Need help with the jets and metering rods for a 305 chevy

[jamon8]

my car was running way to rich and I know that I have the wrong jets and metering rods for a 305. the carb that I am using is a 17080213. I need to know what size jets and metering rods to use so I wont fowl out another set of plugs.

please help. I really like quadrajets and dont want to put an edelbrock on my car because I wont be able to hook up the cruise control

thanks
james

[Ethan1]

 The stock sizes in that carburetor were .072 Jets, Primary Rods 50M, Secondary Hanger K, Secondary Rods DP. We will see what others recommend for that carb.

[jamon8]

I really want to know what size jets and metering rods I should put in that carb so that it will run my 305. its not an h.o. motor. its in a 1983 pontiac grand prix that I took the computer off. I put an RV camshaft in it and a edelbrock performer intake. everything else is stock.

the primary rods look like they are 48's or 49's. I also have a set of 55's that I can use I just dont know what size jets to use with these rods. my jets are all scrached up so I could not tell you what they are for sure.

the secondary rods are dp's and the hanger is is a h

[Ethan1]

 Yeah, I was just giving the stock specs, in case Cliff or someone needs to know, instead of having to look them up.

[Cliff Ruggles]

I'd install the stock metering rods if they are in good shape.  Those carbs used "M" series rods.  At most go up one jet number for initial testing.  This new fuel has less BTU's than older formula's due to the ethanol content and reformulation, so it helps to add more of it for best results.....Cliff

[jamon8]

well I followed cliffs advice and ordered my jets today. what would be the correct level to set my float at

[Cliff Ruggles]

It really depends on the actual fuel pressure.  If you don't know what it is, start at 9/32", as some of those later engines used high pressure fuel pumps.....Cliff

[jamon8]

I believe it is a high preasure pump. I will try 9/32 as my float setting

[jamon8]

i put size 70 jets in the carb and I have to say that it starts alot better than it did. I think it has less power but I think that it was getting too much fuel and not burning it all with the bigger jets.

it seems to be lacking power just with the throttle cracked open a little bit. feels like it is kind of bogging down and not running like it did before with the bigger jets. there was a few times when it fell on its face and quickly recovered. and once going up a hill it lost power but I could not get it to repeat that after several tries.

All in all I think that it is running much better and I think I am going to raise the float level a little bit and come out another half a turn with the apr screw(hope that is what its called).maybe that will help get a little more fuel to the carb.

thanks for all your help and I will keep you posted on the outcome of the aboved mentioned changes

[Cliff Ruggles]

Select jet size first, by doing some heavy throttle testing, climbing steep grades, passing without the secondaries, etc.

Once you find the ideal jet size, fine tune the APT for light throttle (normal) driving, smoothness right off idle, etc.

The APT is the key adjustment for this deal, as we spend most of our time driving on the primary side of the carb at light throttle openings.....Cliff

[jamon8]

its my smoothness right off idle. it seems like when I am just opening the throttle blades and accelerating slowly and hit the gas to take off it hesitates a little bit.

would this be the apt adjustment

[jamon8]

well I turned the apt screw out to 4 1/4 turns and the hesitation is gone. it is really running great. the only problem I have with it is when I go to start it up on a cold day, like we have now, it really starts to stuble and surge like a couple of plug wires are off the plugs. what would cause this?

thanks for all your help cliff

[Cliff Ruggles]

Adjust the choke pull-off and the fast idle rpm's so it starts and runs smooth on the high step of the fast idle cam.....Cliff

[jamon8]

I adjusted the choke pull-off, but it seems like it takes too long for the choke pulloff to engage and untill it engages the engine runs really rich and bucks, shakes and feels like its missing.

the vaccum line on the choke pull off seems a little loose. I will try to get a new line on it and see if that helps.

does the choke pull off not engaging right away mean that it is no good and should be replaced?

[Shark Racer]

The choke pull-off should engage pretty much immediately.

Did you test it? Remove the vacuum line, fully retract the pull off and then cap the vacuum port with your fingers. The pull off should not retract. If it does, you need a new pull-off.

The one I received from Cliff is GREAT. I highly recommend it.