MGA Ignition Timing

[VWNate1]

My MGA 1500 engine has an 8.0 : 1 compression ratio and is lightly ported & smoothed up to flow well .

It starts easily cold ot hot , never has a miss nor stumble , doesn't ping , knock nor diesel no matter how hard I run it .

Question : I'm currently running 20° BTDC initial timing , can I bump this up to 15° ? .

TIA <

[malcolmr18zoy]

Hi Nate,
You're currently at 20 degrees BTDC and you want to bump it up to 15 degrees BTDC? That doesn't make a lot of sense to me. I can say that I think your car sounds retarded, and I would certainly try advancing it By ear, and see what happens. If it never pings, It can probably stand some more advance. Are you using premium gas? Oh, and you have a 1600 cylinder head, which has larger combustion chambers, so your compression may be less than you think.
Malcolm

[Steve Simmons]

Advance the timing and run it hard in 3rd gear throughout the range. It it doesn't ping or lose power compared to before then stick with it or try for more! That's how I time most of my cars. Timing lights are for wimps.

My butt dyno is better than any flashing light bulb anyway.

[VWNate1]

Agreed but ;

A. , it's a slushbox and

B. I don't know if I can still hear pings under load.... typical Journeyman Mechanic ,my hearing is shot .

[VWNate1]

FWIW ;

Victoria British has the Pertronix Ignitor on sale for $89 this minth , also the correct screw termnal vltage regulators for $35 (install your original LUCAS cover to look nice) , brandy new Lucas generators $ 90 etc. ~ I've been running one of these new generators in daily service for about 10 years now (was $150 when first available) and so will prolly just bin it when it eventually craps out .

Loads of electrical parts on deep discount this month only ! equals fee shiping and taxes .

I hope to get my new Ignitor installed to - day as Sat. next , we're off on a two day Auto Tour and my little Metropolitan Nash FHC needs all the help it can get .

I look back over my original post and I meant : I was running 10 degress lead avance , not 20 , I have fat fingers to match my head .

[VWNate1]

YEE~HAW [b![/b]

I installed the new Pertronix ' Ignitor ' and checked the spark plugs , gapped them out to .045" and boy howdy does it run sweet ! .

I set the timing to 18 Degrees BTDC @ idle , we'll see how it likes that , I have a two day Road Rally next weekend so I fixed the oil filter O-Ring & crush washer leaks too .

I sure love how a well tuned BMC 'B' series engine purrs .