spark plugs and valves - 07/13/22 03:54 AM
so my questions today would be pertaining to valve lash and spark plug gap for my 1925 coupe
Spark Plugs - Champion W89D
i set my gap to .030 as per my manual
i kept seeing people online talk about .040 spark plug gap so decided to try it and it definitely increases my pep in the car and has a ton more power to it and seems to run a little bit smoother (original coil)
now the question being why would i get so much better performance despite the manual stating a lower amount?
and should i keep increasing it until i get a miss or less performance? or is that ill advised?
also
i have 2 other sets of plugs wondering if they may be a better fit. most of the talk for the spark plugs seem to be for 28's and mention the 3077's which are no longer made
should i try gapping these to .040 or would it be futile
Autolite 3076 set at .030 they would run okay but lack of power and occasionally missing.
Autolite T7 set at .030 as well. they caused misses / backfires at high speed. i cant seem to find almost any info on these plugs but they came with the car.
i have a roughly 1-3 mile loop with hills nearby that i do to test the car when adjustments are made depending on which turn off i take, can be long or short.
as for the valves for a 25 with a 25 head single port exhaust my manual states set the valves at .010 exhaust and .008 intake when hot yet i see all references to the valves online say .008 exhaust and .006 intake.
is it recommended to set the valves at the later gap or stick to what my manual says?
my ultimate goal currently is to get the idle RPM low enough to set it at the 300RPM the manual calls for when retarding the spark. currently runs at about 620RPM and usually will stall out when drawing fuel.
Spark Plugs - Champion W89D
i set my gap to .030 as per my manual
i kept seeing people online talk about .040 spark plug gap so decided to try it and it definitely increases my pep in the car and has a ton more power to it and seems to run a little bit smoother (original coil)
now the question being why would i get so much better performance despite the manual stating a lower amount?
and should i keep increasing it until i get a miss or less performance? or is that ill advised?
also
i have 2 other sets of plugs wondering if they may be a better fit. most of the talk for the spark plugs seem to be for 28's and mention the 3077's which are no longer made
should i try gapping these to .040 or would it be futile
Autolite 3076 set at .030 they would run okay but lack of power and occasionally missing.
Autolite T7 set at .030 as well. they caused misses / backfires at high speed. i cant seem to find almost any info on these plugs but they came with the car.
i have a roughly 1-3 mile loop with hills nearby that i do to test the car when adjustments are made depending on which turn off i take, can be long or short.
as for the valves for a 25 with a 25 head single port exhaust my manual states set the valves at .010 exhaust and .008 intake when hot yet i see all references to the valves online say .008 exhaust and .006 intake.
is it recommended to set the valves at the later gap or stick to what my manual says?
my ultimate goal currently is to get the idle RPM low enough to set it at the 300RPM the manual calls for when retarding the spark. currently runs at about 620RPM and usually will stall out when drawing fuel.