chrisss wrote on Mon, 01 September 2003 20:16

space on either side of a 1uz - what could that be for????

not even close

not even in the ballpark
hell, not even the same game

franky - you keep your trap shut!

and to clarify, i meant "how much space is there on the side of the 1uz between the block and the fender wall" just to get a feel for how tight space is within the bay at the sides ....



cheers
ed

[Updated on: Mon, 01 September 2003 14:23]

note to self...

(beats emailing myself repeatedly )




ALSO

http://www.pumaracing.co.uk/
http://www.pumaracing.co.uk/pp02.htm
http://www.pumaracing.co.uk/cflow.htm
http://www2.gol.com/users/tube/essex.html
http://www.classicjaguar.com/leeder.html

V12
43.5mm Inlet. Uses throated standard seat
36mm Exhaust. Uses throated standard seat

Dear Mr Lambertini,
I have two questions for you. I would like to know why you decided to adopt the Heron chamber in designing the Morini modular engine.
I don't remember similar solutions in motorcycling (maybe the Lotus F1 in the 60's?); the design of the head is much more simple in this way, but the piston is complex and heavy.

I would also like to have more information about the 500 Turbo.
I was a student in Engineering at the time and I was lucky enough, thanks to a friend of mine who was a Morini dealer, to visit the R&D section of the factory in Via Bergami, Bologna. Here technicians were preparing a dirt bike for the Paris-Dakar rally, but I was attracted by the Turbo: it was there, disassembled (but it was possible to see an impressive heat protection under the saddle) and without its beautiful fairing.
I could also talk to a tester. He told me that the bike was very fast, but difficult to manage on the wet, because of the turbo output.
I would probably have bought that bike and so I was very interested.
Could you please briefly explain what the real problems of that prototype were?

Thank you and best regards
Piero Ligorio

ANSWER

Heron combustion chamber.
This is what the management of Moto Morini asked in developing a new engine: "Engine multiple use, to be mounted on different types of vehicles, with a capacity from 125 cc to 250 cc at first, then 350 cc and finally 500 cc; better performance than the rivals, giving more importance to torque and lowest consumption; simple and compact design, at the same time giving an impression of strength; maximum application of the principle: 'what is not there cannot be broken and does not cost anything'; limited production cost; easy industrialisation, as to best reduce investments".
It was of course not easy to develop such a project, putting together such contrasting principles.
In this situation it was immediately clear that the best shape for the combustion chamber was the Heron one.
The design of the combustion chamber had valves put perpendicular to the head plane: this allowed low investment costs for operating machines and low production cost, as the different phases to complete the head were faster. Operating or transfer machines we were going to use were dedicated to the specific project, not at all flexible. Today we would use digital control machines: another world!

The position of the valves was misaligned in respect of the centerline of the cylinder, so that we could put the plug near the centre of the head, making the combustion easier.
The turbulence of the charging was increased by the wide rolling sections on the piston and the "heart" shape of the chamber conveyed a great part of the fresh oil mixture near the plug, thus making the spark and spark advance of the front of the flame easier.

This type of combustion chamber, combined with a specific design of the piston hollow, bear high compression ratios (10,8-12:1, while the other engines of the same time had 9,5-10,8:1).
On the other hand the combustion was a bit harsh, the piston was heavier, thus making it more difficult to eliminate vibrations, the top of the piston had a higher temperature, so that the working clearance between barrel and cold piston was increased and the engine became noisier.

[Updated on: Wed, 03 September 2003 01:27]

[Updated on: Wed, 03 September 2003 00:41]

the BMW v12 is even more low tech (unless youre talking about the late 90's quad cam 6L?)...

if you have a point dave, please feel free to make it



cheers
ed

[Updated on: Wed, 03 September 2003 01:12]

franky,

i guess 'relatively' should be thrown in there. what year did the bmw v12 design originate? i dont know myself. i suspect it was much later than the jag model, and 'relatively' speaking, should be significantly more advanced in design - but it isnt.

i dont have enough specs in my head to answer your question confidently. simply because ive been more focussed on the 60's head design that comparing the bmw numbers. that said, from preliminary reading, there is nothig at all that excites me in the bmw design. it was a cheap build, with a very budget route taken to head and intake design. its still a sohc, theres nothing flash in the comb chamb design, the compression is lower. theres probably up sides to the motor as well, but as i mentioned, i havent done the reading. i dont even know what the bore stroke is (would be doing well to elbow out 90x70mm).

i also highly doubt that the bmw v12 grows on trees, and is available in the junk yards (and peoples backyards when wrecking their rusted shitboxes)...

that said, sing me their praises....

the jag v12 has a LOT of hitory and heritage behind it which makes it an attractive piece to reserach, and discover the deign developments. engineering of the post war period has always interested me, and this is one way i can actually get into it a little more comprhensively

granted, this might not lead to a brilliant highly efficient powerhouse (by todays standrds) but thats not really the goal i have in mind

cheers
ed

[Updated on: Wed, 03 September 2003 01:46]

agreed, the jag comb chamber is shithouse

but, if you start reading the design briefs of the day, and take into acount the complexity of machining equipment at the time (late 60's) its really interesting to see how the engineers came up with novel solutions. gotta give em credit.

and the soundtrack will be funking unreal.....

PLUS

it cant be terribly uterly crap if the 80-90's lemans 'silk cut' jaguar ran this exact engine, and walked away with plently of shiny medals...

TWR engine
8000rpm redline (factory standard)
+700hp and 550NM



cheers
ed

[Updated on: Wed, 03 September 2003 02:00]