twin ignition system in 51 chevy

[jbwelda]

heres a real strange one imo...

the amt 51 (i think it is, dont have it in front of me) chevy fastback straight six motor contains an option for what appears to be a twin ignition system: twin plugs for each cylinder (as evidenced by 12 wire outlets on the distributor cap) and dual points (as evidenced by the twin condensors on the distributor body.

this is aircraft style stuff.

question: is there or was there a real life prototype for this system? i dont believe i had ever heard of such a thing until seeing it on a quad cam porsche motor of the early 60s. or did the amt engineers just make this up?

by the way this is for the "custom" version of the straight six stovebolt motor.

[62rebel]

it was in the 51 hardtop kit with the drag style fuel injection setup, i have a couple of these in the parts box. they were available but like you say they were high performance and not generally street use parts. i THINK the first issue of this kit gave a good description of the parts on the instruction sheet.

[Guest zebm1]

In tha early 50s and thru tha decade after, automotive engineers pretty much had "free money" to shape and forge High-perf parts in tha 'stock' assembly lines....all Ford P/U trucks until 1963 or so came stock with Forged cranks and rods......I used them exclusively in my engines....no Hi-po surcharge.

Yu had 3 production lines of head design to choose from, tha smallest chambers I ever found, that would accept 312 valves was tha '53 Mercury 272, actually it was something smaller, weird....Biscuit? was it a 251 or sumsuch?

And then there was Ford's AIR-cooled 3 spd. automatic, properly modified....it kicked arse, all aluminum....yeehaww

and yu could get bolt on Spicer rear axles wid 'stock' 4:11, 4:88 gears

outa Ford Stationwagons

tha 2 plugs per cylinder head for a Chubby 6 block yall are talking about, was an early 'aftermarketer' design.....as I remember it, as I heard it....and Indy engine designer did it first.....eh Biscuit?

I'll bet a bunch of yall didn't know that Ford turned down Z.A Duntov's 265 thin-wall cast V-8 as an "Inherrently Weak Design as regards tha Crank bearing supports" Ford was correct, but tha process of casting chubby V-8 blocks was ohhh soooo much faster and cheaper......

sooo...we hot rodders littered tha land with crunched Chubby bottomends.....YeeeeeHaaaaaaW! :twisted:

[Mercman]

Heres one built up, I put it in a 55 Chevy stocker.

[JAFFA]

hmmm, i do know that my dads army-JAWA motorcykle has twin ignition,

so if one brakes, theres anotherone right there.

that bike's from somwhere during the 60's, i dont know if that info iz of

any help?

[jbwelda]

>so if one brakes, theres anotherone right there.

yes thats why they are used in aircraft applications, fail safe redundancy. its kind of hard to pull over to change a plug at 20k feet!

i never saw the 51 chevy with injection; the one ive got (reissue) has only 2 carb setup aside from stock.

thanks for the photo, man that was a pain drilling the 13 holes in that cap eh?

[James W]

Popular Mechanics mag March 1954 has an article outlining the use of GMC inline engines for high performance use. There are 3 pictures of dual coil/12 plug distributors. The text of the article says "for real efficiency you'll need two coils of high output plus a twin-point distributor." The pictures show single plug heads. I could not find this article on the web. If you have trouble getting a copy send a PM and I'll get a copy to you. As a side note, 6 months after this article was published, the small block chevy became the engine swap of choice. :roll: