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MG MGB GT V8 Factory Originals Technical - Oselli 1995cc info
|I have a 1995cc Oselli lump in my GT with a melted piston. Oselli tell me they are made of "unobtainium" so the big Q is - which pistons did they use. a Google search has come up with various piston makers (v. expensive for one-offs) but what I need is a catalogue or database of pistons used in other engines (bores are 84.25mm but calculation says 84.5 to give 1995cc) or even better Oselli pistons from a broken engine.|
|Are there any identification marks anywhere on the Oselli pistons?|
I think you will find that the 2 litre "O" series engine from the MG Maestro or Monetgo of the mid 80s to early 90s had 84.5 mm pistons - could Oselli have used these?
Peter Burgess builds 1950 cc B series engines - have you spoken to him?
If you have to have to go along the remanufacturing route I would advise a full set of pistons rather than a singleton.
Accralite will make forged pistons, and they are not too expensive:-
|We used to use Lotus Cortina pistons when building 2ltr. B-series engines. If your pistons have valve reliefs on the left and right sides as one would expect to see in a dual overhead cam hemi head engine, then you have the Lotus Cortona pistons.|
|Thanx for that guys, BUT have already explored the Lotus t/c route, that's not what they are. Lots of people do 1950cc engines (actually 1947 or 1948) using 83.5mm pistons, so mine could be oversizes of those. |
Will have to look at "O" series pistons. Neil Cairns also said that Abingdon made experimental 2l. engines before the "O" series.
Have sent a query to Accralite, so am holding my breath!
|I expect you are looking for four ?|
I am not an engine expert but when I last spoke to Oselli about an engine build the 1995cc was the same bore as the 1950cc. The extra capacity is gained by offsetting the crank/bearing and giving you an increased stroke.
Why don't you just ask Oselli what pistons they used and where you can get them?
|Give Chris Betson of Octarine Services a call. I'd use him over Oselli any day of the week.|
This thread was discussed between 19/02/2006 and 22/02/2006
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