What's up everbody...hope every one is doing well. I have a 327 sbc backed by a 350 trans in a 30 model A. (Holley 650 carb) From stop to about 35mph....if I stab at the gas pedal the car bogs and back fires. I was thinking that it coubl be that the jets are too small. (Stock jets) This would cause the car to run lean. Possible the fuel pump in the carb is busted or I just don't know. This is my first Holley and love it at high speeds....low speeds sucks. I am running a 9 inch rear end with 3.75 gears. I believe that the tires should be breaking loose every time I step on the peddle but that is not the case. Any ideas? Thanks...Happy Holidays.
have a look see at your power valve..its probably shot..those Holley carbs have this problem when they are subjected to backfires.
I was just about to mention the power valve...is that some thing I can change out with a rebuild kit. I have a local speed shop that can get me a rebuild kit...and I could take a hammer to it until I figure it out.
yeah if you got a speed shop they should know what you need..give em the crb number and any other info they should be able to get you the right parts, at this time i would make sure you re-build the carb anyway..and make sure your timing is right and good ignition parts too. you need to eliminate that backfire issue or it will do it again.
let the bashing begin BUT that's why I run Edelbrock. No problems that can't be adjusted out or at least not yet
Rich you will not get any argument from me on that one!..Holley carbs are nice but they are not really made for street driven cars IMO . they are made for all out WFO trottle..racing. rochesters do a nice job of feeding an engine and only give the engine what it will take to perform and not too much more..(read as not wasting gas out the tail pipe). they are nice street carbs. edlebrock makes a nice carb too.
If it is not the power valve, change the accelerator -pump discharge nozzle (shooter) to a smaller size if the engine accelerated well than bogged and to a larger one if engine bogged than accelerated.
I would be checking the ignition timing, a little more advance might cure your problem. If the timing is Ok, then I would start looking at the carb.
What model Holley ? You say 650..is that a spreadbore, Vs or double pumper? Remember do the rest of the tune up before you even start on the carb, and before you even start on the tune up do a compression check and check for air leaks . Do the mechanical tune...lifters, ignition etc , then timing, then the carb last. Float levels, pump lever adjustment etc then idle speed and curb idle mixture. If the pump is not working or weak take a look at the check valve in the pump chamber on the bottom of the bowl, the ball bearing type often gets corroded in or if the pump lever is adjusted too tight it will bend the retaining bar up and jam it closed , blocking fuel from filling the pump. If the power valve is busted (from a backfire??) it will run power valve rich all the time, vacuum holds the power valve closed , it opens when there is no manifold depression ( vacuum), or the valve is not sealed to the manifold pressure/depression.
Damn....thanks everybody...I ask for a quick fix and every body comes out with thier A game. OK my Model A has been turn key since the day it hit the road to Paso 3 years ago. The timing is ok...and the mecanical tune all specs out. The only thing in the back of my mind is that I might not have enough spark coming from my HEI...is that possible. High speeds my Tudor is a dream...when I want to launch...it booooooggggggsssss.....rrrrrrrr.......offf it goes again. I just want to stomp on the peddle and burn tire down the block. If not I know Holleys are great for all out racing...should I just bite the bullet and buy an Eddel Brock carb and be done?
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