ITB's on my 1.6L

Ice, thanks for the info. I'm going to have to look up that equation. Runner length is definitely important but I can't go to long or I'll end up hitting the firewall.
 
Alright, once again I've stayed up too late for my own good (need my beauty sleep you know) but I've done some more research on these ITBs and I "think" I've learned a couple of things.

1) From what I've been reading and from what I've seen, it is better to run the injectors higher up on the runners than close to the combustion chamber. So my fears of not enough fuel entering the combustion chamber are unfounded. That being the case I'll be using my Mazda injectors in the ITB stock injector location.

2) Now that I'm not worried about injector location, it will be easier/better to go with a custom/semi custom IM so I'll be working that angle.

3) I'll be spacing apart the ITBs to better match the runners going straight into the combustion chambers.

4) I found a Metric Induction Wave Tuning Calculator online that will prove useful
 
The runner length equations are really about making a tunnel ram intake manifold, though should hold true for ITBs if you tweak them for the altered throttle area/runner diameter.

The plenum calculation should by rights work for either manifold design (itbs or tunnel ram), as should the ram tunnel pipe calculation. You need to work off effective throttle area (which is the area of 1 throttle*4, so nice and simple).

Bare in mind plenum calculation is a little bit of voodoo - runner lengths are easy to calculate, but plenum volume seems to be dependent on lots of different things. The formulas for calculating plenum volume are based on researching many "best guess" formulas and probably will require a bit of testing.

I should really update that spreadsheet one day....

that online calculator seems to do something very simillar to my spreadsheet - but the spreadsheet tells the whole story (optimum throttle diameter, optimum runner lengths for various orders of resonance, optimum plenum volume, optimum ram pipe diameter and length, etc etc) - but I would caution that I am not a mechanical engineer, and so grains of salt should be taken ;)
 
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Oh, I won't. Haven't had much time to work on it lately because of family obligations. Dad had knee surgery and the meds made him hallucinate. After that wife caught a nasty cold and had to keep her at home a day or two. I should be back on track right after Thanksgiving. Going to my local scrap yard and see what I can find for building materials.
 
Well no real updates were gonna go to a machine shop and have them make a custom manifold, making the oem one work will not be worth the trouble. Other than that nothing else hes been to busy with work but once any progress is made hell post it up
 
Stealing my post counts are you?!?! Nah, j/k. As speed said I've been kept real busy what with working OT and the baby on the way but hopefully I can hold on to some of that cash from OT to buy my supplies.

I need a plate of aluminum 1/2" thick or a bit less to start construction. I will mark out a template and cut it out myself and then get the runners welded. I contemplated using 1/4" thick (approx 0.5cm) aluminum to keep the weight down a bit but I'm afraid it'll be too thin and the heat will warp it. Any thoughts on this?

As far as an induction scoop. I have an old computer server case cover which seems to be ideal for this scoop. I'll take pictures of it later on this weekend but I was thinking of mounting it between the runners and the ITBs so I don't have to create supports for it. It's light enough that I believe it'll hold.

A question for the Haltech gurus:
Where would be the ideal place to mount the air temp sensor? I was thinking somewhere in the intake plenum (induction scoop) that is close to the mouth of the ITBs.

I have also acquired this which will help me in my endeavors!

imag1748.jpg


If nothing else I'm hoping to do a lot of reading over the holidays. I've been wanting to jump into installing the Haltech but I don't know the wiring well enough to just dive into it.

Oh and if anybody, by sheer dumb luck, happens to have a Haltech fuel map for a 1.6L ZM, I'd appreciate it if you tossed it my way. Highly unlikely but it never hurts to ask.
 
If there are any maps already done for the ZM im willing to bet theyd be turbo maps so useless for you to begin with, in regards to the location of air temp sensor id place it where ever it will read the hottest air induction temps, it should also be located just behind the air filter AFAIK.
 
I figured most fuel maps would be done for a turbo setup versus a non-turbo setup. I was just fishing incase there was another nut like me out there. Thanks for the input on the airtemp sensor.
 
the IAT, like most sensors, is used for fueling relative to a given value. It shouldn't really matter where it goes - because you tune with a wideband O2 sensor. The ECU itself doesn't overly "care" what the temp is - it just cares about the delta. That is to say, if you have the IAT in cold air, and you read a 2 degree change, you fuel accordingly. If you have it in a hot place and you read a 2 degree change, you fuel it the same way. The reading will be different but the result the same.

I'd place it where you get the highest amount of variability to give yourself the best chance of actually reacting to change in charge temp. If you place it in a location where its heat soaked you're not going to see a delta. If you place it out in fresh air somewhere you will get something you can use.

As for maps - make your own. Predefined maps *rarely* yield the best results, especially if you are doing something a little different. Tuning the vehicle yourself is a very rewarding experience and you'll learn a great deal about how things work.
 
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Yeah I wasnt suggesting he place it necessarily in a heat soaked area just the area thats going to report around the highest temps. My guess would be around cylinder 2 (from left to right).

But thats only a guess. My logic behind the hottest temps was in regards to clean combustion and safety. Whether this is failed logic im unsure :)
 
Yeah I wasnt suggesting he place it necessarily in a heat soaked area just the area thats going to report around the highest temps. My guess would be around cylinder 2 (from left to right).

But thats only a guess. My logic behind the hottest temps was in regards to clean combustion and safety. Whether this is failed logic im unsure :)

The logic seems relatively sound - but the absolute value of any temp sensor is pretty inconsequential...

The way I tune (and its far from the only way) is to chase air fuel ratios - so if i see a drop in air temp of 2 degrees on the air temp sensor, i should see the engine leaning - so at the whatever that temp value fuel site i'll push more fuel in until the AFR is back where I want it. The actual reading itself is pretty much pointless because what you are really looking at is the change in air temp.

Same goes for water temp sensors, oil pressure/temp sensors and so forth - you're interested in whether it is rising or falling within an observed norm, not that its 1% higher than what you think it should be...
 
Thanks for the input guys. I really appreciate it. I know nothing of fuel maps or installing FMUs but I do know computers and medical equipment that cost more than 4 times my yearly salary. I'm kind of nervous but looking forward to installing my own FMU.
 
No need to be nervous about installing it... just take your time. As someone who has been involved in several ECU installations, and plenty of street tuning sessions I can offer you a few words of advice...

1) Take your time. If it takes you a week to install it, so be it. The first one I installed was mine and it was a rush job - solding at 4am because your wife needed the car at 6am after having no sleep leads to mistakes, flat batteries, killed components, and a messy messy installation.
2) Buy a gas soldering iron - they are so much easier to use when crawling around under the dash of the car and easy switching from iron to heat torch for shrink wrapping is so much win.
3) pull the passenger seat OUT (!). You'll want the leg room so you can lay comfortably under the dash of the car without cramping. You'll probably be there for a while so spending 15 minutes tearing out the passenger seat is well worth the effort
4) make sure you have a multimeter which has a continuity tester and probes. Often wiring diagrams are confusing, especially when looking for things like constant voltage signals and so forth to wire into.
5) "easy mode" is running the full aftermarket loom through to the engine bay, cutting off the stock loom at the sensor and rewiring. This is far easier to manage/keep track of then trying to cut and splice into the factory harness but does lead to a messy install
6) "hard mode" is splicing/cutting/wiring into the stock harness inside the passenger compartment. With the exception of any "extra" sensors you want to run out to the engine bay, this leads to zero increased mess in the engine compartment for the ultimate "stealth" install... but BE CAREFUL if you do this...you can easily mess things up.
7) "extreme hard mode" is something i've only done once - with varying success - and that is to build a patch harness to allow easy swap backs to stock ECU. This uses nylon male/female plugs, crimps, lots more soldering and a requirement test every connection once they are made. On the car I did this to, we had problems for weeks tracking down phantom wiring problems. Car runs well now...if you're lucky the owner of the vehicle might come and give a testimonial to this method of installation.
8) Label everything. White tape and pen, put clues/hints/reminders everywhere.
10) be generous with your loom - don't cut things to exacting sizes...better to leave slack and wrap it up with some tape then stash it under the dash then cut short, screw it up and realise you've left yourself with no room to move. If you go with "easy mode", give yourself a good 4inches from the sensor to make your cut and solder.

when it comes to actually tuning it, remember safety first. Its far better to creep up on the tune from the rich side of safe, then it is to start lean and richen up. Leaner is meaner but it will kill things if you mess it up.

Tuning itself is always relatively straight forward. There are a pile of options for fine tuning in various ECUs but essentially you always have a 3D fuel map which plots fueling to load and rpm sites. Normally you have a 2D or 3D timing map which maps ignition advance to RPM and/or load sites... once you have it running, and the AFRs are good you can start mucking with things like cold/hot start, afterstart enrichment, afterstart ignition advance, dwell, injector phasing, transient throttle maps, water temp enrichment, air temp enrichment, deceleration maps and a host of other options that various ECUs will give you...but start simple - remember the engine requires fuel, spark, air and compression to run...everything else can come later once you have taken care of the basics.

I didn't intend this post to be a sermon.. just some encouragement, and some pointers to save you the pain i've suffered doing these sorts of things in the past. One thing i can't save you from is the inevitable soldering iron burns
 
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