low power on take off??


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By mgcookwv - 9 Years Ago
Ford Fairlane 1955 V8 272 Y-block
I've changed the intake manifold to a 1957, new 0-8007 Holley 4 Barrel 4160 Carburetor
with a new msd distributor.
My problem is when I give throttle pulling  out, I have very little power and have to hold the pedal to the floor and at about 40 mph it feels like it starts picking up rpm's and gaining speed and runs terrific on the top end but getting there is an adventure
On my old setup this wasn't as much of a problem as I attributed slow going to the gearing, I just expected more power with this set up on starting speed.
Can a new gear in the rear end help with this set up and give me more torque on take off?
If I pull out in front of another vehicle accidently and have to floor the pedal to get going I'm in trouble.
 .
By charliemccraney - 9 Years Ago
You have tuning problems.

Which advance curve are you using and have you verified that that curve is actually what you are getting?

There is no such thing as a ready-to-run carburetor and tuning is required.  I know they will advertise that it is ready to go but it is not.  Have you tuned it?

What is your vacuum at idle?

Different gears can help but it is probably not your problem.  What is the current gear ratio?
By Lou - 9 Years Ago
What gear are you using in the rearend?
By 57RancheroJim - 9 Years Ago
I wonder if the trans is actually taking off in high gear. Try shifting manually into LOW and see how it takes off. Assuming it's an auto trans.. Changing intakes and carbs can mess up the trans throttle pressure settings.
By mgcookwv - 9 Years Ago
Tuned very little, just enough so it wouldn't die when placed in gear.
By mgcookwv - 9 Years Ago
Educate me please? Don't have any idea abount advanced curve.
By Ted - 9 Years Ago
Assuming you have verified that the car is taking off in one of the lower gears, then consider some of the following.

Have you timed the engine with a timing light?  If the base ignition timing was set with a timing light, was the vacuum advance disconnected when doing so?  Where is the vacuum advance hooked up?  Have the timing marks on the damper been verified as being in the neighborhood?  Those older dampers have been known to slip thus throwing the timing marks into a new neighborhood.

On the MSD distributor, have you changed out the ‘as supplied’ advance springs with any of the lighter ones supplied separately with the distributor?  The MSD distributors as supplied come with the stiffest springs which makes the advance curve on the lazy side.  I find that the light blue and light silver springs are a good starting point for most Y engines.
By mgcookwv - 9 Years Ago
You are going to understand that I'm a flake when it comes to being a mechanic. When I purchased the distributor. I opened  the box and read about the springs, I put them up for future use and low and behold I can't find where I put them, kind of explains why my car won't run so well.
By speedpro56 - 9 Years Ago
AS Ted said, take the heavy silver springs off and replace with the light silver and light blue then you should see a better low end.