Jump to content

DIY Fuel injection thread.


yoeddynz

Recommended Posts

  • Replies 2.4k
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Where'd you have it mounted and what orientation? They dont last long when tuning normally foul them but they can be cleaned a few times before going in the bin. The innovate range arnt known for the best temp control either so thermal shock is a problem. Also leaving sensor in not powered will kill it super fast.

Link to comment
Share on other sites

It's mounted quite far down, somewhere below passenger seat rails so plenty of distance. Angled upwards at say 10 o clock.

I think I'll need to tone down my idle strategy and try keep the revs down to help with the thermal shock thing.

I've never driven it while its been powered off.

However it currently turns on the unit with ECU power on, some people have suggested having it turn on with fuel pump so it doesnt pre-heat if you're sitting there with motor off.

I hadnt driven my car for maybe a week, then when starting it today the sensor went pooz. So maybe it was condensation or something + thermal shock of starting or whatever.

Might try the 14point7 unit but seems odd that you cant free air calibrate it. although its a pain it seems like a good idea.

Link to comment
Share on other sites

  • 1 month later...

Where did we get to with cheap fuel injection systems? Looking to EFI convert my fagna - can grab a junk yard manifold and hall effect dizzy easy enough. Just wanting to maximise economy and power out of this bad boy. 2555cc and it puts a massive 85kW to the ground. The later factory MPI ones do 102kW and 220Nm torque so hoping to get closer to that.

 

Fred, Ned??

Link to comment
Share on other sites

Some of power /economy may be down to head design and camshaft comp ratio etc..

the gains in just swapping a well tuned carb to efi may net some pretty negligible gains for effort involved?

Why not fit later 2.6 (or 2.4) gear from a mid 90's machine including ecu?

Link to comment
Share on other sites

EFI all the way if you ask me. My car now returns 10L/100km and is only tuned for WOT for drag day, and a little bit of auto tune for part throttle, and super rich at idle and just off idle so plenty more gainz to be had... And that was towing the teardrop and 3 days worth of food and booze for 3 people as well as all the other gear I packed.

I'm 100% on the EFI band wagon now that my starlet is converted... So much better already, and it's a pretty ahit setup still with a single throttle body and spark through the dizzy etc...

  • Like 2
Link to comment
Share on other sites

and I kinda want to avoid using a factory 80s ECU because Mitsubishi EFI wiring looms don't tend to be stand alone from the rest of the car - and given the car is auto the ECU will be expecting to be connected to an EFI specific trans computer too. Unless I have a complete parts car, I will have to buy an ECU, trans computer, complete wiring loom, distributor, air flow meter amongst other things from a wreckers. I figure it would be easy to just leave the carby trans computer in place (just needs to see TPS input) and use an aftermarket computer with map sensor that can feed a tacho output to the factory digi dash.

  • Like 2
Link to comment
Share on other sites

An old microsquirt. Cam wants it back though so we're gonna have a look at my hardware again this weekend, but at this point it looks like I'm gonna stick a microsquirt chip on my hardware and try use that. I don't wanna use Fred's stuff anymore and I know microsquirt works... Pretty sure you're not supposed to do that, but I will likely look into using speeduino on my hardware after that

  • Like 2
Link to comment
Share on other sites

Coz factory 90s ECUs are garbage.

Yeah the laptop tunable 90's ecu in my Mitsubishi is garbage, closed loop knock control, dual octane fuel and ignition maps with interpolation. Lean spool, anti lag (if you are that way inclined) speed cut blah blah...

should have binned it for a link g2 years ago.

But yeah phil appreciate that something map sense will be tidier than having to find a spot for an afm etc.

Im not saying don't do it just that it may not be as amazeballs as you expect. I looked at EFI for my mini but gains are minimal.

Link to comment
Share on other sites

Three things relevant-ish to this thread but off topic to what's currently being discussed:

 

1. I went to a Taupo trackday, went out for first stint and then came back in and checked the logs.
AFRs were good, everything running well.. Although, why is my intake only getting to 96kpa at WOT?
Has the bellmouth inside my airbox fallen off? 

Oh wait... Checks the Barometer and that's at 96kpa because the track is ~400m above sea level  :rolleyes:

Everything working as intended.  :D 

2. I've been running a Tomei copy adjustable FPR to get a higher fuel pressure, currently running ~70psi at WOT and have vaccum connected to reduce pressure when at low load... But my fuel pump sounds like it struggles a bit. 

I think I'll switch back to the factory FPR to simplify my fuel system and give my fuel pump a bit of a break.
I've already had a fuel pump fail when I've been quite far from home, not keen on round 2!
Maybe I should put the car on the dyno first though and see if there's any benefit to the higher pressure.
I think the way to go here is come up with a number first, then stick to that. "If it makes less than xyz HP difference, I'll get rid of it"
 

3. Something interesting regarding IAT, previously I've always had my IAT mounted somewhere ahead of the throttle body. 

When I had it mounted in a 3" pipe, as soon as you mash the throttle the IAT would change really quickly.

Then when I built my new airbox which has much lower airspeed due to big volume, the IAT responds really slowly. 

Since then, I've mounted it inside the plenum behind the throttle body, and have found that the IAT responds very slowly annnnddddd it consistently stays ~10-15deg hotter than before. 

I'm not convinced as to whether this is the plenum heat soaking the sensor and giving a falsely higher temperature, or whether this is actually more indicative of the actual air temperature after it's spent time in the plenum heating up on the way in. 

Since my air intake currently takes air from the engine bay rather than an external source, it may just be that the average engine bay temp rises over time and this is what the sensor shows.
It would be interesting to setup a compensation table relating to a surface mounted thermistor on the plenum, you could either prove that it's the difference or rule it out. And maybe a 2nd temp sensor just in engine bay to compare to haha.

Link to comment
Share on other sites

An old microsquirt. Cam wants it back though so we're gonna have a look at my hardware again this weekend, but at this point it looks like I'm gonna stick a microsquirt chip on my hardware and try use that. I don't wanna use Fred's stuff anymore and I know microsquirt works... Pretty sure you're not supposed to do that, but I will likely look into using speeduino on my hardware after that

Lets go spend some time tuning your car Ned! 

 

Get that fuel economy hhhnnnnngggggggg

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...