47-55.1 Eliminate draft tube options

[geezer#99]

Whenever I needed to find tdc #1 I’d use my compression tester, hang it up high enough to see from the cab and bump it over with the key until it showed compression. Then moved the crank by hand to line up the marks or the bb in your case.

[leegreen]

if you take out all the plugs it turns over easier, if you leave #1 plug in you will know when it is on compression stroke

[TX3100Guy]

Originally Posted by geezer#99

If you use a factory side cover then an hei fits. They’re indented compared to your ribbed cover.


https://www.ebay.com/itm/324321238128

I know, but I like my chrome Chevrolet one.........lol

[TX3100Guy]

So, I inserted three silicon stoppers in cylinders 6, 2, and 4 (leading up to #1 being at TDC on the compression stroke). I used a remote starter to bump the starter and one by one those silicon stoppers popped and shot across the shop........ Top Tip, make sure you aren't standing anywhere near the spark plug holes when the stoppers POP.

[TX3100Guy]

I gave up on the idea of an HEI distributor since I want to run the magneto in the long run. In the mean time, I purchased an electronic (optical) distributor and coil. Now I need to complete the wiring and attempt to fire the engine up again. Fingers crossed.

[TX3100Guy]

Question: The gap on my NGK spark plugs is .020 for the Vertex magneto. What gap should I reset the plugs to for an optical distributor with a 1.5 ohm coil? I don't know for sure, because under my ownership this engine always had the magneto.

Also I found a reference that suggested tightening the plugs to 25 ft/lbs. Does this sound right?

[leegreen]

you have a unique setup, what is compression ratio and boost expected?

.035 would be typical for a 235/261
Electronic ignition can spark a wider gap, bigger spark for cleaner burn. 045 for HEI SBC

high compression & boost may need smaller gap for if the spark can't jump a big gap in a high density charge, but I doubt your going to be driving this beast that hard in the near future. I wonder if 020 is more to make it easier for magneto to spark?

030 to 035 should be pretty safe
25 foot pounds sounds about right, I just snug em up with a 3/8 ratchet on iron heads

[TX3100Guy]

Originally Posted by leegreen

you have a unique setup, what is compression ratio and boost expected?

.035 would be typical for a 235/261
Electronic ignition can spark a wider gap, bigger spark for cleaner burn. 045 for HEI SBC

Compression is very close to 9:1 and boost will likely be up to 8 psi, but that's driving it harder than I will likely run the truck. While its styling is that of a hot rod, I have no plans to take it to the drag strip.....LOL