best idea ever", i just am willing to bet a cup of coffee that there is a pretty good reason that design is employed, and for so long.

i'll keep tooling along. so long as my manifold doesn't hurt anything or seem to have any adverse effects once the car is back on it feet, it'll stay in place. one for my history books in experimentation for the fun of it.

[cuatrokoop]

One thing I know about air straighteners, is that they were designed for external fluid flow, and I'm pretty fuzzy on details since it has been about 5.5-6 years since I've dealt with aerodynamics (I've run sonic and super-sonic wind tunnels). But I believe the goal behind them was to help with boundary layer separation on the upper surface of a wing. If the plenum was a suitable volume, with a Re to take advantage of the characteristics of the straighteners, I'd say do it. But honestly D I don't think you will see any gains by doing them. So, if you want to do them for the cool factor fine, but I really don't think there is a need. Will it hurt the performance? Probably negligible. Are they going to be a PITA to weld in? Yes, I could have told you that and I've only ever TIG welded steel, but I've been around a lot of aluminum welding and have seen it gone bad for doing "dumb" things like improper torch settings (feed rate wrong, heat wrong, wire selection wrong, piece sizing, you name it).

But anyway, I'd highly suggest grabbing a book or two on the subject before you get too far, or be prepared to spend a lot of time with a flow bench, cut off wheel, aluminum bits and a torch to try and balance the air flow, pressure drops, etc across your runners. I think that is more what Issam was trying to say, more or less.

Not sure I can see how Dahlback or Lehman screwed up their plenum design, since both had huge exposure to the Audi Sport pieces which likely had a great deal of engineering time spent on them. Also not sure how a well done ITB setup hurts performance of an inlet system. If ITB's were bad, BMW wouldn't have used them on a production motor or two, bike manufacturers wouldn't still be running them, etc. I do agree that how the plenum transitions to the "velocity stack" portion of the throttle is key but again if the plenum and runners are done right, the velocity at the choke point will be spot on target if you tune to a small RPM range. Otherwise, as with ANY intake system you have to make compromises in sizing.

[Wizard-of-OD]

so wait a second Issam, you're saying that Audisport has no clue that their dual plenum intakes, used since the 80's, are junk?

Audisport did not design motors for

no doubt there is a lot more science to the creation of a super effective intake manifold than i'm able to scientifically test to the enth degree, but i don't think that Audisport would have been using them this long if they weren't effective. that said, i'm not blindly following the idea of "well they used it so it HAS to be the best idea ever", i just am willing to bet a cup of coffee that there is a pretty good reason that design is employed, and for so long.

You are not building an engine to be in the same league as Audisport Derek so you can not expect to apply what they have done into your application.They had restrictions...you do not.
Furthermore the project from HybridZ is also running ITB's which brings another factor into the plenum design.

Do not follow the "well Audisport did it so I am doing it"

a few years ago, a bunch of us bought and donated every 1.8T manifold on the market for testing purposes (this was before the SEM manifold saw light) and these were the results:


By definition the Dhalback plenum is much larger than the stock OEM unit but you can see how the slot hurts airflow (both individual and overall).
Whatever the case,this is a really controversial topic,I have given you my advice on what you can do with regards to the plenum design.It is up to you to do what you want with that information.

Good luck.

[Dr.Strangelove]

You will need access to an engine dyno to determine the optiman runner length/shape and optimal plenum shape. Intakes and exhaust systems are voodoo black magic throw the chicken bones pieces of an engine and need to be designed as such. You could do Helmholtz http://www.phys.unsw.edu.au/~jw/Helmholtz.html calculations to match the runner length to your desired operating band but in the end without a dyno to test various runner lengths you're just shooting in the dark at a target even the automakers can't theoretically hit. Yes, even the automakers use dyno's to determine the optimal designs for their intakes.

http://www.physicsforums.com/showthread.php?t=80364

[Longitudinal]

Dahlback--ouch--second from the bottom in flow, second from the top in price.

[derracuda]

i see this two ways...

first off, we know the engine is a "vacuum", the pistons suck air on the down stroke.

under only vacuum situations, the manifold will behave one way. air is being drawn into the ports from every available "corner" inside the intake manifold.

under pressure, i believe it will act a complete different way. reason? one way it's being pushed through, filling cavities and voids, and will follow certain shapes and directions, the other way it's being pulled through and will not draw in all the same ways.... you all know that as long as the throttle plate is open, and the turbo is pushing air, the intake is being pressurized (duh) and the air entering the manifold isn't going to the exact same thing as it will under a vacuum. what it does under pressure i don't exactly know. the turbo should be pushing more air into that manifold than the engine can readily accept, correct? hence the pressure building on the boost gauge. that air is likely going to do something very different as the pressure builds and the air just stacks up in there, instead of just flowing along all the different shapes and contours of the manifold. i think anyone into audi's can tell you that a stock 3B IM is a very inconvenient design inside, and they are good for.... 600whp? so, i highly doubt my manifold is worse (but i could be completely wrong! it wouldn't be the first time)

if you watch my videos, the second one with the vacuum, you can see with nothing going on, the smoke falls from the top of the plenum at the slot to the bottom, and when the vacuum is turned on, it completely disperses the smoke and then draws it straight down(i thought that was cool). i made a channel to go under all 5 ports and did the same test, it draws in the same manner as just doing it from #5. under pressure, it pushes the air to follow the outer edge of the plenum and causes it to spiral in the middle. obviously it won't do that constantly under normal engine operation with the different cylinders flowing and not flowing and back pulses and such, but i don't think i can monitor that unless i find a way to have thick plexiglass ends and then use some kind of H2O injection to be able to see actual flow patterns under engine operations.

i would absolutely love to see this thing tested in real world conditions. so long as it doesn't hurt performance, i don't care really. it's a fun experiment and engineering challenge. i've never seen a design like mine, not to say it hasn't been tried, but hey! maybe i'm lucky and stumbled across something decent! maybe i just designed an intake that gives better flow characteristics and just increased power and the engines ability to make better use of the fuel. (Issam) are you going to tell me that i haven't? i never said i did, but it's all up in the air before something is actually tested in real world situation. even all the computer stuff isn't 100% accurate, though i do admit that it helps for sure to get an idea of what is most likely happening.

so, while i am mostly designing and building this thing from my head and crazy thought processes, i'm not ruling anyone's suggestions or critiques out completely

carry on the conversation as long as there is something more than "this design will not work" with no reasoning behind it. that's just useless banter. i want productive banter!

the flow chart you have Issam, doesn't quite convince me. it's just a *vacuum* flow chart. put each of those intakes on the same block with the same turbo(under pressure!), and tune it according to the 02 and egt feedback which will likely vary from one intake to the next due to their air distribution design differences. THAT is a real world test. i 100% said my tests in the videos aren't like real world, but they can give me someone of an idea of what's going on.


maybe i'll take this more seriously and have some kind of end caps milled up so that i can screw thick plexiglass to them so it can be seen what's going on, on a real engine. i don't have an engine dyno or real good ways to check this, so bear with me if #1. it doesn't happen, or #2. it takes a while

[Wizard-of-OD]

the flow chart you have Issam, doesn't quite convince me. it's just a *vacuum* flow chart. put each of those intakes on the same block with the same turbo(under pressure!), and tune it according to the 02 and egt feedback which will likely vary from one intake to the next due to their air distribution design differences. THAT is a real world test.

How about this....
MKIV GLI 1.8T with Garrett GT3076R.
Dahlback intake manifold = 2whp gain
SEM Manifold = 26whp gain

I spent alot of time and money testing plenums figuring out what works and what does not.Whether you are convinced or not D is not the issue.

[cuatrokoop]

Issam, flow benches do not give the whole story. You can't see what's going on inside, and you didn't even give pressure readings at the inlet and four outlets on that little spread sheet.

What did the torque numbers look like on that 1.8t? Area under the curve? Where did the increase show up? How's driveability?

[my2000apb]

Issam, flow benches do not give the whole story. You can't see what's going on inside, and you didn't even give pressure readings at the inlet and four outlets on that little spread sheet.

What did the torque numbers look like on that 1.8t? Area under the curve? Where did the increase show up? How's driveability?

yeah i would also like to know the pressure differences across the cylinders

[quattroking]

well, in the modified words of smokey the bear, you can help retroactively prevent dereks broken car by visiting the swapmeet section and perusing a long list of various goods that need a new home

hahahahahahahahaha. Good luck buddy.

[my2000apb]

Issam, flow benches do not give the whole story. You can't see what's going on inside, and you didn't even give pressure readings at the inlet and four outlets on that little spread sheet.

What did the torque numbers look like on that 1.8t? Area under the curve? Where did the increase show up? How's driveability?

WANTS MORE DETAILS...

[derracuda]

just out of curiousity, if anyone can tell me.... don't most rally cars have a good deal more torque than hp(like at least 50% more torque than hp), since the hp #'s are limited (correct?)... how do they produce that huge amount of torque which is very valuable in racing. everyone puts big turbos on, but rarely do i see dyno sheets with vast amounts of torque from way down low on john q. public turbo builds.