Powertrain

Robert hoists a powertrain from a Renault Fuego Turbo

Which Engine to use?

Should I use the one that came with it?  

54/1871 arrived with a very poorly transplanted Lotus Twin cam engine.  Sounds sexy, says Lotus on it, but it was not 'original' and the install was so bad it would have to be completely redone.  After looking into that bulky, heavy, expensive, troublesome, stromberg-carbed, 95hp engine I decided to sell it.   I found a willing buyer who really needed it and offered what I considered to be a very fair price.   I hope it worked out for him.

Which Engine was originally installed?  

This is a minor mystery, that was discussed on the Europa list.   Certainly, type 65 'federal' cars ship with 1565cc Renault engine type 821-30, while Type 46 (S1) and some or all non-federal type 54's shipped with 1470cc engine type 697-04.  Given the highish serial number (1681) of 54/1871's engine, it can be assumed that it shipped with 697-04, as the federal type 54s of the same period shipped with 821-30's with serial numbers in the two and three hundreds.

 So, which should I install?   

While tempted by the possibility of the Toyota 4age conversion, I finally decided to stick with Renault.  The parts are expensive, but the installation will be simpler and I will run into fewer fabrication challenges. 

This still leaves many questions as there are tons of variations on the 697/821/807/843 series of engines.  It can get a little tricky as there are some parts/gearbox compatibility issues.  

Where do I find a Renault engine?

The stock engine in the S1/S2 was either a 697 (1470cc) or 821 (1565cc) 'wedge' chambered engine. These were tuned versions of the unit supplied with the R16. They share the same basic block casting as do the more powerful 807 (1565cc) and 843 (1647cc) series engines which feature a "cross flow" head with hemispherical chambers. Any of these engines will bolt up to the stock gearbox, and most have the
correct bosses on the case for the engine mounts. I would look for a crossflow aka "Gordini" due to the significantly greater power. This narrows it down to an 807 or 843.

Here's the rub... In the Europa, the R12, R16 and  R17, the alternator and water pump were driven off the end of the cam at the flywheel end of the engine. In other cars, those accessories were driven off a pulley at the end of the crank, obviously at the other end of the engine. The background to this is that the R12/R16 were front wheel drive cars with the gearbox ahead of the engine. The R15/17 used the same or similar drivetrain components, but with the engine up front. In the Europa (with the stock chassis) there is insufficient space for accessories or the crank pulley, so simply finding an '807' isn't enough, it needs to be an 807 with cam-driven accessories.

Or you could convert one. The parts required to convert a crank- driven layout to a cam-driven one include a longer cam and a support bearing for it, the appropriate pulleys and bracketry to mount the alternator, and a different water pump. You need some cover plates and other bits as well. Remember that the basic engine casting and bottom end are the same for all models. Most of the parts used in these engines are shared, so you can mix and match to some extent, and this can get interesting as the engines were produced over a 30
year span, though there are some changes of course over time. Thus, you may find a 697 or 821 converted to TS or crossflow spec by substituting the correct head, cam and valvetrain, and you may find the same engine converted to or from crank or cam driven accessories.

If you want the 'Gordini", the best donor car would be a R16TS or R17TS. This engine is about as close to 'drop in' as you will find, though some of the cases don't have the correct bolt holes, and you will of course need to fabricate an exhaust. If you value low cost and simplicity over hp you could use a 697 or 821 from the R16, but with the stock induction, will have less hp than the stock S2. 

So, I accumulated some engines...    

Follow the next links to compare the various Renault engine models.

Renault Engine Comparative Data

Renault Engine Comparative Photos 

Below is a drawing of a 697 engine and 336 gearbox.