1959 MGA Twin Cam Coupe - Full Restoration

Read about my project's background here: Start of a Twin Cam Project...

Things get more interesting as we turn to look at the cylinder head. Boy, isn't it a work of art that shows "what could have been" for MG. It certainly doesn't have the beauty of the similarly sized Alfa Romeo engines, or the elegance of a 6-cyl Jag, or the power of a Ferrari or other V8/V12 beast... but that's part of what makes it special. It looks smaller, more functional, more spartan - very appropriate for the MG badge. I digress...

The cylinder head looks at first to be in pretty good shape. It had been partially disassembled by a previous owner, with the cams and exhaust valves removed. It was filthy but cleaned up pretty nicely, good think aluminum doesn't rust...

The deck seems flat and the combustion chambers are well shaped without pockmarks or excessive buildup. The exhaust valves had been previously removed and with the exception of one bent valve they look "ok". I'll replace them as a set. I removed the intake valves without incident using a valve compressor tool from Amazon (the type with a C-shaped clamp) and they look great - might as well reuse those too.

The cam bearing caps seem to be in good shape and the bearings themselves seem alright. A new set of bearings isn't very expensive so I'm leaning towards replacing them anyway.

Now for the bad stuff:

Broken Tappets are evident on the Cylinder 1 and 2 exhaust. YUCK. I wish I knew the history of this car, and how these were found. I guess they were probably driven for some period of time with the broken tappets, because I don't know how else you'd get two of them to break at the same time. I can't remove these from the sleeves, so I'll need to ask the machine shop to help. I have a set of 7 tappets that came with the engine, with one of them not having a chamfer. More mysteries - why are there 7 when 2 have obviously broken in the car? I'll probably do a better inspection of what I have and reuse any that seem ok.

Tappet Sleeves seem ok, aside from the two with broken tappets. I spoke with Jim Alcorn and he recommends replacing with bronze sleeves (pressed into the head and finished by the machine shop). I'll probably go this direction, since I think I need to replace two of them and don't want to mismatch new bronze with old parts (anyone know what they're made of??).

The Intake Ports show another surprise - looks like they were welded up where the valve guides are pressed, and have cracked over time. Not happy about this. Will chat with machine shop about whether they think they can repair this... don't really know how big of a deal it is yet.

Camshafts are a rusty mess and certainly show signs of wear. I'm guessing the previous owner did a poor job of maintaining valve clearances as some of the cam lobes are pitted/chipped. The alignment shoulder/fin on the "front" of one of the shafts is broken, which doesn't necessarily seem like a dealbreaker but probably worth fixing anyway. I scrubbed the camshafts down with some penetrating oil ato remove the iron oxide, which exposed the rotted base metal underneath. Why on earth would you let this rust like this?!? I'm planning on sending these to Delta Cams to have them make them pretty... fingers crossed they'll take the job.

Next step is taking the head to the machine shop to see what they think.