19 Years of Tin Snail - Back to normality

[Rocket88]

Hate the stuff. Makes horrible streaks. Also, a 2CV windscreen isn't aerodynamic enough, so the water just sort of sits about rather than beading away. Wipers work fine now, bar the lack of parking. I've developed a great sense of timing though.

 

 

 

 

 

See your point ref screen shape...................although I've used the stuff on old chod with crap wipers, and always found it works really well...........

[dollywobbler]

2CV wipers are pretty good, especially now I've got new blades. It's just the parking that's been the problem. And the completely worn out linkage before I fixed that...

[dollywobbler]

Big bore engine conversion is underway! One piston and barrel removed, then I looked at this lovely, shiny new one and decided I should probably have a cup of tea. It's so nice!

 

Only issue so far is that the oil feed pipes to the cylinder heads are quite rusty. I've had to order up new ones, as a failure of one of those would not be a good thing.

[LightBulbFun]

*stalks the Reg on the DVLA for Cylinder capacity change*   

[dollywobbler]

*stalks the Reg on the DVLA for Cylinder capacity change*   

 

It will be done, but the engine hasn't actually been finished yet. I haven't made it back into the garage and it's now sub-zero outside. Sod that.

[320touring]

So, down to brass tacks how much additional poke do you get for the capacity increase?

 

Does it mean larger valves/rejected carb etc?

 

Could imagine a decent % hike in power:)

[dollywobbler]

I'm not actually sure, but I'm not expecting to suddenly be setting my Michelins on fire. As well as increasing the volume, it ups the compression ratio too. At a guess, I'd say 35bhp. I think the 652 Visas were 38. But, it's the torque that should be improved most. 

 

The kit comes with larger carb jets.

 

Fitting the new pistons and barrels shouldn't take me long - I'll probably have that done tomorrow. What'll take longer is rejetting the carb and fitting a load of new gaskets, fitting new oil cooler unions, digging out better cowling, replacing the oil feed pipe, dealing with the rats nest that is the horribly butchered (mostly by me) wiring loom, maybe fitting 123 ignition (someone gave me one) and trying to get the exhaust to seal again. That's last one is always fun*.

[forddeliveryboy]

So, down to brass tacks how much additional poke do you get for the capacity increase?

Does it mean larger valves/rejected carb etc?

Could imagine a decent % hike in power:)

It depends on the camshaft lift and duration - yes, they were all meant to be the same but in reality something around a quarter on later cars weren't up to spec. There have been cases of people actually _losing_ power with bigger pistons and barrels, greater reciprocating mass and more friction (this is an engine whose tickover cycles in sympathy with an indicator on as the alternator has to work harder!), cam/valve lift and duration. But Burton are reputable and their stuff is generally good, so the parts themselves should be ok.

 

The Visa's 652 was a thoroughly re-engineered engine with different heads, an extra main bearing and other subtleties. Good material quality, too - Citroen also used incrementally better materials in Ami and Dyane engines too and steadily reduced the 2cv engine metallurgy quality as its end drew nearer. Seem to think DW has an old Dyane engine in this car.

 

Useless fact - the claim they'd changed head material quality to cope with unleaded fuels for the '86MY was correct, although not in the direction most assumed (although the valves remained the same).

[dollywobbler]

Yeah, I had originally thought of going for a full engine rebuild, with reprofiled cam yadda yadda by someone who actually knows what they're doing. Was struggling to logistically make it work, and thought it'd be more interesting for HubNut if I have a go at ballsing it up myself.

 

Starting to wish I hadn't started today though. Have had a proper wipeout this evening! It's taken me about three hours to feel warm again, not so much to do with the cold in the garage. I think my body just wants an actual rest...

[forddeliveryboy]

Would imagine a 21/24 carb would work well with bigger swept area - even better a 21/26 off a Visa.

[dollywobbler]

Would imagine a 21/24 carb would work well with bigger swept area - even better a 21/26 off a Visa.

 

Weber conversions are gaining in popularity. The shabby Ami I drove had Weber power (though it's now on twin carbs I think), as did the road legal race car I also drove. I'll see how it goes.

[320touring]

It depends on the camshaft lift and duration - yes, they were all meant to be the same but in reality something around a quarter on later cars weren't up to spec. There have been cases of people actually _losing_ power with bigger pistons and barrels, greater reciprocating mass and more friction (this is an engine whose tickover cycles in sympathy with an indicator on as the alternator has to work harder!), cam/valve lift and duration. But Burton are reputable and their stuff is generally good, so the parts themselves should be ok.

 

The Visa's 652 was a thoroughly re-engineered engine with different heads, an extra main bearing and other subtleties. Good material quality, too - Citroen also used incrementally better materials in Ami and Dyane engines too and steadily reduced the 2cv engine metallurgy quality as its end drew nearer. Seem to think DW has an old Dyane engine in this car.

 

Useless fact - the claim they'd changed head material quality to cope with unleaded fuels for the '86MY was correct, although not in the direction most assumed (although the valves remained the same).

Grand knowledge, many thanks for sharing.

 

Be interesting to see what happens - seems to be a combo of high quality components and good setup to really see the benefits then,

[320touring]

Yeah, I had originally thought of going for a full engine rebuild, with reprofiled cam yadda yadda by someone who actually knows what they're doing. Was struggling to logistically make it work, and thought it'd be more interesting for HubNut if I have a go at ballsing it up myself.

 

Starting to wish I hadn't started today though. Have had a proper wipeout this evening! It's taken me about three hours to feel warm again, not so much to do with the cold in the garage. I think my body just wants an actual rest...

Glad you're going down that route - fun to see the trials, tribulations and triumphs!

 

Do you have someone you can use to do a tune on the engine once new parts are fitted?

 

Would be interesting to see torque/hp overlay Vs standard

[dollywobbler]

Of course, it doesn't help that I haven't driven the 2CV for a few weeks, and I'm always driving other cars, so gawd knows where my benchmark is. 

[dollywobbler]

Glad you're going down that route - fun to see the trials, tribulations and triumphs!

 

Do you have someone you can use to do a tune on the engine once new parts are fitted?

 

Would be interesting to see torque/hp overlay Vs standard

 

Nah. Will be settling for guesswork and trial and error. There's not much you can adjust really. Factory settings for most stuff, and the only way to adjust carb mixture is with jets. 

 

As for dyno readouts, do they go that low?!

[320touring]

I'm not actually sure, but I'm not expecting to suddenly be setting my Michelins on fire. As well as increasing the volume, it ups the compression ratio too. At a guess, I'd say 35bhp. I think the 652 Visas were 38. But, it's the torque that should be improved most.

 

The kit comes with larger carb jets.

 

Fitting the new pistons and barrels shouldn't take me long

20%ish increase in power is not to be sniffed at, and starting with so little, I can imagine it'll be at least noticeable..

[320touring]

Nah. Will be settling for guesswork and trial and error. There's not much you can adjust really. Factory settings for most stuff, and the only way to adjust carb mixture is with jets.

 

As for dyno readouts, do they go that low?!

Course they do:)

 

Bonne chance!

[dollywobbler]

20%ish increase in power is not to be sniffed at, and starting with so little, I can imagine it'll be at least noticeable..

 

I'll try and at least get some piccies up tomorrow. Only got one piston off so far, but there's some fair evidence of blow-by on the skirt. Starting to think a boggo 602 kit would have made a difference! Also found evidence of a mahoosive exhaust leak on the manifold, which might explain why the heater was stinking. Not much sign of any head leakage, which is nice.

[forddeliveryboy]

20%ish increase in power is not to be sniffed at, and starting with so little, I can imagine it'll be at least noticeable..

An extra 7 or 8hp from one of these is hugely rewarding, it's best to start off with a known brisk engine with high miles when fitting new bits for the most bang:buck ratio.

 

If the cylinders and valves are sealing ok then twin carbs are probably the cheapest way of releasing the power from one of these engines but it's a time-consuming business, a pair of Mikunis works really well.

 

I once had a really fast stock engine in a red '85 Special and made a rhs swan neck, twinning the exhausts - it flew. Tried the same on another engine - made it slower. A really good camshaft is the key, just a bit of a pain to replace.

 

I wonder who makes those Burton-supplied pistons?

[Bfg]

.

For what it's worth., many years ago I fitted new Visa 650 barrels and pistons to my car(s) which I used with the Ami-8 Weber carb. (..and a simple jet swap in the secondary choke).  Aside from a routine de-coke I never touched the cylinder head nor the camshaft.  I did however prefer to use the earlier drum braked 2cv engines or those from the Dyane or Ami-8.  The 1980's 2cv engines always seemed relatively gutless and always tuned to run a little lean ..feeling as if they were de-tuned to cope with the then new emission laws.  

 

As I recall - the fitting of the 650cc barrels offered negligible improvement to top-end speed (perhaps just one or two mph ..which is to be expected considering the vehicle's aerodynamics), nor to engine pick up ..but there was a useful increase in pulling power (engine torque) - which made the car easier to drive faster and also smoother (..less gear-changes needed).  In my opinion it was well worth the cost ..for the improvement in mid-range acceleration, such as when pulling out of roundabouts and tighter corners, and overall nicer drive.   

 

I also machined one-third (weight) off the rim of the flywheel, which had negligibly adverse effect on tickover lumpiness, but which did quicken the gear changes, helping acceleration times through the gears ..so an overall slicker drive.

 

Together they are the sort of changes (together with electronic ignition) which made one ask "so, why didn't Citroen do this ?"

 

I also tried an engine with twin carbs on it, simply done.. using rubber sleeve on the cut off manifold tubes, but I never bothered with the choke.  The carbs got warm soon enough, so that was not really an issue unless in icy cold weather.  Top end performance improved but again with not much difference to the top end (perhaps just a few mph), but the engine felt more willing on motorways, quick A-roads, and around Castle Donnington.   The only problem I had was the carbs running dry around some corners and roundabouts, due to the sideways centrifugal force when used on a car (which lent out on corners - quite unlike a motorcycle).   Because of this, and aside from getting rid of the long inlet manifolds (..which are no flipping good when cold) - I can't say it was really worth fitting twin carbs ..for my type of vehicle use.  But I'd go for the 650 conversion and twin-choke weber carb any day.   

 

Bfg.    

[dollywobbler]

Mid-range grunt is certainly what I'm hoping for more of.

 

Sadly, work has been utterly ridiculous this week, I had to get the new tyres fitted to the Rover and then I just decided it's too bloody cold (currently minus five outside) so I've not even entered the garage today. 

 

Oh and advise for tackling the oil cooler union leaks seems to be pretty wait for things to snap, then cry. Excellent!

[PhilA]

Reading that, then reading about Zel's Xantia makes me wonder what would happen if the springing of the 2CV was re-engineered to work with the computer controlled Activa hydropneumatic system.

 

Phil

[egg]

Reading this just makes me want a 652cc Visa/LNA! (I thought I'd got that out of my system just by talking myself out of an Hélèna...)

[dollywobbler]

Reading this just makes me want a 652cc Visa/LNA! (I thought I'd got that out of my system just by talking myself out of an Hélèna...)

 

Now, I quite fancied the idea of an LNA with BMW conversion. Turns out someone has beaten me to it.

https://www.2dehands.be/autos/citro%C3%ABn/lna/citro%C3%ABn-lna-proto-443008992.html 

[dollywobbler]

Yeah, ok. I really do need a tidy up. 

 

Still, I'm getting there. 

 

That's the first piston fitted. You push the piston down just enough for the gudgeon pin hole to appear, oil on the pin and push it in. Sorted! Apart from one problem. The original pistons are held in with simple spring circlips that are just a curved piece of metal. The new ones require circlip pliers to fit. I don't have circlip pliers. A friend is currently searching his shed for his pair!

 

Once that's done, the barrel gets pushed down over the piston and home, and I can refit the cylinder head. 

 

Sadly, I reckon my chances of having this running again by the weekend are roughly nil. I still haven't replaced any of the knackered oil seals, still have to do the other side and neither head has been refitted yet. Furthermore, I'm off out with work stuff tomorrow, have a major work deadline looking and am out on Saturday. I think it's fair to say that the 2CV run out on Sunday is not a go-er. Bah. Sorry BrownNova.

[PhilA]

It would have a strange heartbeat if you fire it up with one big cylinder and one smaller.

 

Phil

[dollywobbler]

Well, that hasn't gone well!

 

I was expecting these oil cooler unions to be a pain. I was right. Annoyingly, the other one came undone just fine. Now, this is where oil was already leaking from, so I guess I could be kind to myself and suggest that the pipe already had a pinhole and was therefore already in a weakened state. A replacement is only £54 plus delivery too, so could be worse.

[PhilA]

Better you catch a fracture there now than at Ludicrous Speed.

 

Does it have an oil pressure warning?

 

Phil

[dollywobbler]

Yes. If it comes on at speed, that's yir injun deid.

[Fumbler]

Then you have a nice, oily, hot 652 or so CC paperweight that can weigh down many things.