MG Sports Cars

Morning all

I’m in the UK, new to the forum., and hoping the wealth of knowledge here will help steer me down the right path.

I have a 79 GT that’s being converted to V8 and chrome bumper.

This weekend I’ve stripped down the engine which was an eBay purchase a while back. Here’s what I know;

Engine number starts 10A, which I believe means it’s from a manual SD1. Compression ratio is 9.35:1. I have a JWR Offy dual port manifold and Edelbrock 1404 500cfm ready to go. Gearbox is 5-speed LT77.

The engine had been stripped and ‘partially rebuilt’ by the previous owner. However I’ve stripped it back to a bare block to start again - partly because I’m not taking any chances on someone else’s work, but also because he’d done something wrong as the engine wouldn’t turn over even with a socket and bar on the pulley. As I dismantled I expected to find a seized piston or stuck valve, but all were fine. I suspect he’d used old mismatched bearing shells tightened incorrectly and with no assembly compound, so it had all pinched down tight. Hopefully that’s all it was(?)

Two questions have come up so far;

Valves - I seem to have a bit of a mismatch. Inlets are all 614088 VL, except for one which is a 614088 B.C. and looks slightly different. Exhaust are all 614089, but one has a V after it and the others don’t. I don’t know what the V/VL/B.C suffixes mean.
The exhaust valves are fairly pitted after a clean up, and one is really bad. That, combined with the apparent assortment of types is steering me towards replacing the whole lot (inlet and exhaust). Does that sound sensible?

Camshaft - on removal I’ve found it stamped BP285, which I believe makes it a Piper ‘Ultimate Road’. After initial excitement at this discovery (the inner kid!) it’s occurred this needs some careful consideration. A lively Cam might be great for enthusiastic drives, but I wonder if the idle will be annoyingly lumpy and the drive not so good if cruising around normally. Also, more importantly, the heads have standard single valve springs, and I’ve read conflicting opinions about whether that Cam can be run without upgrading to double springs and machining the head to suit?

Has anyone got experience of a similar set up to the above? Any thoughts and guidance would be very welcome.

I’m not aiming for a racing machine here, but if I can get the old girl to nudge over the 200bhp mark that would be great.

Many thanks