This is actually rather poor tech information. His car does not NEED a calibrated maf. However it is the easiest and fastest way to make the car run.
My opinion on this matter is that you SHOULD get it tuned. Regardless of whether or not YOU think it runs ok. A tune will allow you to run literally any maf on the market, with any injector that is compatible with the pcm. A prime example of this is my car. I had trouble dialing in my fuel injector slopes, so I hooked up my stock maf and adjusted the slopes to their proper setting. Once that was done, I hooked my HPX maf back up, and tuned the MAF transfer function.
So yes, for about 3 days, i was running a stock F1VF 94-95 maf with my 900cc (83#) injectors.
As for the fuel boiling off due to having a large pump... I run a 416lph walbro in my tank. It runs 100% all the time, and is capable of supplying enough fuel for 900hp on pumo gas, or around 750 on E85. I logged my fuel temp in my return line. It was 12* warmer than ambient temp. Hardly something I would concern myself with.
Not always true. My stock 95 wouldn't idle after a cam swap w out a tune.Just like you don't NEED a custom tune
After following the zeitronix.com link, there are no installation instructions for the ethanol/gasoline sensor. It would make sense to install it in the pressure feed line, since it is more beneficial to know the temperature of the feed to the engine and not the return.
That plus the amount of fuel in the return line decreases as demand for fuel increases, This decrease in flow could cause erroneous readings on the gauge unit.
Flex fuel Sensor Technical Specification:
Measuring range: 0…100% Alcohol (ethanol) in fuel mixtures
Sensor Accuracy: 5% of the mixture ratio
Output characteristic: Linear
Operating temperature: Environment -40°C… +125°C, Fuel -40°C… +90°C
Maximum fuel pressure: 10 bar, (145 psi)
Maximum pressure drop: 0.1 bar, (1.45 psi)
Maximum flow: 200 l/h
Supply voltage: 6…18 Volts DC
Sensor Temperature error: < 1.5%
Response time: < 250 ms after power on at any temperature
Design: Suitable for the installation in motor vehicles, independent of position. Housing is waterproof. Always check for fuel leaks!
Makes sense to do it that way with coupled with the information in your post with pictures of your car.200 LPH flow capacity, and I run a 416 LPH pump. Do you see the flaw in your logic?