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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - forged or cast

Just starting on a rebuild of my spare 1275 lump. The existing is using forged pistons C-AJJ 3377 which I managed to find in sale years ago. They have a 6cc dish. Is it worth using forged again or are cast sufficient?
Bob Beaumont

I've used cast pistons in race engines without problem, but they weren't made from chinese chocolate!
Dave O'Neill2

Thanks, I know Omega are ok but pricey: £300 for cast and £480 for forged, any other 'safe' manufacturers?
Bob Beaumont

From vizard IIRC

Cast for street engines and forged for racing engines...whay that is ..I dont recall
Prop and the Blackhole Midget

I'm using MiniSpares P21253-60 in my 1275's current incarnation. They're decent cast pistons and very inexpensive. I figure they'll be fine for an infrequently stressed road engine, but I'll be sure to let you know if they asplode.
Growler

Prop, "why that is ..I don't recall" stress and loading. Race engines work harder, faster and (usually) at higher compression pressures, hence the need for stronger pistons. Road cars in mild to fast spec should be fine with cast unless you are going the whack up the CR and thrash it everywhere.

MGmike
M McAndrew

Bob:

Forgive me for being off-topic, but I thought the adjective "lump", at least around these parts, was strictly reserved for the the Triumph 4-pot of later vintage. Being a 4-pot owner myself I am pleased to see the slur diluted in such a profound and inclusive fashion. Thank you.

I had always assumed "lump" was intended to separate us 1500 wanna-be midget owners from the true calling, so as a derogatory slur, pray tell why would you use it for the later incarnation of the a-series engine, or any other engine for that matter?

I realize the facetious tone of my query, but actually I am quite serious.

As far as the pistons go, this shade tree mechanic wouldn't have a clue.

Richard
Richard Reeves

Richard

My reference to 'lump' really related to any engine. It was coined by my late father, a motor dealer, who used the adjective to describe generally the condition of the engine. for example 'its got a good lump in that' or 'it needs a new lump before sale'. Its a commonly used expression particularly in South London!

Its interesting that 'over the pond' its used to differentiate the two types of engine used in Spridgets. I am glad my reference is more inclusive!

Bob
Bob Beaumont

Thats right Bob. For us old UK types Rich a lump over here is generally of iron but could be of any material that works, any type wether its a good one or not. Synonymouse with 'shed' as in - its a bit of a shed - means its a bit like a van (won't sell well, is capacious, doesn't go around corners, etc.) not at all like any midget. Its a general term used across the motoring heards not to differentiate them.

Therefore Bob's 'iron' is not a lump (even though its iron) cos a lump is an engine.

Wot english? You should try some British local coloquialisms. I darn't start using my black country sayings from when I was a lad. (remember the black country made the parts, the motor manufacturers just put it together - ha ha ). Its just like some of the local dialects in the US of A are impossible for us.
Dave Squire - Notts

Ho'way man, ah divint nar wot ya on aboot. English is English aw ower a world an a lumps a lump in any lingo.
see the link for the reet meaning
https://wads.le.ac.uk/ee/Slangsearch/Home.aspx?WebSite=geordieslang

Derogatory term for a person (thing), meaning useless.

an' that's a 1500 motor reet? Not bonny like me 1275!

sorry just couldn't resit....

MGmike
aka. Georgie Mike in the land of Haggis and Neeps. Oh how my English is screwed....
M McAndrew

See what I mean?

I think its great, I love regional and individual variety. :)
Dave Squire - Notts

Is it me or is mike the only one on here speaking properly?

English by birth, Geordie by the grace of god.


Paul
Paul Barnes

I thought forged pistons expaneded more and so had greater clearance when cold. This made them rattlier and possibly even even smokier when not up to temp. A reason not to put forged in a road car. Although I could be totally wrong but I remembered being told this when a friend new race car engine was rattley.
Greg H

This thread was discussed between 18/09/2012 and 21/09/2012

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.