what should I do carb problems

[Jeff 69]

Hello I have a 1969 383 Road Runner 4 speed stock motor with a little cam in it. Its a voodoo cam. .475 in .494 ex. Just been rebuilt all parts are new, and it sounds great. This car has NO pep in its step. I know have a 750 cfm edelbrock carb on it. Would this carb be to big for the motor ? It runs fine down the road but I can not even turn the tires over. Its a real pooch. Looking to see about maybe a 650 cfm holly? Can you help me out on this 1969 pooch !!! I need to wake this car up. Thanks Jeff

 

[Garys1969RR]

Sounds like ign timing could be the prob here. Thats assuming you have 120 PSI or more with each cylinder on a compression test. Limit the centrifugal advance within the dist to 18 degrees total. Then set initial timing to 18 to 20 degrees BTDC. You want total to be at about 38 degrees.This will help low end and mid range torque. Best to plug the vacumn advance while doing this, then you can add it in later if the engine will take it with out pinging. Set your jetting to original factory specs. A smaller carb may help low end torque.

 

[Snowtrooper1966]

You should be able to rip the rubber off those rims w/a 4 speed manual, especially with a cam. Dunno if it's the carb. How was it before you put the cam in? Could be clutch...

 

[Garys1969RR]

These motors like alot of initial advance, I have found. I am running 20 degrees initial with 38 total on my 451. 509 cam. 12.5 to 1 C/R. Works great with no pinging. Also using 97 octane fuel.

- - - Updated - - -

Do you have the original 906 heads? Do a compression check and let us know what you have.

 

[63RedFury]

750 cfm will be fine although I would go with a Holley double pumper.your cam is slightly bigger than stock but should be Ok.What gear do you have in the rear? If you wanted to wake the motor up you should have went with a bigger cam,headders,750 Holley double pumper, high rise intake,and a good ignition system.

 

[brasil]

even with a 2.76 rear end... the tires should spin Ignition timing x2 ! Fast Advance curve...@ 36 deg all in around 2700-2900 upm

Greetings Juergen

 

[Jeff 69]

I just want this car to run good on low end I do not know why its a pooch. I have a new clutch as well. I have a orange ign box.I have stock exhaust and intake manifold. comp is 130 my 750 edelbrock carb is what they call a performer.my rear gears I think 353? stock

 

[Jeff 69]

Sounds like ign timing could be the prob here. Thats assuming you have 120 PSI or more with each cylinder on a compression test. Limit the centrifugal advance within the dist to 18 degrees total. Then set initial timing to 18 to 20 degrees BTDC. You want total to be at about 38 degrees.This will help low end and mid range torque. Best to plug the vacumn advance while doing this, then you can add it in later if the engine will take it with out pinging. Set your jetting to original factory specs. A smaller carb may help low end torque.

thank you

- - - Updated - - -

These motors like alot of initial advance, I have found. I am running 20 degrees initial with 38 total on my 451. 509 cam. 12.5 to 1 C/R. Works great with no pinging. Also using 97 octane fuel.

- - - Updated - - -

Do you have the original 906 heads? Do a compression check and let us know what you have.

thank you

 

[63RedFury]

It should run well with that combo.Work on timing and dialing in the carb.

 

[Hemi Rebel]

The switch to the 650 will give it a snappier low end throttle response. If you have the carb I would put it on just for comparison sake. But like others have said, make sure the ignition is set right first before messing with the carb.

 

[Jeff 69]

ok thank you.

 

[Garys1969RR]

A timing light is needed to set this up properly. Also a degree tape for the Harmonic Balancer. Or you can paint a white line on the balancer where 38 degrees advance would be. Then rev the engine until it stops advancing, and make sure your 38 degree mark lines up with the TDC mark on the timing cover. There is usually a small hole drilled in the timing cover tab where TDC is.

 

[charger360]

i agree more timing! and that is not a lot of psi 130! you seem to be a bit low on compresion do you know what the true ratio is?

 

[GTX MATT]

You have a low compression (8:1 or less) 383 with a decent cam and that junk Eddy carb. Get your timing in as quick as possible, lose the 750, and see what you can do to get the compression up. What pistons did you use?

Eddy carbs are fine, but the 750 AFB has given many people issues. 650 manual choke AVS or run a Holley.