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Re: A shameless image thread for the enginephiles
Posted: 14 Mar 2018, 05:18
by djos
FightingHellPhish wrote: ↑14 Mar 2018, 05:08
djos wrote: ↑14 Mar 2018, 03:53
FightingHellPhish wrote: ↑14 Mar 2018, 03:46
Are there even coils that can keep up? Those magnetos are 44 amps worth of current a piece. The engines no longer have the diesel issue.
I did wonder about that.
Oh, how recently did they solve the plug burn out issue? Even 2 years ago this was an issue as far as I was aware.
IIRC it was mentioned in a conversation with someone I spoke with in the industry. The issue had been the material of the plugs but with platinum, iridium, and other things developed they were able to fix the issue at least for a single run.
Nice, that might explain why they dont tend to blow the superchargers off motors as often as they used to.
Re: A shameless image thread for the enginephiles
Posted: 14 Mar 2018, 07:27
by Maritimer
I went to a race last year and most of the plugs they threw away still had electrodes on them. Don't think they burn out as often, however there were still three that went off when I went.
Re: A shameless image thread for the enginephiles
Posted: 14 Mar 2018, 19:43
by strad
The reason they drop a cylinder is not always the plugs.
The mags put out enough to arc weld with.
Re: A shameless image thread for the enginephiles
Posted: 15 Mar 2018, 05:33
by FightingHellPhish
strad wrote: ↑14 Mar 2018, 19:43
The reason they drop a cylinder is not always the plugs.
The mags put out enough to arc weld with.
Yea there's a variety of reasons cylinders wont fire. Hearing a TF engine explode is something else though (and a long clean-up xD)
Re: A shameless image thread for the enginephiles
Posted: 15 Mar 2018, 08:20
by strad
nothing like being on the starting line.
Vibrates ya down to your soul
Re: A shameless image thread for the enginephiles
Posted: 15 Mar 2018, 13:04
by Tommy Cookers
magneto output has over the useful range inherently faster voltage rise than coil output has
because field building (the magneto's primary) is inherently faster than field collapsing (the coil's primary)
this simple fact (the secret of magnetos) has apparently been forgotten in this internet age
fast voltage rise means that magneto ignition needs less peak spark voltage than coil ignition
though coil ignition can give a longer duration spark that may be unimportant
25 years ago top dragsters were using 14" distributors to enable 85 kV coil ignition
and I had a trembler coil energising magnetos at zero crank rpm on my RR Meteor engine
somebody post an image or we'll be in OT trouble !
Re: A shameless image thread for the enginephiles
Posted: 15 Mar 2018, 13:25
by dren
Re: A shameless image thread for the enginephiles
Posted: 15 Mar 2018, 19:40
by strad
I haven't paid much attention in recent years ,but for a time they actually ran 3 Mags.
Doesn't a Magnetos output go down as rpm goes up?
Re: A shameless image thread for the enginephiles
Posted: 18 Mar 2018, 08:42
by FightingHellPhish
I need to find my TF floater plate.
Re: A shameless image thread for the enginephiles
Posted: 18 Mar 2018, 19:03
by flynfrog
Any ideas what the pockets are for between the primary's? Cooling?
Re: A shameless image thread for the enginephiles
Posted: 18 Mar 2018, 19:42
by hurril
flynfrog wrote: ↑18 Mar 2018, 19:03
Any ideas what the pockets are for between the primary's? Cooling?
Pushrods?
Re: A shameless image thread for the enginephiles
Posted: 19 Mar 2018, 01:30
by FightingHellPhish
flynfrog wrote: ↑18 Mar 2018, 19:03
Any ideas what the pockets are for between the primary's? Cooling?
With where they are positioned I'm going to say to save weight. Ounces equal pounds and all that.
Considering the extra bolt holes though.. I'm not 100% sure.
Heres a cylinder head with a not quite direct injection setup.
Re: A shameless image thread for the enginephiles
Posted: 19 Mar 2018, 03:58
by strad
Any ideas what the pockets are for between the primary's? Cooling?
Not sure which you are talking about.
Re: A shameless image thread for the enginephiles
Posted: 19 Mar 2018, 06:24
by johnny comelately
Tommy Cookers wrote: ↑15 Mar 2018, 13:04
magneto output has over the useful range inherently faster voltage rise than coil output has
because field building (the magneto's primary) is inherently faster than field collapsing (the coil's primary)
this simple fact (the secret of magnetos) has apparently been forgotten in this internet age
fast voltage rise means that magneto ignition needs less peak spark voltage than coil ignition
though coil ignition can give a longer duration spark that may be unimportant
25 years ago top dragsters were using 14" distributors to enable 85 kV coil ignition
and I had a trembler coil energising magnetos at zero crank rpm on my RR Meteor engine
somebody post an image or we'll be in OT trouble !
Those big diameter dizzys were to stop voltage jump.
Re: A shameless image thread for the enginephiles
Posted: 19 Mar 2018, 06:41
by FightingHellPhish
strad wrote: ↑19 Mar 2018, 03:58
Any ideas what the pockets are for between the primary's? Cooling?
Not sure which you are talking about.
the port like holes in between the primaries.
