What is the best solution to daily drive an e21?

[giorgio2g]

Hello to everyone, i am starting this topic cause i'm deeply troubled about my beloved e21 and i want to read your opinions on what is troubling me. I own an 1981 315 with some mods. Most notably are a 5 speed gearbox and a double 32 weber carb. I don't own another car nor i want or have the financial status to buy another. So i daily drive it and i really love the fact that i use it everyday. However lately i'm noticing that it's getting more and more inefficient so i think that i should change a few stuff under the hood. So here it comes, what would you do (or have you done) if you wanted to make your e21 more friendly (towards your pocket), to daily drive it? Before answering here are two more facts, a) I can't spent crazy amount of money on the car given my current status and b) due to local laws, switching to an an engine that is 2000cc or more is not an option.

[Wilmo]

Later M10's are delivered with injection. There are multiple build descriptions available. I established with an M10B18 from '86 and the K-jet injection and electric ignition, a Schrick 292: 1 liter on 10km. Now with the same engine and ITB's I get to 1:12.

This includes a rather binary right foot.

[giorgio2g]

Although i like the sound of carburators, apart the fact that the're inefficient, i have a hard time finding a car mechanic that knows how to adjust them. So turning my engine to injection sounds like a good solution. I've looked and i can find a 318i engine at a fair price. Question: Is it simpler (or better) to replace my entire engine with a 318i one or to take the K-Jetronic system out of a 318i engine and convert my engine to injection?

[giorgio2g]

There is a high chance that the 32 weber that's on my engine, is not suitable for my car. For starters the original solex was a single carb but a 34. Which means that unless i press the throttle to the floor, in order to have the full power of the 32/32, the car is weaker than it was as stock (and therefore it struggles more to move and that presumably increases the fuel consumption). Next it's the choke. Stock solex had an electric choke while my weber has a manual and i don't have a lever to control it (that would explain the problems that i have when the engine's still cold). I'm writing all these cause there is one more option that i'm exploring and that would be to replace my current 32/32 weber with a 34/36 DGEV. So i'm between replacing the engine with an M10B18 or replacing the carb. I'm leaning more towards the M10B18 cause carbs have another big issue which is getting more and more serious and that is, that there aro not many mechanics who can tune them anymore. Personally, right now, even if i choose to replace my carb, i have no one that i trust to do a good job, to install it and tune it. So any thoughts/advice on the above?

[Wilmo]

In that case I would go to a tuner and let him or her tune the carb. With the right nozzles it should give you plenty of power. The Webers are actually easy to convert from manual to electric or water based. All the parts are still available, new or aftermarket.

I have driven with a 32/36 and reached 7.8l on 100km on the motorway driving 120-130 in my stock 1.8 from a first series E21.