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MG MGB Technical - MGB 18V engine refresh

I recently bought a 72-73 GT and while I am normally more into midgets (ooh err, missus!) I now have another B after 30years without.
I ended up building a 1950 breathed on engine for my last B but this was the last engine I built and have lost a fair amount of knowledge over the years. The prices of parts, compared to then, seems astronimical as well.
I need to drag the gearbox out soon to swop it over as its a bit noisy, when I do I was going to look over the engine and refresh it, reboring and refresshing the bearing shells as well as generally sorting it out while out the car.
Was considering a 1950 but not all the trick bits as I am looking for driveability rather than performance. Better torque and mid range for daily use would be what I am looking for.
Any thoughts or opinions on the cost affectiveness of this or any alternatives that would keep the engine basically standard but give a bit more oomph?
Neckieman

I'm planning to keep my engine fairly standard, but, like you, I would like a bit more torque.

With that in mind, I shall be fitting one of Peter Burgess's Econotune cylinder heads and possibly a mild tune camshaft.
Dave O'Neill 2

More power and torque? Don't go wild on camshafts, the standard one is very good. Get the gas flowing better and add a bit to the capacity. 60 thou over-bore, flowed head with 3 angle valve seats, decent exhaust, better induction through K & N's. Balancing makes it smoother and rev better.
Allan Reeling

Don't really want to go for external bits like filters, exhaust and suchlike.
Was thinking of a mild cam, maybe, an overbore to +60 or 1950 and possibly putting K@N's in the original filter boxes.
Not looking for a racer, just a bit more usable power and torque for normal road use.
If I want to go really fast I can get out the 1000cc bike and do 0-60 in about 3-4 secs...........
The GT is for touring and going to work every day.........
Neckieman

Send the head out to Peter Burgess for porting and polishing. The B head is very restrictive in its stock form and getting it opened up can make a world of difference in obtaining more power from the engine. RAY
rjm RAY

Porting (polishing is a misnomer) is all about efficient mixture and exhaust movement. Unless you remove restrictions "outside" the head you are reducing the benefits of the head work. Why you wouldn't do this I don't know. If it's an appearance thing, the cast manifold isn't too bad, but do bolt on a less restrictive system.
If you are having the head, at least mildly worked by Peter, get him to skim the head to raise the compression ratio, that and the +0.060" bore will improve the flexibility and torque of the unit.
Allan Reeling

Simply adding .060" oversize pistons, a Kent 285 camshaft kit and polishing and port matching the intake and exhaust manifolds made a very noticeable difference in the performance of my otherwise stock engine.I did have a small amount of material removed from the head, to increase the compression ratio to around 9 to 1, but opening up the Siamese ports, on the head, allows it to breathe a lot more efficiently. Essentially, free horsepower. RAY
rjm RAY

This thread was discussed between 21/03/2016 and 22/03/2016

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