ITB M42

[*Glenn* 854]

Looking real good. Cold airbox next ? I hope that AFM is supported properly. They don't like vibration

[MLM 57]

Looking real good. Cold airbox next ? I hope that AFM is supported properly. They don't like vibration

Thanks Glenn.

The cold air box i had no longer fits but with a few mods it should be able to go back it. This acts as a support for the AFM, which yes is currently unsuported. I want to get that sorted and confident that the air fuel ratio is ok before being a daily drive again. I cant drive the car at the moment anyway so its sat there unused so there is no risk of damage.

[hybrid 1039]

Looks great! ..

You probably find it sounds a little like a e30 m3 with that setup. Lots of noise up high? under load that is..

right, next is extractors, exhaust, cams, remap, lighten flywheel and heavier clutch

then

stroker kit, high comp pistons, knife edge the crank, valves and carbon airbox with MAF delete and probably need a new ECU to handle it all.

it wants to sound like an angry beeee!!!

[MLM 57]

right, next is extractors, exhaust, cams, remap, lighten flywheel and heavier clutch

then

stroker kit, high comp pistons, knife edge the crank, valves and carbon airbox with MAF delete and probably need a new ECU to handle it all.

Funny you mention that...

This is whats spinning in CAD world at the moment. All still need more work (particularly the exhaust) and analysis.

If all goes well some of this may become a reality..

[JiB 0]

What CAD software is that? Looks like ProE? Looks awesome (you're my hero).

Btw, what are you going to use for intake/exhaust analysis? Ricardo Wave or similar?

[MLM 57]

What CAD software is that? Looks like ProE? Looks awesome (you're my hero).

Btw, what are you going to use for intake/exhaust analysis? Ricardo Wave or similar?

Yep its Pro E,

For intake analysis I only have ANSYS available to me which will give me an indication if my designs are an inprovement in flow /distribution etc over the plenum provided. To get an handle on pulse tuning for both intake and exhaust I am designing to published guidelines and ruels of thumb.

Just had a quick look at Ricardo Wave.. looks interesting..

[MLM 57]

Ok as part of this project i wanted to learn as much as i could , now I can add CFD analysis to the list of things.

On the left is the current plenum camber and the right one i designed to replace it. This is my first attempt at this so al I can conclude is the new design is better in terms of flow distribution across each runner although I cant say how close my design is to optimum. But an inprovement is an improvement.

Equal pressure at equal velocity indicates even air flow, you can see cylinder 4 of the current plenum (far left runner on each) has a higher velocity and pressure indicating this cylinder would run lean compared to the others. Not great. where my design seems to offer a more consistant pressure and velocity across each runner.

This officially concludes I am a geek..

[Apex Effects 3]

a geek with a mint running engine wish i my plenum was that cool

[hybrid 1039]

How hard was ANSYS to use ?

[MLM 57]

How hard was ANSYS to use ?

I will say reasonably easy for a program of that type. Quite similar to COSMOS works etc in setup.

I am new to it however so I couldnt say with any confidance how close what I am doing is to the real world rather I can compare one system to another to see differences under the same conditions. With any of these programs your answer is only as good as the input values you provide.

[DRTDVL 0]

You where commenting that your mesh sizings had a very large impact on your results...

If you want to we could throw solidworks on my grunt box at work and crunch out some small mesh.

[hybrid 1039]

I will say reasonably easy for a program of that type. Quite similar to COSMOS works etc in setup.

I am new to it however so I couldnt say with any confidance how close what I am doing is to the real world rather I can compare one system to another to see differences under the same conditions. With any of these programs your answer is only as good as the input values you provide.

For sure,

Very interested in looking into this for my own uses. Ultimately coming up with a bunch of models then even 3d printing a mockup and testing on a dyno runner legnth and camber size. I know its very hard to improve on stock without knowing what is what however this piece of software will point you in the correct direction atleast.

[MLM 57]

You where commenting that your mesh sizings had a very large impact on your results...

If you want to we could throw solidworks on my grunt box at work and crunch out some small mesh.

Im able to run smaller mesh sizes here. Will send pics when its done. Also will simulate a depression in the middle to increase pressure over 2 and 3 as you mentioned and a taper decreasing from 1-4

For sure,

Very interested in looking into this for my own uses. Ultimately coming up with a bunch of models then even 3d printing a mockup and testing on a dyno runner legnth and camber size. I know its very hard to improve on stock without knowing what is what however this piece of software will point you in the correct direction atleast.

Exactly, it is a great indicator of impending blunders. Producing FDM's of chambers would be awesome though hugly expencive (unless of course you have access to a machine). That stuff works out at $1 per gram roughly, more for SLA which gives a more useable part.

Starts turning into a F1 style build up though..

[hybrid 1039]

Exactly, it is a great indicator of impending blunders. Producing FDM's of chambers would be awesome though hugly expencive (unless of course you have access to a machine). That stuff works out at $1 per gram roughly, more for SLA which gives a more useable part.

Starts turning into a F1 style build up though..

For sure .. I have it on good authority about using chinese sources to do the 3d printing.

[MLM 57]

A minor update with pictures...well "virtual reality"? ones at least!

Plenum design is complete except a few minor tweaks, this is what i intend to build.

Design features staggered and angled bellmouths. This proved to give the best flow from analysis. Not 100% perfect yet but one heck of a lot better than the current chamber and alot better than my initial "best guess". Interesting how what you think would be ok turns out to be deficient even when comparing to factory designs. A few more tweaks and it will be ready for manufacture.

And finally a Innovate LC1 arrived in the mail today. I chose this to allow me to read and record my air/fuel ratio to see how things are performing and for the flexability a LC1 offers. Such as the ability to interface with a Link ecu. .

EDIT: spelling.

Edited August 30, 2010 by MLM

[dubman 39]

Nice work, very keen to see how this goes. will be good power output for a 4 cylinder.

[MLM 57]

Innovate LC-1 Installed over the weekend.

Cruise Air fuel ratio is approx 13.4 while wide open throttle is between 13.4 up to 15.6 which is quite lean. General beatling arround though is acceptable.

The unit is installed under the center console with the data logging and tuning cable accesable through the glove box.

[MLM 57]

Minor update:

Link G4 storm arrived yesterday, and CNCing of the air box mold jacked up as well. Slowly preparing for a summer holliday in the garage..

[thorburn 120]

Are you using the design you last posted?

What will the airbox and mold be made from?

Is the mold going to be multiple pieces? any chance of seeing how it is going to go together

[MLM 57]

Are you using the design you last posted?

What will the airbox and mold be made from?

Is the mold going to be multiple pieces? any chance of seeing how it is going to go together

Yep essentially the same design, just a few tweaks to dimensions and surfaces to get things sitting right, but more or less the same.

I am planning to make the chamber (dark bit in above pictures) from fibreglass using a mdf mold. The plan so far is to create two halves with a flange, these will be joined then the flange trimmed off and smoothed. I will post as I go. Its the first time I have done anything like this so we will see

The light grey bits will all be aluminium, I expect this to be the most challenging bit as my machining skills are less than admirable again we will see how i go!

Should both parts work out they will be joined by a yet to be decided method, maybe toggle catches or similar.

Nothing like diving in the deep end...

[Jacko 2076]

New Plenum looks kick ass!

[kingkarl 136]

This is the sickest project.

I love the accuracy and science you're putting into it.

[nastnas 9]

pretty CAD pics are wicked! just a few things to bear in mind. i think the air speeds will be higher... so watch out for losses.... also, since you've gone sooo deeep i would say build a 4 MAP sensor for each runner, as with ITBS the tuning is quite difficult. it took me ages to get my car right, and a 4 MAP sensor set up would of helped alot, but it never happened....

in your pics, how are the pressures defined? which parameters did you set them to and which are the interpolated values? as 0.4kpa deltaP is pretty good, have you simulated the deltaP of air coming though at atmospheric as i know with my ITBS it spent all its life taking in atmospheric pressures... hahaha

cheers mate... and its looking pretty wicked!

[MLM 57]

pretty CAD pics are wicked! just a few things to bear in mind. i think the air speeds will be higher... so watch out for losses.... also, since you've gone sooo deeep i would say build a 4 MAP sensor for each runner, as with ITBS the tuning is quite difficult. it took me ages to get my car right, and a 4 MAP sensor set up would of helped alot, but it never happened....

in your pics, how are the pressures defined? which parameters did you set them to and which are the interpolated values? as 0.4kpa deltaP is pretty good, have you simulated the deltaP of air coming though at atmospheric as i know with my ITBS it spent all its life taking in atmospheric pressures... hahaha

cheers mate... and its looking pretty wicked!

A 4 map sensor would be a good solution, The link I just bought though wouldnt handle it though unfortunately. I do have the option of TPS and or MAP to play with so that should produce a tuneable result...I hope!

The model to determine air flow pressure was defined as atmospheric pressure at the plenum inlet and .5 atmospheric at the runner outlet, ambient temp all walls. The actual final values are not worthy of close scrutinizing as I was looking at flow balancing and tended to look at the trends produced from various design iterations. Therefore the absolute values are somewhat pointless. When doing this I did comparisons between max theoretical air flow and max velocity to reveal any shadowing or unwanted turbulance.

The only real conclusions you can draw from the anaysis is that what i have designed is better than what currently exists in terms of even air flow per runner. Hardly F1 stuff but helped me reach a good solution.

Hope that explains it, this is all new to me so I cant claim to know even the half of it!

[MLM 57]

Labour weekend offered a bit of time to work on the car.

Laminate some reclaimed MDF from the skip at work to make blanks for plemum mould. Now awaiting time on the CNC router

Removed entire engine wiring harness , no wires cut so it slots back in. Next remake loom with Link G4 loom.

Grabbed parts of a harness from Pick a Part to make new loom. Aim is to retain the data link connector and the ability to reset dash lights etc.

Also started making a 4 channel igniter box as a experiment and as its, so far at least, a 10th of the price of buying a 4 channel igniter new. will see how that works out. Pics of this soon.

And had a wee experiment with a coil on plug kit using the existing coils and 325 ignition stalks. On the fence at the moment as to whether this one will work or not. Might revisit it later once its all runing again.