Papez

What, it never happened to you? It happens here quite often with ignition cables (luckily, Felicia doesn't have any :D), and bonnet insulation, which seems to be tasty for certain animals (martens and mice). In this case, bunch of cable was missing near firewall, where it diverts from main harness and passes to interior

I had SP-EL sensor and it worked well for about four years, until something ate wires to computer... It looks like damaged cable or bad pin contact

They didn't think, they just took radiator straight from Estelle. It worked in Central Europe, they didn't think about export to tropical countries or even such luxury, which is AC. Anyway, I'm not sure if it was mentioned earlier, but did you have original Skoda radiators or some Chinese replicas? Chinese ones have limited cooling capacity, barely enough to handle summer in Europe on non-ac car.

Computer itself is indeed same, but sensors of injected fuel are different for BMM and MPI. In case of SP-EL sensor, there's even difference between 1.3 and 1.6 due to different polarity on injectors. 1.9 doesn't have any source for fuel rate, so consumption and range doesn't work on TC-6 - TM-3 is variant without these functions.

Modern cars have bonnet sealed all around and covered most of the engine bay from the bottom and don't have problems. Maybe your mod just lifted the bonnet a little, so rubber around ventilation inlet didn't seal properly? Or it could force fumes to high pressure area under windscreen, which pushed it back to ventilation? Did you seal the bonnet all around or just sides? What dust do you mean? in engine bay?

Airbox has been designed for 99HP 1.6 engine (you could see same design in Forman prototype). Intake is in front panel, well isolated from heat in engine bay. So I think that thas part doesn't need improvement.

thermostat would be needed for oil-air cooler, oil-coolant exchanger is cooled by engine coolant, which is kept at constant temperature - which means that it also helps with warming up in cold weather.

he said that there space between radiator and frame, i understood that hose goes around radiator to engine compartment. Problem with oil is, that it shouldn't be cooled too much - which could possibly happen with finned oil pan. I think that oil-coolant cooler would be absolute best.

I wouldn't be sure about that, air acts weird in rear portion of those cars. Models with radiator in back had issues with getting cooling air into engine compartment. Also, these old engines were running with different oil... I think that if finned oilpan was needed, they'd include it - apparently they knew how to make it with hose going around the rad?

And oilpan is already exposed to underbody airstream, so there's nothing to improve. For oil cooling improvement, it's probably better to use heat exchanger. What improvement do you mean?

Well, it's watercooled engine, so rad cooling=engine cooling. That engine has been designed to run in the back, so it already has plenty of extra airflow in Felicia. Maybe, by getting the duct more tight to make sure that all air from bumper is forced through radiator.

That won't help, there's already duct (or it should be there) between bumper and front panel, that directs air from bumper vents to radiator - air from foglight housing won't pass over it

I think that hole under the engine bay is big enough to get hot air out. If you have issues with overheating, you need to check your cooling system. If you don't have issues, but you want to improve cooling anyway, you can get larger radiator, for example from diesel model.

What do you want to achieve? Engine's inlet is under bumper bumper, so scoop is useless for that. And ventilation inlet is placed in spot with atmospheric air pressure, so scoop is not needed. Some racing felicias have engine inlet under ventilation grill, no scoop involved.

6U0698019 is for ABS, 23,71mm. 6U0611019 is non-ABS, 22,2mm.

@RicardoM Exactly. And Felicia has enough torque to generate most power between 5000-6000RPM, so for both maximum speed and acceleration, it needs to be kept there.

You need power both to accelerate and overcome drag. Engine torque alone is meaningless to describe vehicle's dynamics - Felicia 1.3 has torque peak at 2600RPM, but power peak at 5000RPM - best acceleration is achieved at power peak, because torque is multiplied by gearbox. 1.3MPI gearbox is actually quite good for performance - top speed is achieved around peak power at 5th gear (~170km/h @ 5000RPM). Torque drop around 5500RPM is just enough to keep power constant when switching from 4th to 5th. If you switched earlier, you'd have more torque, but that'd be lost in the gearbox.

Probably clogged vent tube. It's next to release arm.

Yep, that's right. Gearboxes are nearly identical, there are just some reinforcements around differential on the 1.6 and 1.9 casings. Oh, one thing, 40kW gearboxes are longer than 50kW - 1.3MPi 40kW has same ratios as 1.6, while post-facelift 1.3MPi 50kW is the shortest available. BTW, why do you need crankshaft position sensor? 1.6 camshaft sensor wouldn't work?

No, in 1.3, engine's flywheel serves as a triggerwheel.

Yes, but it won't work, because 1.6 flywheel doesn't have cutouts that serve for position detection. And 1.3 flywheel won't fit. I think I've seen kit for 1.6, which used modified crankshaft pulley and sensor mounted next to it. gearbox is not based on Favorit (which never had 4 speed gearbox), it's Trabant's design, it's just coincidence (probably due to centrally planned economies reusing same designs/licenses)

Yes, there are just some tweaks in maps for improved starts etc., otherwise, they are identical.

Yes, it is possible to mount the flywheel wrong way. Cutout with extra teeth should be on the bottom with 1st cylinder at TDC. The system fires two plugs at the same time, one in compression, other in exhaust phase. I'm not sure how it acts when it's in different phases, where electrical properties are different. You wrote earlier that you can hear solenoids in injectors being activated, that means that you should get some signals. Maybe your method of measuring is inadequate for such short signals?

Is it mounted correctly to the engine? Its orientation is critical for proper firing order.

It is 0.20mm for steel pushrods, 0.25mm for aluminium. Old Skoda engines had steel pushrods all around, so it was 0.20 all around. 135-6 engines have aluminium pushrods on intake valves and steel on exhaust, so it's 0.25 intake, 0.20 exhaust. Although, there is some info, that steel pushrods can be set to 0.25 at temperatures beyond 32°C to compensate for different thermal expansion.