Toymods Car Club Inc: Tech & Conversions => size limits in the MA70 engine bay... (pete?)

Toymods Car Club
www.toymods.org.au

F.A.Q.

Home

Members

Toymods » Tech & Conversions » size limits in the MA70 engine bay... (pete?) Show: Today's Posts :: Show Polls Email to friend

Author

Topic

ed_ma61
Forums Junkie

Location:
Lost in the K hole
Registered:
May 2002

Re: size limits in the MA70 engine bay... (pete?)	Tue, 02 September 2003 06:51

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] [Report message to a moderator]

[Message index]

-=] Back to Top [=-

Current Time: Tue Jul 29 04:01:28 UTC 2025

Total time taken to generate the page: 0.0060420036315918 seconds

.:: Contact :: Home ::.