Spark Plug Wire Lengths

(Rob Reilly) #1

Its snowing again and we’re in for a week of below zero F so for an indoor project I thought I 'd make new plug wires for the '38 2-1/2 L.
I see in the parts books that the wire lengths changed from the L engines to the P engines and changed again with the H engines.
Did anyone ever come across a reason for that, changing the wire lengths?

(Ed Nantes) #2

Rob we’ll take some of that snow, Melbourne airport was 46c yesterday.
Difference in plug leads - different dist? SS had DUH6A dist, but will vary a bit on which way you face the dist. Ideally plug leads at about 2 o’clock. Ideally Hyperlon leads or something that will take high temperatures. Not those ye olde ones that look like wasps.

(Peter Scott) #3

I can see the sense in aiming them about 2 o’clock but perhaps with the manual advance/retard there might be more freedom of movement at a different angle. Say 4 o’clock?


(Ed Nantes) #4

Can we compromise as say, a quarter to three.
But we haven’t really needed to use manual adv/ret for many years. And yes, they are the yellow leads I mentioned.

(Peter Scott) #5

Indeed. These engines are very insensitive to ignition timing and they aren’t inclined to detonation so the manual advance doesn’t do much more than change the idle speed.


(Rob Reilly) #6

Ok I hadn’t thought about the manual advance on L and P engines vs the vacuum advance on H engines. Perhaps the difference between the L (Standard built) and P (Jaguar built) was the angle of the cap, which is determined by the installation of the drive shaft.
By wasp wires I’m guessing you mean the yellow and black cloth covered wire sold by Rhode Island Wiring.

I suppose cloth covered might be authentic period, but I have to draw the line somewhere on authentic vs practical.
I have a spool of black rubber covered Packard 440 cable.

I just want to get rid of the yellow stuff that’s turned pink where it got hot.

I’ll try to send you some snow; you can pay for it with SleighPal.
BTW one time when the Minnesota Vikings played the New Orleans Saints the Vikings fans brought down a truckload of snow for the Saints fans, some of whom had never seen it.