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Tuning Billancourt 845cc engine for power

Homegrown

Homegrown

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Someone made any attempts to make some more power.
I only see manifolds like in the link below.

Have someone done something like Webers, bike carbs, camshaft, porting, extractors, standalone fuel injection, or turbo.
I search a lot on the web but find almost nothing on the Billancourt engines.
I my nature I want to optimise cars with a lot of work and knowledge to a small amount of cash.
And no I stick with 845cc or tops 905cc Billancourt.
 
Putting a Renault 6 32mm Weber carb and mani on is the easiest way to get more poke.
The tubular Autobleu manifolds are not well made and require a lot of bashing and bending to fit, and I'm not conviced the HP gains would be astronomical.
You can get 60MM piston kits for a 845 from https://www.melun-retro-passion.com...am-60mm-embase-cuivre-625mm-axe-14mm-904.html .
ITB's or bike carbs may have been done but without modification to other parts will give you negligible HP gains - you may be able to get a rare Weber DCOE kit for a Dauphine G ...or even a Judson supercharger kit but those are like dodo teeth.
If you're going to the effort of turboing you may as well just swap a bigger engine in and be done with it.

Gasflowing the head to the manifolds with a bit of porting, skimming the head, fitting a 32mm carb, stainless mainfold back exhaust system and fitting a fast road cam is probably the best way to go.I understand you'd rather keep the Billancourt but there is a reason why most of the Dauphine boys swap 5 Alpine or A110 engines ... as tuning the 845 is a lot of effort for not much performance :/.
 
Jnr-Renospeed said:
Putting a Renault 6 32mm Weber carb and mani on is the easiest way to get more poke.
The tubular Autobleu manifolds are not well made and require a lot of bashing and bending to fit, and I'm not conviced the HP gains would be astronomical.
You can get 60MM piston kits for a 845 from https://www.melun-retro-passion.com...am-60mm-embase-cuivre-625mm-axe-14mm-904.html .
ITB's or bike carbs may have been done but without modification to other parts will give you negligible HP gains - you may be able to get a rare Weber DCOE kit for a Dauphine G ...or even a Judson supercharger kit but those are like dodo teeth.
If you're going to the effort of turboing you may as well just swap a bigger engine in and be done with it.

Gasflowing the head to the manifolds with a bit of porting, skimming the head, fitting a 32mm carb, stainless mainfold back exhaust system and fitting a fast road cam is probably the best way to go.I understand you'd rather keep the Billancourt but there is a reason why most of the Dauphine boys swap 5 Alpine or A110 engines ... as tuning the 845 is a lot of effort for not much performance :/.
Click to expand...
Thanks for answer Jnr-Renospeed
I have cars with a lot of power already (other brands).
The recipe you mention 32mm carb port and polish headers and exhaust will be minimum.
Camshafts I haven’t seen available.
I’m surprised there’s so little performance part for such a popular car comparing to the vw beetle and others. Almost nothing available.
I will stay with the Billancourt and see what can be done.
Building intake and exhaust is no problem so I do it myself.
Car is fantastic too drive but I think some more grunt to the smoothness it would be perfect.
Some times I have trailer behind.
If someone have any information of tuning the engine feel free to write and add links.
 
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CatCams may do camshafts for the Billancourt/Ventoux but I don't know for certain. Getting the standard cam reground is probably the easiest option.

And yes there is little to no tuning for normal Renault engines unless you go the Alpine or Gordini route ...
 
Search around for Dauphine 1093 version, this was the highest level of tune factory offered to the Ventoux engine.
It has been discussed here earlier:

tuning 845

I had the opportunity to drive a sixties honda a while back and it got me thinking about RPM. The s800 has a smaller engine than the 4 producing more than double the power. I appreciate it is a lot cheaper to pop a tx motor in but has anyone tried a proper attempt at raising the redline and...
www.renault4.co.uk
 
The Honda S800 had a 792 DOHC engine and benefitted from Honda's motorbike knowledge, hence why it happily revved to about 8,000 RPM. Its power curve was geared to being nippy and sporty, which is the very antithesis of what a Renault 4 is, so I don't think the comparison is valid. I'm sure a Renault 4 engine could be persuaded to produce a little more power, through carburettor jet changes, compression raising and ignition timing alterations, but not by revving to 8,000 RPM!
 
It's very interesting to read back through the threads relating to 845 (29bhp/41ft/lb Torque) tuning for more power, particularly the Honda S800 (4 cylinder/791cc/70bhp/48ft/lb). Back in 1974, I had both at the same time, so enjoyed the Honda's 8,500 RPM redline in parallel with the R4's day-to-day practicality.
However, the S800 was not a 'bike' engine, but had been specifically designed in the early 60's as a very efficient car/van(!) engine for Honda's first foray into the four-wheel market. It started as the S360(cc), then evolved to the S500/S600 developed to the final S800 that was marketed internationally from 1966-1970. Water-cooled, it had cast-iron wet liners (cast in pairs) within a die-cast alloy engine block with a roller-bearing crankshaft. Unusually for such a high-revving engine, it was long-stroke (60mm bore x 70mm stroke, compared to the R4's 58mm bore x 80mm stroke) fed by four Keihin carburettors (2 x twin choke, similar to Strombergs). All this sophistication, combined with twin overhead camshafts (8 valves) and a four-into-one. tubular exhaust manifold, was light-years ahead of the opposition.
Which did I prefer to drive? I enjoyed both for different reasons, but the Honda's 12mph/1000 RPM could become tedious on the motorway. I much preferred the R4 GTL upgrade in 1980 to 1108cc (70mm bore x 72mm stroke/34 bhp/54ft/lb torque), which enabled much higher gearing for far more relaxed long-distance driving. Revs are all very well, but in my opinion the GTL five-bearing crankshaft and larger engine capacity is a better starting point for power, and most importantly, more torque.
 
angel said:
Search around for Dauphine 1093 version, this was the highest level of tune factory offered to the Ventoux engine.
It has been discussed here earlier:

tuning 845

I had the opportunity to drive a sixties honda a while back and it got me thinking about RPM. The s800 has a smaller engine than the 4 producing more than double the power. I appreciate it is a lot cheaper to pop a tx motor in but has anyone tried a proper attempt at raising the redline and...
www.renault4.co.uk
Click to expand...
Thanks for all answers!
I read most information available in English about 1093 and tuning, as well all in this forum.
Surprised there is no parts for tuning engine or chassis.
If compared to the Mini engine witch is similar in construction there is lots of trick and tips how to port, tune, headers, carburetors, etc.
I checked the ports on intake and exhaust and there are a lot of things you can do to reduce turbulence and get more laminar flow
 
You may improve flow in the ports, but valves are small and rather shrouded by the combustion chamber. And the fact that there are no individual inlet ports limits carburettor choices.
 
angel said:
You may improve flow in the ports, but valves are small and rather shrouded by the combustion chamber. And the fact that there are no individual inlet ports limits carburettor choices.
Click to expand...
Thanks for input!
1093 tuning is old school due to FIA regulations but I check some work that a Danish guy made.
The intake port look really bad so I will reshape some areas. Will fill long radie with JB-weld and reshape (area expands for no reason under valve seat to disturb flow) otherwise mostly a clean up. Everything for improved gas flow. Not bigger but smoother and flow friendlier is the concept.
I will add three more pinstuds for the intake and exhaust manifolds to assure exhausts stay in the pipes.
As long as I stay with 58mm bore valve curtain are is catastrophic but have to live with it.
Feel free to come with input positive or negative

755DD88E-72B4-4179-A40A-26A3E8EAE800.jpeg
 
Now that you have stripped the whole engine down, it's worth finding true TDC, checking camshaft timing and set it as required. It's rarely checked on such engines - most people simply line up the marks. It's impressive how much can spot-on camshaft timing affect engine performance.
 
angel said:
Now that you have stripped the whole engine down, it's worth finding true TDC, checking camshaft timing and set it as required. It's rarely checked on such engines - most people simply line up the marks. It's impressive how much can spot-on camshaft timing affect engine performance.
Click to expand...

What I can understand there is no possibility to adjust cam timing at all except one chain link back or forth. All sprockets have fixed mounting points.
Thanks for input.
 
Checked intake side today and carb is Solex 30/35 PDSI(T) with 35 mm trottle.
Maybe reason why I felt bit stronger than what it’s supposed to.

1A2669DD-C8A9-4E33-B60D-86A97950AEE7.jpeg E7EE3920-D4F6-4D2F-B017-70120BD3A4CD.jpeg
 
Carburettor is probably a VW Typ 3 part, they were fitted in pairs on the flat four engine.

I would adjust camshaft timing by omitting the woodruff key on the camshaft. Interference fit of the gear backed up with a bolt - as you have already tapped the camshaft end - is more than enough to hold the gear.
 
angel said:
Carburettor is probably a VW Typ 3 part, they were fitted in pairs on the flat four engine.

I would adjust camshaft timing by omitting the woodruff key on the camshaft. Interference fit of the gear backed up with a bolt - as you have already tapped the camshaft end - is more than enough to hold the gear.
Click to expand...
Carburettor is a generic Opel carb. They use Solex30/35 PDSI(T) on 1.1-1.7 litre engines under long period. I guess 1.1 litre version can be quite good start setup for small Renault engine.
Not sure how common Opel is in your countries, guess GB mostly had Vauxhall. In Sweden Opel propably was top five selling brand in the 70-ties.
 
I recall the 35PDSIT on the Kadett D had a large torsion spring for throttle return, yours may be from a RWD Opel.
Opel was very popular here, too.
 
El Alesito real said:
YES, we did it...Here in ARGENTINA That engine was the GOAT in our Formula 4 Class...
Attached PDF is what street racers from the 60s used to do to that marvelous engine... The languaje is pretty gangsta, but I Hope It Helps
Click to expand...

Big thanks!
Have to try to translate it to english/swedish so I can get use of it :clapping:
Edit My wife showed me an app that translates spanish to swedish very convinient

best regards from Sweden.

PS if you have more information please show it to us DS
 
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