MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

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 MGA - MGA distributor info needed

I have a rare Riley car that has the 1588cc MGA engine fitted. It was modified by the BMC agent in 1961 prior to being sold new.

It has a Farina body and began life as a Riley 4/68 before being modified and sold as a 'Riviera'.

Can someone please advise me which distributor (and the part number) would be fitted to this engine originally?

The engine is not a twin cam one and looks to be a high compression one as it has the flat top pistons.
Any help appreciated.

Mick Holehouse
Colne, Lancashire, UK
Mick Holehouse

The distributor type is Lucas DM2.P4 original part number is 1H811.
Neil McGurk

Mick
So you've got the MGA's "1600" engine. Neil is right with the numbers. An exchange unit is 1H11E and was a Lucas 40510.
With flat top pistons its just possible you have a high compression 1600 MkII engine at 1622cc which is a 12H822E as an exchange unit - Lucas 40780.
For recon I found "Holden Vintage & Classic" do a great job (www.holden.co.uk)
Good luck
Pete
Pete Tipping

Mick,

Just to clarify, the 40.... numbers are stamped on the flat face of the distributor body, along with "DM2" and the date of production. If your unit has a different number it is from another car. It was not unusual to swap DM2s around in the mistaken belief that they were all the same, but the numbers distinguish the internal parts like bob-weights and cam, which are the source of the advance curve.

Of course the original curve was for 1950s petrol but the modern stuff will take more advance. That's a whole different issue best dealt with by a rolling road!

Cheers

malcolm
Malcolm Eades

Thanks everyone for your help. I have never been able to get this car to perform as well as it should. The mystery is hopefully now solved as I have had a Farina distributor in it which is the 25D. I have found the correct DM2 one needed in some spares I got with the car. I will now get it re conditioned and it will hopefully run much better.

It is the 1588cc engine fitted as well as Healey disc brakes and wire wheels.
Mick Holehouse

Mick
I thought mine was a 1588cc engine, till I did a rebuild and found it to be fitted with oversize 1622cc pistons and "1622" con rods on the wrong cranks (think about it) with an early MGB head and the wrong distributor. Trouble was it had the original type of dished-top pistons which meant a very low compression ratio with the B head. This was restored with the flat top type with the rods on the right pistons... Just shows how they can get mixed up. Goes like a rocket now!
Pete
Pete Tipping

Pete, I have similar engine modifications as you do, which is a 1588 bored out to 1622 + 30 thou (1650) and I'm using the origianl DM2 distributor. I also have a brand new Lucas 25D4 40780 (which is not a DM2) which you say is the correct replacement for the 1622 engine. Is this the dizzy that you are running on your car? My car runs great but it seems to run out of accelaration too soon, so perhaps installing the 40780 will help.

Thanks

Andy
60 Coupe
Andy Preston

Thanks everyone. I have ordered a new one from MGOC Spares so hopefully it will run much better now.

Pete I actually found the car in Hampshire and it was a Hampshire car most of it's life. (Basingstoke & Andover) but it is now up in Lancs (not IOW as my registration says).It was originally a Riley 4/68 and Wessex Motors of Salisbury converted it to a Riley Riviera prior to sale, new. Wire wheels, cut down tail fins Healey disc brakes, MGA 1588cc engine and a number of other mods were done using BMC parts.

Mick
Mick Holehouse

Mick, Good luck with the dizzy. You lost me talking "Riley" though!

Andy, Yes I'm still using the 40510 which is correct for 1489 & 1588cc, as at the time, that is what I thought I had. I don't think I have any problem with it as on the 99 octane Shell V-Power fuel we can get here it will rocket up to 100mph. At +0.06" mine's up to 1685cc!

On checking I see the 40780 is actually correct for the 1600 MkII. So there shouldn't be an issue for you.
I assume you have checked all the usual carbie, fuel pump and ignition things that slow us up. You can always put the old one back if you don't like it!!!

Helping an MGA mate recently I found a lump of rubber partially blocking a float needle valve and then there is the 'over-winter' dried out fuel deposits that can bung up the hole between the float chambers and jets.
Pete
Pete Tipping


Its a great car Mick and will be such a one off when its restored - I remember seeing the pictures of it. Perhaps you can give a little update / photos on the farina page - it could do with a kick

Some great stuff here on the MGA pages - I am a frequent visitor from the Magnette page as we share so many parts and problems.

Just rebuilding my H4's and amazed at how much crap there is in all the nooks and crannies.

Regards
Gobby
ZA & Mk4
Gobby

This thread was discussed between 30/03/2010 and 13/04/2010

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.