40ci Mod Mercury Magneto Advance Mechanism?

[BmJuby]

I am wondering if people could post pictures of how they setup their modified mercury engines with regard to magneto advancement. I am curious how this is accomplished without using the lower pan. Once I see a couple good pictures I am sure I can figure it out. Just have never got a comprehensive look at one before. I would also want to see how the throttle hookup is done where the bowden cable attaches to (wherever) on the engine and advances the mag.

Or, do most racers set their mags and lock them down at the desired timing? I'm pretty sure I've seen both.

Reason I ask is because I have a Mark 55H mod that I was planning on just locking down. But I know some people fabricate mechanisms so that they can start the engine at a lower timing and go from there. It would just be nice to be able to start the engine more easily on a lower timing and then let it advance with the deadman throttle advancing.

Thanks,
Brandon

[PRO-MOTIONRACING]

When swinging the mag I use a cut down pan to mount the cable and pivot arm. When locking down the mag I find it best to use a "loose" or "floating" system as the towers will crack and break when mounted solid... I hate when my mag falls off.

[A/B Speedliner]

44 CI throttle and advance

Brandon, this is how Doug Kay did the connection on the 4 carb 44. He used the normal throttle connection on the pan with the curved bent plate on the side of the mag. He then made a pulley cable system to accuate the carbs. You can see the cable just below the top carb.
David

[blueskyracer]

Brandon, this is how Doug Kay did the connection on the 4 carb 44. He used the normal throttle connection on the pan with the curved bent plate on the side of the mag. He then made a pulley cable system to accuate the carbs. You can see the cable just below the top carb.
David

Doug does some amazing work..Can hardly wait if you know what I mean!

[form-e one]

luv to see some of those 4 bangers in your pics run,,, maybe post them when ya try them out,,,,incredible craftmanship,,, prob incredible price?????

[Sonny]

I have been admiring this motor since I first saw it a year ago. I am thinking about starting with the 650xs. It seems similar.

[form-e one]

if ya thinking raceing it with the v-rude,,, it deff wont compete,,, but yaaa i like the merc as well

[A/B Speedliner]

Doug's Engines

My brother has been racing the four carb engine and a number of other 30, 40 and 44 cubic inch engines for the last 2 years in NBRA and also at the APBA race in Hillsdale MI. He also has run a 20H I built for him and a 60 CI inline six.
David

[BmJuby]

Thanks for the pictures David, it explains a lot. Do you have a picture of the Bowden cable hookup from the other side?

So Doug just cut up a lower pan to just have the essential attachment points, turning it into that hardware attachment "arm"? Or is that a custom piece? I understand all the arms and springs and hardware, including the actuator. I just now need to see what/how/where that large arm coming from the engine (where all the hardware attaches to) is accomplished.

Just noticed the cable you mention going from the mag to the carbs. VERY cool. Fortunately I won't need anything custom for that part, I'll be using the standard carb advancement elbow from the mag tower.

Appreciate it,
Brandon

P.S. I agree with everyone else. Every once in awhile I browse the thread with all the pictures of these guys' stuff. This engine in particular is amazing.

[A/B Speedliner]

Bowden cable hook up

Brandon
The Bowden wire is connected exactly like a stock hook up. Doug makes a stainless clamp and uses a stock lever arm to accuate the mag. The inner cable is connected to the lever with the standard brass block and two set screws, the block slips over the pin on the lever.
David

[BmJuby]

Thanks David. I know how all of that attaches and functions, it is as you say, more or less exactly how the stock 55H functions. I need to know what the aluminum piece that all is attaches to comes from. You mentioned Doug taking it from an original pan. Just confirming that is what it is, or whether it is a custom piece that Doug fabricates. Sorry, I'm just not getting it, haha.

[A/B Speedliner]

Plate

Brandon,
I think Doug machined a plate to take the place of the bottom pan. You could use a modified pan to accomplish the same thing.
David

[john527]

mag mount

simple!

[BmJuby]

Thanks guys. I definitely have an idea now. I do like the idea of using the bottom crank bolts as a mounting point, but I'll think of something eventually. I would prefer to use the filler plate I have installed as it has the mounting bolts for the steering arm attached at the back. Maybe ill tap some bolt holes into the front of the plate and start from there. Really appreciate it!