MSefi.com read only forum (Jan.15,2018)

I've had problems running a VDO tacho from the low voltage ECU tacho output signal... it seems like the VDO gauge wants to measure the back-EMF spike from the negative terminal of the ignition coil.

If you already have the low voltage tach signal, you can build a "tacho booster"..... see this ...

Greg,

You've got it right..... 1+4, 3+2 paired together. It is important to get it right - i had it wrong and it made things difficult to tune, especially accel enrichments.

well you got a good deal then

If you can live with it for now, then you should be able to get them to work.... they'd be ok up top with a lot of boost, but down low they will suck pretty badly.

Best of luck

you'd have to be making about 600HP to need injectors that big!!

I've got 660cc/min (approx 60#/hr) injectors for my engine that I am expecting to make 400-450HP from, and even then I have got headroom added when i picked my injectors!!


I know my graph is a little interesting, but it is a fairly ...

well if the Mini Cooper S injectors fit your car, then they are.

I tried looking for info for your engine, but cant find it. Perhaps ask at some performance workshops to find out what suits?

Holy jesus!! 95#/hr!??!!!

You would have to be running some serious boost to need those!!

FWIW, i actually looked at using Delphi injectors in my 2.0L turbo 4cylinder engine, but I had them flow tested by my friend's performance workshop and found that they are rather unsuitbale for a small engine ...

First link is dead.

google is your friend.

http://www.helix13.com/mini/products/engine-intake

If its a stock engine, I would stick with injectors that are pretty close to the stock ones.

I havent been able to find if your injectors are top feed or side feed with some quick google searching, so you'll have to find that out.

This site has got to be the BEST on the internet for fuel injector ...

What type of engine are they for?
Turbo?
Supercharged?
What type of injectors do you need (top feed/side feed)?
What flow rate are you looking for?

The reason i put these questions to you is because the types of injectors used for a big V8 are quite different to what you should use for a smaller 4 ...

Marc,

Talking to my tuner, who deals with the MEC717/718 coils a LOT on aftermarket systems.... they say the coild can be run that low, but they are a tough coil and can happily take up to 3.0ms of dwell before starting to get into the danger zone of heat.

He recommended about 2.5-2.7ms of dwell ...

Lance,

A very commonly used coil, and cheaply available here in Australia, is the Bosch MEC717. It's often used in coil-per-plug aftermarket EFI systems, and is about AU$60 per coil.

Specs are:
L = 2.58mH
R = 1.0 ohm

Now there is a formula used to find the charge current, based on the spark ...

has anyone tried using a Toyota ESA type ignitor like from a 20valve 4A-GE or any other Toyota engine where VR signals go to the ECU?

Just wondering if these types of ignitors (ESA types) have dwell controlled by the IGt signal as per the VAST systems?

ESA ignitors usually have the following ...

also worth noting is that most Toyota engines POST 1986 that have factory ECU controlled ignition timing have two or more VR sensors inside the distributor.

Both VR sensors have their white wires (signal earth in factory config) wired together to a common signal earth wire.

No worries with the ...

Thanks for the reply Lance!

Yeah I understand all that the VR signal is arbitrary based on which wire you consider the signal - I've done a lot of work with aftermarket ECUs on Toyota engines with factory VR sensors. In particular Autronic and Wolf3D ECUs tend to want a (+to-) VR signal, but the ...

bump!! Nobody knows if the positive voltage of the VR sensor is supposed to go first?? Reading the Megamanual it describes it as going first, but the diagram doesn't jive !!

I've wondered the same thing myself, but I am yet to actually run my MS-2 (will be trying it tonight), so I will post up ...