Thread: what Air flow meter

If it is a 3.5 you will need a flapper style afm with your ECU as well as a backfire protector valve in the air intake if you want the gas to run as well. Otherwise the afm will be damaged beyond repair with the first backfire.

All the injectors will be stuffed. It takes about 12 months only of gas-only driving to ruin the injectors. Find a set off a wrecked engine or source a set from the UK. I found a set for my big brother's '86 off a similar aged Rover 3500 saloon.

If you want to run the engine without the flapper afm you will need an aftermarket ECU such as Haltech but don't expect it to be cheap.

my 1990 RR 3.9 had a gas-only conversion when I bought it, I reinstalled a petrol tank (3 actually), the injector O-rings had all dried up and leaked a gallon of petrol over the motor when I first tested the fuel pump. All the injectors had completely gummed up; I cleaned them all out (quite a job) and replaced the baskets in them, achieved good spray pattern on all of them and the motor now runs very well on both fuels.
And yes, you will need a flapper AFM. The car will not run on petrol without the electronics to control the injectors. You could build a megasquirt system if you are short of hobbies.

Hey, thanks for the advice. I orderd the Air flow meter from the uk after giving them all the details. and they supplied me with the later type one. very anoyed. so i will order the flapper one now. I learnt a trick today on how to check the pulse to each injector. you use a small 12 volt globe and pull the plug to each injector, fit the globe in the injector and it will light up when pulsed, do this to each injector. I will keep you guys posted when i get it going.

cheers
will.

I have a full 3.5 injector system I have replaced with another for sale
it has been fixed and ready with ECU and the last plapper I could find in Aus PM ir you are interested

OK guys, I have had some time to pull things apart. I did actually get a refirbished ECU and Flapper AFM so now it is the injectors that need some attention. I have pulled the fuel rail and injectors out and tested them and they click when energised and they all read 2.4 ohms so i guess they just need a clean out as they have alot of carbon build up. Can i just get them serviced at a EFI mechanic??? and how much should i pay for each injector to be serviced, as i see i can buy new/refirbished for about 80 bucks which times by 8 is pretty pricey. I also read someware that early ford EL injectors fit the same, can any body confirm this.

Cheers
Will

Flapper style injectors are also fitted to VL commodores and skylines of the same era (mid 80's). EL Falcon is 10 years later and not compatible with flappers.

Another option for you guys is to convert to Ford EECIV control.
They are plentiful, low cost and far superior to the Lucas stuff and there are many options for recalibration. The Mass Air systems are sequential and have stereo HEGO's. So, apart from the increased reliability of the system and better fuel control you also pickup much needed ignition control which also goes a long way to improve both performance and fuel economy.
In fact the hardest part of the conversion would be the adaptation of the Ford TFI-IV distributor, something I embarked upon but gave up on because the engine stuffed up so have since commenced a 351 conversion.
Of course you could also adapt direct ignition, in which case(if sticking with the 5.0L EECIV) you'd only need to adapt the 8 tooth encoder wheel and pickup into the distributor.
You can in actual fact get any V8 running surprisingly well without any electronic programming if you use the right bits. I used a 5.0L EECIV, 70mm MAF and 30lb injectors on my 351 cleveland for many several years with great results.
These days I use a Moates quarter horse which allows real time programming and data logging at 2000 frames/second and it's only $250!