What kind of spark plug heat ranges and designs are people using for worked A15's with 10:1 compression.
I am trying to find the right one but I am using at the moment NGK BP5ES. The B5ES seemed to work better I think.The difference being that the electrode sat
almost below the thread.

Another thing, are any of you finding that the lead replace petrol is crap.
I try to use Optimax every so often and the car runs a hell of a lot better.
OH well, they are all just bad carsenogenics.

yeah there was healthy debate on this a while ago (about the fuel anyway) and the general consensus was that LRP actually harms the engine over time. I have since talked to
mechanics about it and they agree.
Keep using the Optimax. with the better fuel efficiency, it doesnt cost much more, if any.
Linc.

i just used genuine plugs with my A15 and the ywere magic.

as for the LRP fuel, if your running an A15 head then you can run premium unleaded til the cows come home. optimax will actually be better for your
engine than super is.

run straight on premium all the time. i did with mine and never had troubles.

Justin

With that sort of compression on decent octane fuel you should be using something like a BP6E or even a BP7E. I would imagine that you are running about 10-12degress of initial advance.
Has the distributor had the ignition curve changed ???. Some Datsun distributors have heaps of advance in the distributor(mainly A14&A15) which isn't a good thing for modified motors.
The units out of the A12's tend to have less, allowing you to run more initial.
Basically giving better performance.

James