Lagonda Rapiers

8 minute(s) of a 484 minute read

Happy Easter.
I have decided to go back to where I was in January, using the opriginal "Barker" manifolds but with the balance pipe I made then but did not use. All the experts suggested that it would not work with the balance pipe on the underside of the inlet tract, it would fill up with unburnt fuel.  I will wait and see before commenting further.

I am now waiting for the super strong epoxy that is to hold the balance pipe in place to sets. On the exhaust side; of course the middle of the Easter holidays is the ideal time to run out of gas, no not petrol, but oxygen and acetylene. I have just replaced the old (leaking hoses). I probably have about a days work to finish the hard part of the exhaust. I will then have to make some decisions whether to replace the muffler and tail pipe or just the tail pipe. There is really nothing wrong with the muffler except age and I am very much against getting rid of things (or people) just because they are becomming old.

 It (the muffler) is a very eficient design and works very well, it is quiet, but does not create any excessive back pressure being a "straight through" type.

For all the experts on "tuned length" exhaust systems and followers of "Phillip H Snith", I know that  none the four primary pipes are exactly the same length to the last millimetre. I have increased the size of the secondary pipes to 1 3/4 inch diameter and fitting them all in while leaving at least half an inch clearance all around was quite a task! I can still take them off and put them back on again without having to remove any body parts, mudguards (fenders) etc which in my book is a major achievement. I still have quite a bit of welding to do and to tailor the "collector" for the end of the secondary pipes where the exhaust will go into the one, two inch diameter, pipe leading to the muffler.

This is a basic 4-2-1 system which I consider (among other people) to be the best arrangement for all round use. It gives a good spread of power over the entire rev range.

4-1 systems may give slightly more power at peak revs but how often do you drive a "road" car flat out?

I have just cut up a 4-1 system which has hung un-used on the wall for years. I wanted to use the steel  base plate.

Bj.

The space below is for all the people who would like to tell us all about their favourite exhaust system/s........ Yes  even MG owners, Here is your chance.....

4-17-2017

Back to square one, the original "Barker" inlet manifolds now fitted with a larger "Balance pipe" finally installed on the cylinder head, one more positive step towards having the Lagonda back together again and running.

Bj.

4-18-2017

Oh Dear! I must be getting old! I have spend the afternoon welding the exhaust headers together, sounds  easy doesn't it? Just for six lengths of pipe, a steel plate with four big holes and eight little ones and two or three joining pieces. Having made a couple of false starts I decided that the time had come, I have replenished my two gas bottles and bought a couple of tubes of welding rod.

Some four hours later it is about 90% done. Possibly the tricky bit was making the headers so they went on and came off almost as easily, as I had explained earlier.

I can tell you now:- It ain't all that easy, another hour or three and it will be done.

It is now time to turn off the gas for today and get cleaned up ready to pour the cook that all important"Pre-dinner Drink"...... Cheers!

4-19-2017

With the exhaust headers all but finished I have turned my attention to fitting the carburettors. I am now waiting on some gaskets. With the headers in place I can then refit the muffler and tail pipe.

Once again I have run into strife with the inlet side, it is virtually impossible to mount the carbs onto the manifold with the dreaded balance tube in place. I have now removed this yet again and will investigate fitting screw-in plugs into the holes. This will involve cleaning up the holes and tapping a thread into them before making the screw-in plugs. I may be being over cautious but I cannot bring myself to trust the epoxy "stuff" to be a permanent fix. All it would need is for this to crack or partially fall out to weaken the mixture and cause havoc. I really cannot afford another major engine rebuild. Neither the cost in Dollars or the  mental and physical strain.

Bj.

4-22-2017

Finally I have the Rapier all back together but I am having a small problem sorting out the static ignition timing with the electronic ignition. It may be something I am doing but to my simple mind it would appear that the timing of the  point of spark is not properly synchronised with the rotor and the distributor cap. Using a timing light it would appear that it is timed to "spark" when the rotor arm is halfway between two pick-up contacts. If any of that makes sense. One thing is sure it does not want to start!  I am tempted to pull it all out and put the points set back in. I am becoming very expert in throwing money into the bin....... I will wait until Monday when I can talk with the experts who supplied and fitted the Electronic set-up.

Apart from that and one or two small oil leaks it is looking good. I actually gave it a wash last thing this afternoon. It looks a whole lot better all in one piece and with all the grubby hand prints etc washed off.

Thank you Paul

It is one that I would sooner not have but I will keep you informed. The good news is that finally The missing parcel that was coming EXPRESS AIRMAIL from the UK has finally arrived. It was posted on 10/03/17 so I guess that the Express Aeroplane that was bring it ran out of steam or the Pilot got tired of pedalling.

5-2-2017

I know that most of you have already seen photographs of the Rapier engine before but for anyone who is interested here are todays photographs of the engine now that it all together and starting on the button and running nicely, idling smoothly at 800 rpm and 40 psi oil pressure.

So what is so special about the one "odd" cam cover nut? It is the last surviving example of Beatrice Shilling's dedication to weight saving. Purpose made at the Royal Aircraft Establishment at Farnborough (England) in the early 1950s it is Duralumin. 

Bj

Hello Paul

Thank you, yes in the end I decided that was the best option, as Helen (my wife) commented; we have done over 100,000 miles using the same inlets. To use the "new" manifold would have entailed either making some significant alterations to the bonnet (hood) side or leaving it off. All this means that I now have a brand new inlet manifold sitting on a shelf that (cost over $200) I will not be using.  To make a new bonnet side, or to make the necessary changes to the original to accommodate the carbs using the new manifold would cost nearer to $1,000.