EFI conversion

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Re: EFI conversion

Post by wurlycorner »

Love the car... Drives like a complete knob though, as you say...

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Re: EFI conversion

Post by xantia_v6 »

Mandrake wrote: 12 Jan 2018, 13:20 Wonder what happened to that car as these videos are over 10 years old now...

The registration number comes up as invalid or cancelled on the LTSA site, so I presume that it has come to a sad end.
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Re: EFI conversion

Post by Mandrake »

xantia_v6 wrote: 12 Jan 2018, 21:01 The registration number comes up as invalid or cancelled on the LTSA site, so I presume that it has come to a sad end.

Pity, but not unexpected. I'd say it either blew up, or he got bored of the project and moved onto something else, as his youtube channel suggests he is into all sorts of car related shenanigans and this was just one of many...

The problem with trying to turbocharge an air cooled motor like this to twice its original power is that there isn't a lot you can do to increase the performance of the cooling system - it doesn't look like he even supplemented the standard crankshaft fan with an electric fan - and you can't easily monitor the cylinder temperatures either to see when they're overheating...(perhaps you could measure the oil temperature before the oil cooler to get an estimate)

So my guess is it ran fine in short bursts like the dyno or tearing around the block but a long hard run overheated and destroyed it...or maybe it crashed! :twisted:

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Re: EFI conversion

Post by Zelandeth »

Singe point injection systems can work very well if properly set up, and I'd say far better than a carb in anything other than absolutely top-notch condition that's been tuned on a rolling road etc.

Grafting a system onto a car that's never been designed for one isn't a small undertaking, but it's certainly not impossible. If the car normally has a single carb it's *relatively* easy...for twin carbs I reckon you'd probably be easiest to look at a multipoint setup which will need the inlet manifold modified to accommodate the injectors.

A single-point system to go onto a single-carb car is pretty easy. Just need to find a throttle body from an engine with roughly the same capacity and have an adaptor plate machined, plonk it in the place of the carb and make sure all the appropriate sensors are available. Make sure to think about this carefully, as you may find that you need to look at fabricating brackets etc.

You're probably going to need a custom ECU though (i.e. Megasquirt). Biggest headache with grabbing something from a normal production car is that one of the main parameters that most EFi systems use to control mixture is coolant temperature - and of course if you're talking about an air-cooled engine that's not going to be available. An ECU with customisable maps though should be easily able to set up to use oil temperature instead though.

I'd suggest a setup that also uses a lambda sensor in the exhaust system simply because it gives the ECU a much "better picture" of what's going on and should give finer control.

Emissions shouldn't be a problem in any way, shape or form as if set up properly it will run far cleaner (and more consistently) than it will on the carb.

Having done this on the Lada (in this case it was relatively easy as it was injected from the factory on later models, so I was able to grab the entire system from a donor vehicle essentially), I'll say it's definitely worthwhile. It really has totally transformed the car and made it far more usable.
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