MG Car Club of South Australia
MGC NEWS MGC conversations by Richard Mixture,
H
March 2018 More advance less speed
ello, it’ s Richard here again. That nice young Register Co-ordinator showed me a letter he’ d received from one of the MGC owners in our Club. Putting it bluntly he wanted more speed. There can’ t be too many MG owners who haven’ t said that at least once over the years. Anyway, Lynton and his‘ C’ toddled off to Specialty Tuning, a business that evidently specialise in“ distributor graphing and carburettor overhaul”. While I’ m not sure what graphing a distributor is, anyone who can overhaul a carbie these days must be worth a look.
So this is what Lynton’ s letter says;
“ Thought I would share with you my recent‘ C’ experience.
Although smooth and easy to drive around the city the engine has always felt like it was running out of puff above 3500rpm. Towards the end of last year I took my friend in my‘ C’ on a high speed hilly run on a warmish day. I was concerned to notice the engine pinging( detonating) above 3500rpm uphill with more than 1 / 2 throttle.
I consulted Neville Smith at Specialty Tuning, Marion. He advised that, although he had not worked on a‘ C’ before, he had extensive experience with Lucas distributors and believed the distributor may be over advancing.
Neville took base line figures on chassis dyno as a starting point. He removed and bench tested the distributor and found a total centrifugal advance of 65 °( 28 ° is standard). The distributor had been modified( butchered) to give the extra advance. Neville commented he had seen this modification before with Lucas distributors and someone local is mistakenly butchering them thinking they are doing the right thing. He reversed the mod and replaced the centrifugal springs to correct the advance curve. Finally he chemically cleaned the induction system to remove built up gum and carbon.
The final dyno reading showed a 10 % increase in total power but more importantly the engine now pulls easily to the red line with smooth and constant power.
I would recommend Specialty Tuning to anyone who is looking to get the best out of their MG.”
Well done Lynton, a bit less advance provides a bit more speed. I recall attending to this problem back in 2008 along with several other Register members and wrote about it in the November Club Magazine that year. We fitted electronic ignitions and had our distributors overhauled and found a wonderful improvement in performance.
Lynton goes on to say;
“ I too have fitted electronic ignition. It was one of the first things I did. Purchased from eBay and fitted in situ with static timing reset. It made a big difference.
I did not know the dissy had been butchered until Neville bench tested it. All I knew was there was something not quite right. The pinging and running out of puff above 3500rpm being the main issues.
He quoted for a full tune including
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