Looking for engine information

[LeBlanc]

Hello,

I'm looking for more information on the engine that was in the 1969 R4 that I bought recently, and am restoring now. The engine that was in had a type plate reading "B1BS070" and "RH2096".
On a french forum I found an overview of the R4 engines, but this one isn't in there. There is however an B1BS707, so I guess is a type error ? That would be a 1984 onward egine, so not the original
Attached I put some pictures, maybe someone could shed some light on the exact type of the engine, and the car it should have been put into.
I've bought recently a 1967 engine, which is a bit lower in power, but an checking it's health to see if it would live nicely in the '69er..
Thanks for the advice !

 

[angel]

You are right the B1B a very late (84-86) 845cc engine. It should have a Zenith 32IF7 carburettor (it is not visible on the photos), combined with the vacuum advance distributor this setup makes a very sweet and torquey 845.
Amazingly enough they kept the correct for '69 334 gearbox and metal four blade fan!

 

[LeBlanc]

Thanks Angel for the info..

I think I will keep this engine in the car, although it's not really the original one, but when one turns up one day, it's not so much work to swap it I guess.
I've got no idea about the km's (or miles) on the engine, so not sure about the state it's in.
I did a compression test on the 4 cylinders and got measurements between 8.5 and 9.5 kg/cm2, or 120 to 135 psi. Is this a normal tolerance or should I get the pistons overhauled ?

 

[angel]

They seem good, although I have never seen any published compression pressures for the small engines (by the way, has anybody any info on this?).
The pistons/rings/cylinder liners on these engines are very long lasting, so I bet they will be fine (especially for such late production engine).
Try to make a leakdown test too, it can be more helpful than a compression test.