Hello, I have a 85 12A stock. The previous owner put on a holley 600 part#0-80457S
http://www.holley.com/0-80457S.asp . I had flooding issues so i replace the jets from 65 to 53. Now the car wont go past 4k without bucking or hesitation. Also there are a few vacuum ports on the carb or watever u wanna call them that aren't connected to anything or blocked off which is y i think my seconaries are not opening. I need help on this one. If anyone has pictures of how they have theirs set up please post up. If anyone has any ideas on the bucking, please tell me.

 

can you post a pic of the vacuum ports? I would assume they are the ones in the base plate. There should be a vacuum port in the plate between the bowl and body, the distributer vac advances should be hooked there. The oil filler vent and brake booster should be hooked in the mani. All the other ports should be blocked.

How is your OMP hooked up or is it setup for premix?

 

here are the pics. The way the previous owner hooked up the omp is by drilling 2 holes on the top near the choke. my omp is working fine n i c it dumping oil slowly. the dist doesnt have any vacuum lines hooked up to it. the oil filler is blocked off wit a screw. the vapor canister( i think thats wat is called) is still hooked up from the line underneath the oil filler tube to the black canister. I kno the carb is too big but i just want it to run good.

 

RB hooks up the omp using a nipple in the fuel bowl sight.

The vacuum line in the 4th pic should be hooked to the trailing vac advance leave the leading unhooked. The lower tube coming out of the oil filler should be hooked to the vacuum line going fron the mani to the brake booster with a T and also run a PCV valve in the line between the T and the oil filler.



you can see the tube from the oil line to the T in this pic:

 

do you have any more pictures of your set up. thanks

 

if ur going to run vac advanced, the pots on the dizzy should be T'd together and connected to the vac port on the primary metering block. u can cap off all the other ports. RB carbs don't have all those vac ports on them. and as mentioned, run the omp lines to the primary bowl via the site plug. u can see pix in my photobucket. any others i can get for u.

http://s83.photobucket.com/albums/j291/rxtasy/

 

Ok. So let me ask u something. The bucking and the hesitation is it the result of a weak fuel pump. It is original as i can see. I changed the filter.

 

Start with the vacuum leaks first. You could have a fuel pump problem. A holley should run at 6psi and the stock pump can't reach that.

 

whats your fuel pressure?

Holley's are supposed to be ran at 6psi. But i have had best results at 4psi-4.5psi on a stock to small street ported 12a.

 

I dont know the pressure but i know its a stock pump. I know whenever i hit the gas, it seems like its not getting gas. This morning i had pribs turning it on. I pump the gas like twice and crank. It turns on but shuts off n when i hit the pedal, it chokes n shuts off

 

The OEM pump barely fuels the Nikki, it won't even come close to supplying a Holley. No point in tuning until you get a proper fuel supply to the carb.

 

Well i ordered a carter pump which the guy at the the performance shop said its the same spec as the mallory one n less by 60 bucks

 

The carter is a good pump but it is very noisy. I ran the carter on my '83 and never had a problem with it. When you install it, run a relay with a fused wire right from the battery.

 

There are ways to quiet noisy pumps down. You can mount it to the frame rail if you move the cut & check valve. Isolate the pump using an old mouse pad or rubber bushings between the pump and mounting surface. If you replace your sway bar links, use the bushings from the old ones.

 

and your 53 jets are too small, your going to need to be around 60,

that is after you get your new pump/ reg set up installed.

 

Ok. So installed the new pump. It was a carter 7psi pump. I Dnt have the numbeqg wit me. Now the car still chokes while driving but not like before. When i hit the gas, its ok but when i hit it, thats when it boggles and chokes. I Still have the 53 jets on and its a stock 12a. engine Never been broken apart. Theres no leaks of gas in the rear but the pump sounds like it have a vacuum leak lol. The part store told me they sound that way. My secondaries r still not opening. And now it started 2 smoke.

 

600cfm on a stock 12a is to big. It will never run perfect. You will need a 465cfm or similar.

 

I know its big. But i would like 2 get it running ok b4 i put it away 4 the winter.

 

the 7psi carder pump will need a regulator.

 

The guy at the parts store told me theres a built in reg. How much psi am i suppose 2 regulate?

 

i would guess between 4.5 and 6 like someone had said earlier thats a big carb for a stock 12a

 

I have my regulator set to 6psi

The fuel pump is regulated at 7psi

 

holley carb requires 6psi.

 

Every motor is different. The jets could be any where from mid 50's to lower 60's.

Holley's are built to run at 6psi, but I have seen best results on stock and small street ports closer to 4psi to 4.5psi.

 

The only way you are going to get your car right is look at a/f ratios. You car either put it on a dyno or get a wideband. I tuned mine on a dyno.