Is this normal? Duratec content. Could be boring for some.

[myothercarsa2cv]

10,000 rpm on a 2CV engine... Probably not advisable! The Guzzi has the con rods on the same journal, right? Not so on the 2CV... If you put a camera in the case and watched the crank as it revved that high, I suspect it would look like a banana!

[AMMO]

Thanks Dr. Slotter for the additional information. Nice to hear from people in the know who are actually involved in these things rather than the second hand snippets I get. Any stories or anecdotes you can share?

 

I had a friend who now works for Lotus that used to work for a company called Scott Gibbin. They did testing on on the Cosworth Sierra turbo engines. They used to get the engines up to temperature and at maximum revs dump 200 gallons of cold water through the cooling system to see if they could make the head gaskets pop. Done any similar nasty things to engines in your work?

 

The crank on a 2 CV is a pressed together affair. A one piece crank would be an improvement but what is likely to limit the rpm capacity to rev is the cylinder head. Anyway going the one piece crank route is likely to be expensive. If it were my engine I would look at what can be done to improve the standard engine. I'd be looking at something like 50 bhp per litre, so around 30 bhp perhaps?

 

I had a Guzzi V50 when I lived in Shepherd's bush in the early 80's. I would commute to work to my job as a workshop manager at a place called Motomecca in Clapham. I thought it would be a good idea to tune the little Guzzi. I ported the heads and had a cam ground, I think I even stuck bigger carbs on. The result is the the bike had no bottom end, wouldn't tick over and was generally a pig. I had to raise the float levels in the carbs so it would run at all. No gas velocity at low rpm. The one thing it did do well was rev. The power band started at 6,000 rpm and went on to 10,000. I did my own form of destruction testing every morning over Wandsworth bridge giving it the berries knowing that if I blew it up I could get someone from work to pick me up. Never did manage to break it. I later sold the bike to a guy on the Isle of Man who stuck a standard cam in it and and went on to do many miles more.

 

The moral of the story is don't stick the cam profile for a 1,000 cc engine into a 500cc one. I've done a lot more work on small cylinder capacity engines since and have been more conservative on the duration figures.

 

I'm really interested in having a look at the 2CV to see what sort of potential it has. Maybe a few of you 2 CV freaks could get together to fund the project?

[myothercarsa2cv]

Quoting AMMO: 

...

 

I'd be looking at something like 50 bhp per litre, so around 30 bhp perhaps?

 

...

 

I'm really interested in having a look at the 2CV to see what sort of potential it has. Maybe a few of you 2 CV freaks could get together to fund the project?

 

I'm already at a tad over 30bhp (standard was 27bhp ish) according to the rollers in Tewkesbury (that was a while ago, though, and I'm pretty sure the engine needs a bit of work done on it now ☹️ Though it's still a quick ol' 2CV) - that's with 9:1 CR (up from 8.5:1), cold air kit, electric ignition and uprated coil. You can get wasted stem valves off the shelf, and the older engines had double valve springs that (if you can find them) are a popular upgrade for tuned engines. 610cc rebore kits exist but are hens teeth. You can also buy gas flowed heads, which are flowed the same as the 24hr race engines. Other bolt on parts are a Kent race cam, but it just bumps the power higher up which is useless for road driving. Burton in the Netherlands are in the process of producing a turbo kit (there's a video on Youtube of their test mule destroying a Golf). No idea on power though. Loads of Heath Robinson mods out there, including using Smart Car turbos, fuel injection...

 

As much as I'd love to get cracking on a bit of development, I am trying to save for the next house deposit... ☹️ Boring, isn't it? One day, one day... I'll have to start collecting parts slowly but surely...

[AMMO]

Sounds like you've already done the first easy stage then. The next phase is going to cost money. Looks like you are in the same boat as me with the 2CV as I am with my Duratec. Frustrating waiting years to do stuff you want to do but can't afford to.

[myothercarsa2cv]

Indeed, but you seem to be making progress with the 2L project, which is good Keep us up to date 😶‍🌫️

[AMMO]

More talks with the engine designer regarding my new crank. Discussed BMEP figures and maximum rpm. He's ex-Cosworth and mentioned BDA's so later yesterday evening I dug out a book on Cosworth engines I had bought in the 80s. In the book I found some typed sheets stapled together dated 1964 that I had been given by Cosworth in 1984 when I designed my first piston for a Moto Guzzi. They refer to the SCA, a 1000 cc engine that had much in common with the Moto Guzzi V50 previously mentioned. Bore, stroke, valve sizes and the fact they both had Heron heads is what made me interested in the SCA at the time. I suppose the fact that I had a batch of pistons made for a big Guzzi and the SCA was twenty years old is what allowed me to get this information from Cosworth. Basically with the V50 Guzzi I had built half an SCA in V-Twin form.

 

The pistons for the big Guzzi were 88mm race pistons to my design and specifications but with a lot of help from the late Geoff Roper, head of the piston department. I remember driving up to Cosworth in my brand new red little Astra van with a Guzzi engine in the back. In Geoff's office we looked at the squish clearances and pin to deck heights and valve to piston clearances. These pistons were to go into my very first race engine. There are still some road bikes running around with these pistons in almost thirty years later.

 

After the first race I stripped the engine and was very concerned that there was no sign of carbon around the edges of the piston. I phoned Geoff at Cosworth to voice my concerns. He patiently explained that when the squish is working properly that is what happens.

 

Lots of water under the bridge since then. I went to visit Cosworth again in 2005. Big changes. The old guys with white lab coats and swarf on the office carpet have gone. A much sleeker operation with lots of young people with computers rather than drawing boards.

 

I looked up to the older generation of people like Geoff Roper. People who were there in the 60's when the DFV was born and a load of other exciting things were happening. Someone I know at Cosworth recently retired and was probably the last person still working there that knew Geoff.

 

When someone last week "discovers" a thing called squish my first reaction is to say "Listen, I was doing this thirty years ago". But then I remember Geoff and how patient he was with me when I was green behind the ears and full of questions. In fact the word squish and the name Geoff Roper will always be associated.

 

One day I will make a list of all the older guys that helped me. Not a long list, but some people were instrumental in teaching me some of the minsicule amount of things I know about four stroke engines. The subject is vast. I am always wary of the person that knows everything about engines. As far as I know he (or she) hasn't be born yet.

 

 

 

 

[Allen Payne]

Ammo - I think you need to stop building engines again and write a book instead.

 

I remember reading a book by Walter Hassan(?), who worked on Coventry climax & Jaguar V12 engines in the 50's & 60's, that was a great read - time for another one I think.

[Z3MCJez]

I agree with Allen. To me an engine is a one-piece unit (hell, it's even sealed with blue non-tamper tags!) that is bolted into the car and connected to the gearbox, electronics and cooling system. But I find these "ramblings" (said in a very positive way) fascinating. I just wish I understood more of what it meant! Squish, for instance!

 

Jez

[Martin J]

Suck...Squeeze....BANG....Blow....they all work on the same principle.

 

2 strokes excepted.

 

[AMMO]

Allen, I don't build engines anymore.

 

I support existing customers have had engines built by me, it would be wrong not to, and I will build race engines for those that want them and have no problems with my attitude on pricing.

 

Building run of the mill engines that everybody is also doing is not a good idea from a business point of view in my opinion. You have to compete on price. All the engine builders I know, and I know quite a few, are moaning that they want to get out. Some have already gone to the wall. Since I stopped building engines my turnover is way down but my profit is up! I'm not talking percentage, I'm talking actual money.

 

Engine building is time consuming. Hours of talks before getting the job (if you get it and if the customer doesn't go elsewhere with all the information you stupidly gave him), more hours than you actually bill for building the engine and then hours talking about it when you are trying to help out with the installation.

 

The race engine I built recently built was for a man who was determined that I should build it. I tried very hard to send him elsewhere but he was insistent as he races a car against someone else who has one of my engines. The guy is as good as gold, works in motorsport engineering at a pretty prestigious level, didn't want to know about cams, valve spring pressures or any of that stuff people seem to want to know. He didn't quibble about money, an issue that is very important to me! From my side of the bargain, the engine was delivered on time at the price agreed. I had told him it would make 280 bhp and 185 ft. lb. of torque and that's what it made. On top of which we are going to progress the project further.

 

I am only interested in development. I will upgrade my own customer engines and supply kits for people to build their own engines but the days of building the 210 to 260 bhp engines are over and have been for some time. Just not interested in them.

 

"Suck...Squeeze....BANG....Blow....they all work on the same principle." Pretty much. I find that it's how hard they suck and bang that makes the difference. 😬