671 on 440 Wedge Motor starts very hard when cold

[raceware]

I have a .060" over 440 with a 671 around 8.7to 1 compression (has 10 1/2 to one pistons but put .100" Flatout Copper shims plus Felpro rings gasket to take compression away) solid lifter cam 550 lift int .570 exh. around 290 dur. 2 660 holley boost referenced. I Have now a 44 top pulley & 33 bottom pulley well underdriven (didn't want allot of boost), about 18 deg timing. has a mini high torque starter twin Optima batteries pump gas 93 Oct. Starts very very hard & whipping throttle to keep running once everything gets hot it will idle but high. Wanting to street it only, but baffled why it starts so hard . Crank-crank-crank...Pump-Pump-Pump before it starts and usually hits2 or 3 times & dies before it actually starts. This is my first blower so I'm a novice for sure. Any Hints gratefully Appreciated


Thanks

[vinces427bb]

are the float levels set correctly?
what is the base fuel pressure set from the regulator?
is is smoking black when trying to get it worm to idle?
are these new carbs or used, needle and seat get sticky on used carbs
is it a locked out timing at only 18* or do we have initial timing of 18* ??

[raceware]

are the float levels set correctly?
what is the base fuel pressure set from the regulator?
is is smoking black when trying to get it warm to idle?
are these new carbs or used, needle and seat get sticky on used carbs
is it a locked out timing at only 18* or do we have initial timing of 18* ??

6 lbs fuel pressure, no black smoke, gray. The carbs are used but barely by the look when I bought them they were originally on a Tunnel ram setup, I had the carbs boost referenced & had them completely gone thru by a local carb shop (Chris's Carb Shop).As far as the float level they were set by the Carb shop , he knew my application so I assume they should be close.
Its initial timing is 18 deg has an MSD Mechanical advance.


Thanks
Raceware

[vinces427bb]

well it sounds like it is starving for fuel on start up..
also i understand that boost referenced carbs should be used in blow-thru applications
not thinking that is needed on a roots type PD blower, due to instant boost off idle??
seems like it fuel regulator will see the instant boost and raise the base fuel pressure higher than the engine would need at lower/idle rpm's
that's why i was asking about blackish smoking...
how are the plugs looking and what gap are you running

[raceware]

well it sounds like it is starving for fuel on start up..
also i understand that boost referenced carbs should be used in blow-thru applications
not thinking that is needed on a roots type PD blower, due to instant boost off idle??
seems like it fuel regulator will see the instant boost and raise the base fuel pressure higher than the engine would need at lower/idle rpm's
that's why i was asking about blackish smoking...
how are the plugs looking and what gap are you running

I was told that Boost Referenced would be better to run by some experts it was about half & half without the referenced carbs everyone always ran the carbs real fat they said because a roots style creates no vaccum between the carbs & the rotors & with that it could send no signal via vaccum, I believe it was to the accelator pumps,to pull more fuel needed on a load. The vaccum was created under the rotors & manifold & that was why it basically to boost reference is to basically block off that portion & create a vaccum port so a vaccum line could be ran from carb to a manifold vaccum port to create the signal needed. I feel like I wrote a book! Hope I explained like I was told so I thought that was the way I thought best after research. Your first thoughts of starving seemed right to me because I thought I addressed the other issues. The plugs really don't look bad to me certainly no wet or black looking, I put gap at .038". I am a mopar guy for sure but always when normally aspirated , I just don't know blowers for sure. Hard to start when cold in the past I cured with a manual choke, but I undestand you can't choke a blower motor & that your not supposed to pump the carbs while cranking due to backfires & that blowers ceratinly want to get hot before they start running right. went all over the map with the air screws trying ti riched them for starup but it really never changed anything.

Thanks

[vinces427bb]

maybe its a combo issue
could try tightening up plug gap to 30-32thou
if its lean that is harder to fire until the engine warms up??
also it wants more fuel to start and idle; i would fatten it up ...
try the plug gap first and see if it helps,
then decide on the fattening it up part...

[raceware]

I was also thinking can I put chokes on the carbs ? I was initially told blowers don't like chokes & shouldn't have them, maybe I was told wrong?

[vinces427bb]

chokes would be a restriction to the air inlet.
you should not need a choke,
the carb mixture idle should be fatter/richer to allow better warm up and stay running after starting