stu351

Can anyone help! I have a 351 cleveland with a 600 vac sec holley i am trying to put a later model one on it but it blows alot of smoke at idle and when you rev it so i put the original 600 vac sec holley on it and the smoke stops has anyone come across this before?

xacoupe

black or blue smoke??
If one carb is running very rich then it will blow smoke due to incomplete combustion.

mantaw2612

as xa coupe says its sounds like its running too rich,
check the jet sizes, float levels and that the choke isnt staying closed..

stu351

jet sizes in new carb are 64 old carb is 66

stu351

it is blowing blue smoke i got told that it may be doing due to the float levels so i have re-adjusted them but to no avail

shaynet

Blue smoke indicates oil burning. If it only blows smoke with the new carby on then it will be blak smoke indicating it is running to rich.

Is choke stuck on? I know nothing about holleys so maybe someone else can help you

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The cop said "Do you know why I pulled you over". I said " Well, that all depends on how long you have been following me!"

stu351

it is black smoke it is blowing the choke isn't a drama it has been taken off when u first start the car with the dud carbie it blows a big puff off smoke as well which it never used to do

xacoupe

check that your needle and seat doesnt have some sort of crap in it to begin with.
How does it run once it's started?

stu351

it runs fine it seems to have better pick up and it revs alot better then with the original carbie

fatjake

it could be a power valve blown

just look down the carby when running and if its dripping fuel its blown a power valve or floats to high

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worked xe 351,
9.5s on 1/8 mile with bald tires and no converter, smoking the rears the whole way
HSV i just ate one