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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 MGA - Lucas 25D Distributor Springs

All,
I posted this on the Twin Cam web site, but got little or no response.

UK Moss list the standard distributor MGA Spring set as 37H5272, but don't include it in their current price lists.

I believe this was been superseded by 57H5134, also no longer available.

Usefull reading on this subject.
http://www.jcna.com/library/tech/tech0015.html

As our cars are getting on for 50 years old and these springs would all be worn by now. Should these not be available to freshen up the advance curves back to what the factory had intended.

Does anyone have a stash of these anywhere or know where to get the correct one's

I'm particularly interested in the one's fitted to Twin Cam distributors which I believe are also the same as Copper S ones, as they give a longer advance curve but having said that even new standard one's would be preferable 50 year old one's



Thanks
<MARK>
Mark Hester

Mark
I had to get an exchange distributor for my 1600 back in 1998, as it came with the wrong one! A complete reconditioned unit was supplied by:

Holden Vintage & Classic, Linton Trading Est., Bromyard, Herefordshire, HR7 4QT

Everything including the springs looked like new, so they may also have twin cam springs...

Pete
Pete Tipping

Mark
Just checked, their website is www.holden.co.uk
Pete
Pete Tipping

From: chris@holden.co.uk

regret we are unable to supply springs for Distributors.

I guess springs are cheap and whole distributors make them money.
But I did find this.

http://www.custompistols.com/cars/articles/lucas25d4.htm

What is the Distributor number (s) for Standard MGA distributors ?

Thanks
<MARK>
Mark Hester

Mark. The MGA did not use a Lucas 25D distributor. Rather, it used the Lucas DM2 to specification 40510 most commonly.

The early MGBs used the Lucas 25D4 distributor to specification number 40897. It would seem that the 40897 is fairly close to the MGA specfication and would, probably, work without any problems.

Les
Les Bengtson

Mark,

I use a 25D in my Twin Cam with no issues. It has had the curve custom set though. That may be a way to go.
Paul Hanley

Paul,

Where did you get the Twin Cam Custom Curve settings from ?

I found the S/T curve settings here on page 36, but I'm sure the TC one's are different.
http://www.1978mgmidget.com/Special_Tuning_for_the_MGB.pdf

Thanks
<MARK>

Mark Hester

Mark,

The Twin Cam ignition advance curve is at:

http://www.angelfire.com/amiga/mga/Lucas/AEJ41_Ignition_Advance.jpg

The diagram is taken from the mga twin cam engineering Technical Data book, as used at the factory during production.

Mick
Mick Anderson

try aldon.co.uk
dominic clancy

I think you mean
http://www.aldonauto.co.uk

They seem to offer the following, but what advance curve they give is anyone's guess.

'B' SERIES APPLICATIONS
101BY1 A distributor with vacuum advance, designed to replace the original
distributor on std. MGB's and Marina TC's, fitted with HS4 SU Carburettors. N.B. Later versions of these cars have the vacuum advance pipe connected to the inlet manifold not the carburettor, use 101BY2 for these applications.

101BY1S Identical to the 101BY1 but fitted with a distributor cap which has the
H.T. leads coming out of the side instead of the top. Necessary for a few pre-rubber MGB's, where H.T.leads may foul on the steering column.

101BY2 A distributor with vacuum advance to suit std. MGB's and Marina TC's
when fitted with HIF4 SU carburettors. Improves driveability, while retaining the resistance to 'run-on'.

101BY2S Identical to the 101BY2 but fitted with a distributor cap which has the
H.T. leads coming out of the side instead of the top.

101BR1 A non-vacuum distributor to suit tuned 'B' series using camshafts such as 714,715, Piper 270,285 and fitted with a side draught carburettor.

101BR1S Identical to the 101BR1 but fitted with a distributor cap which has the H.T. leads coming out of the side instead of the top.

101BR2 A vacuum advance distributor to suit road tuned 'B' series, using 714, 864, Piper 270,285 camshafts but retaining the SU carburettors.



All good info, but I'm actually chasing a supply of the springs, as they bodies are the easy bit.

Thanks
<MARK>
Mark Hester

Mark,

I believe Les, above, has done extensive research on this matter and the conclusion was a big n/a on the springs. (I believe on the Twin Cam bbs, you got a link to cutompistols.com. Or perhaps it was his article in the last edition of MGB Driver magazine.) That's Les's take on the matter. Hope I'm not incorrectly representing your research, Les.

As far as the Twin Cam, it realy doesn't matter about original springs, it matters how the distributor operates through various rpms. That's why I took the curve, supplied by Mick Anderson, above, and dropped off the distriibutor to a shop and had it set to that curve. Now I know whatever the springs used, are correct for my particular engine. Don't want to overadvance the Twin Cam or Boom!!, you'll hole a piston. Car runs very well and in fact, this week I had it to yellow line for a few seconds in third!! Whoo hoo!

Paul
Paul Hanley

Paul. You are correct. The exact springs are not available. John Twist, at University Motors Ltd has an assortment of springs, a distributor test machine and the skill to produce an exact duplication of the factory curve.

I have contacted a custom spring maker and the various springs can be made up. But, the cost would be very high. If someone is interested in fronting the several hundreds of dollars necessary to have the various springs produced on a custom basis, I would be more than happy to provided them with what I have found. Or, if someone knows a small spring shop which will not charge $100 per set up to make custom springs, that might be of use. But, right now, I know of no one having the proper springs available as a replacement package. Maybe when the last kid gets out of college, I will have sufficient spare cash to have some springs made up? Les
Les Bengtson

Well looks like where making progress here.

How about approaching Moss UK or US to put in the initial cash. I know one of the Buyers here in UK quite well.

There seems to be many MGB spring sets, but only one for MGA's and one for Twin Cam's. Am I correct with this assumption. So Theoretically they could be re-released under the original part numbers.

I'm willing to put us some cash for some twin cam springs, if Moss don't come to the party any other takers ?

Last question, if new distributors are available, surly we can get the springs from that manufacturer.

Thanks
<MARK>
Mark Hester

Aldon did a complete rebuild on my distributor, and modified the advance curve for the Judson, so I am sure that if you tell them what springs you want, they can supply.
dominic clancy

Aldon, do indeed supply 25D distributor for many interesting applications, but it seems they are unwilling to share their secrets.

This is the reply I received.
********
Thank you for your email.

Sorry we are unable to supply distributor springs separately.

We could however recondition your distributor for you.
**********

So it's back to having them made ourselves to OEM Spec I feel.

Les has contacted me off list and will post some relevant MGA 24D4 data in his site soon.

Thanks
<MARK>

Mark Hester

The recon job Aldon does is fine work, and it's the same cost to recon and go electronic as buying a new dizzy.
dominic clancy

Update,

Still Chasing Moss UK to see if they will stock replacement springs for MGA's 23D4 Distributor.

However this distributor is on offer at.
http://www.123ignition.nl
http://www.123ignition.nl/pdf/123MG.pdf
http://www.123ignition.nl/pdf/123MINI.pdf

It offers 16 settings, so Ideal for fine tuning or Dyno tuning and would probably be more accurate than our 50 year old originals by now.

As Aldon don't show any pictures and offer a huge range, I wonder if they are not offering the about?

Anyone tried one ?

Thanks
<MARK>
Mark Hester

This thread was discussed between 16/05/2005 and 31/05/2005

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