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mcculloch timing
I run pump gas so I have all my motors set at 26 ..this mc6 for historic class .im thinkin bout trying alky .can I take 5 degree flywheel key and alky carb to track and change just those two things and convert to alky for testing ..
i'm posting a total answer for you. you probably know all this but others may profit from one bit or another.

you can run pump gas and alky at same timing.
you could consider advancing the motor on alky as it'll run cooler .
but i wouldn't bother as you also risk killing the motor .
i think my mc10 is at about 25-27 degrees but i've never fussed with it much and you know it's fast.
has the standard mc10 flywheel.

more important to have good port work the mc10 is 9 ported with a opened up exhaust.

also good carb function is huge.
my carbs are at about 8-10# pop off on alky.
i ALWAYS seal test any leaks are bad.

my carbs are usually t-slotted internally if you like i'll send you pix or post here.
typically i use a cr1a cresent but any good alky will do.

i usually replace the shutter and i fuss with it till i see no daylight showing when it's closed.
they are ovalish and almost never go in square first try.
the pressed double dot or the slot indicator goes topside
shave the shaft if it isn't to increase air flow.
check the shaft for wear both through carb body and on the shaft.
toss and loose or worn shaft it makes a difference.
the throttle shaft needs to be totally free it should make a snap sound when released.
i usually replace the return spring and check the clip they are usually used up and about to fail.
if the throttle shaft clip retainer slot is worn out i will replace throttle shaft , otherwise the shutter wears the bore and itself opening up clearances inside.

inspect your reed block remove any casting flashing and check the flats where the reeds contact.
my favorite is a six pedal for the older macs.
i also oval and campher the pulse holes and check the gaskets for perfect alignment.
i like to oval the hole so theres zero chance of blockage.
a tiny blockage here will slow down the pulse ALOT.
check the internal area of manifold to often there's casting flash that is slowing down velocity.

i'm also really anal about flatting the plates on the carb and intake manifolds areas.
also flat the intake area, stuffer and head on motor block.
actually ANYTHING thats supposed to be flat on the motor i check and fix with flatting.

polish the carb air passage too

i'm posting all this in interest of fairness. if your engine runs as good as mine i'll stop hearing about me running a cheater which i don't!!! Tongue
Dave L.
good advise from David. Generally timing advance is going to take you no where. Leave the timing at 26*. I'll run 24 on a peaky engine. All the big advance numbers just get more heat or detonation. The 5* flywheel on gives a hotter spark. If you were to go maverick you can get a 5* advance from where your point timing is. If not going maverick your timing stays basically the same as you set the points. I never worry about the 5* flywheel. Most of the time we have a std flywheel with a slotted coil to get to the same place.
(02-02-2017, 03:54 PM)steve welte Wrote: Most of the time we have a std flywheel with a slotted coil to get to the same place.

A slotted coil, how?  Do you use any extra hardware to hold it down then, oversized washer or anything?

Bob Alexander
the coil is already slotted for up and down. You slot the coil to move it for sideway movement. No extra hardware. YOu can use a larger od washer if you wish
..bob ., from what I noticed the stock holes you can bang it all way to one side and get 28 so I believe  it wouldn't take much of a slot to get 30-32.. ..???
Alky and timing wont get it done.specially against a stroker, give it up. Neither of you can beat Bob anyways, lol luv u bro
we have a lot of fun in historic class no matter what we build and ride ..

and cant wait to chase you and chip on sidewinders ..we just gotta teach bro in law to wait up for us
John, if I'm the Bob your referring to it's not stroked but does have a few extra holes in it. ??
And thanks to you I will soon have another bullet just like it, thank you.
Oh, I do have a stroked 6 that is ready to go original engine for the kart. bored 100 over ? so 
I  haven't run it for fear of sticking it,  can't bore it again. Lol
Can't wait to get going.  

Ps. Miller is right we have a blast in the historic class. Hope to join you guys in sidewinder
this year. Will take a lot of practice on my part.
...hey bob good to here from you .. when john was talkin mc6 stroker he was referring to him self with loras kart .. lol..dang cheaters ..hehehe..
still fun 1st place 5th who cares we have a blast ..
bob im goin all in this year .fixin up an alley kat . I freshened 6 with way better used rings different header huge ugly hi rise intake thing should fly ..lmao ..

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