hey everyone ive been having a few problems with a carb swap. first problem i had was well noobie mistake with carbs. hooked the fuel return to the main vacuum on the carb..... whoops. fixed. next problem ****** fuel pressure regulator. working on it. and the third. keeping it running. it was having a problem with major flooding. but i thought with a 2 barrel i wouldve been running a bit lean. could be a problem of the fuel pressure. but i did have it running when i had some help from a friend a bit more experienced with carbs. i beleive he adjusted the idle aswell as the air fuel ratio. and i havent touched that since. but when he left and i went to go put the throttle and transmission kickdon cables and return spring on. i couldnt get it to start again.

im currently running a 2 barrel rochester carb. computer has been removed. wiring for computer and fuel injection removed. new 0.015" head gaskets on 624 heads gasket matched and ported. mild cam. new valves. 9:1 flat top pistons. bored 0.030" over forged rods.

im looking for any advice on what i should be doing other than the fuel pressure regulator. my question is am i running too small of a carb for this motor now? the 2 barrel was rebuilt jetted and ported with a new butterfly put in by the person who helped me tune the car when we had it running.

 

Year model helps??????

Flooding has nothing to do with carb size.
You either have too much pressure at the carb over powering the needles or the float needles are sticking.
What reg did you use ? How is it plumbed ?

 

1984 corvette originally with the crossfire injection. FROM THE BEGINNING. the corvette started smoking and was a DD for my father as his summer car. he wanted to replace the engine instead of having anything diagnosed. and ordered an engine with vortec heads BUT wanted to keep the crossfire. so we realized the crossfire wouldnt bolt to the vortec heads and swapped them back to the original 624 heads. from there we got the car running and found out the valve seals were gone. so we ripped the motor apart. and convinced him to switch to a carb. we picked up the intake manifold and carb from a friend for nothing and got the other to rebuild it for us. port matched the intake and heads. ceramic coated the headers and intake aswell as the heads to help keep the heat down. we also replaced and re seated the valves aswell as put new seals in and a high compression head gasket. once i get the motor running again ill talk to you about the water pump or possible head gasket sealing issue *sigh*

also its a 0-140 psi which is way to high to even try and get it under 10psi just the only thing i had around i could use to regulate the pressure down from the 15 psi inline pump. also the fuel pump was removed in the tank and a hose added to extend the line.

 

Still haven't noted how you converted the fuel system from injection to carb (relating to your current flooding problem ? )

 

put that in the last edit. sorry about that. i used the original fuel line in the engine blocked the return line after i realized there was no return on the rochester. or well any carb that i know of now. the intake and 2 barrel rochester were given to us. the carb was rebuilt with new seals. new jets. the floats and bowls cleaned. and when the person who rebuilt it was here helping me diagnose the car he had it running enough to tune it for the idle and air fuel. so i went to get a throttle return spring came home and went to start it for a glorified burnout and it was flooded. so i left it for about a week and had it running briefly but ran out of gas. so ive come here for some opinions and was going to get some gas tomorrow on payday lol

 

Sounds like you need the correct carb reg to get the pressure down to the recommended level
Read
http://www.jalopyjournal.com/forum/s...0&postcount=12

 

sweet. going to try it out tomorrow hopefully either that or over the weekend. ill be back ! thanks for the help

 

carb fuel pressure is very ,very low , like under 8 pounds or so. you may be forcing it to flood with high pressure. Any cam with more than 450 lift will destroy stock vortec valve seals as soon as its run. Many running vortecs use beehive springs to get past that problem cheaply. I suppose you could put a tee with one end going to a fuel pressure reg. back to the tank (return)

 

No need
Just deadhead the pump through a non bypass reg like the popular Holley # 12-803

 

Is this thread for real?

 

did the vortec heads end up back on the motor ? I am not sure.

 

yes it is for real. budget build my friends. the 624 76cc heads with crappy castings are on the motor. the heads were thoroughly checked to make sure there were no cracks or anything like that. everything was ceramic coated for looks really. not much was used and it just helped make the engine looks a bit better than it did. and helps with surface rust

 

got a new carb on there with good seats gaskets needles etc. etc? what are you using for a fuel filter? in tank or out of tank pump?

 

A two barrel?? You thinking of using twin 2 barrels, right?

Have you checked hood clearance? The lowest 4 barrel intake is marginal. Not sure what height the Two Barrels are.. but before you go much further this needs to be done.


If your using anything like a stock in tank pump FI [not clear on that] a bypass regulator is what you will need. 6 -7 PSI is more rational a pressure.

Setting the bowl floats is critical. Need the Carb. info there.
Jets will likely be two big as well.

Air cleaners?? The air under a C4 is death to performance!!! Getting outside air is just about essential.

TJM

 

Read above .
Way too much pressure

 

any1 know how much it would cost for parts to do a crossfire to carb swap? I'm interested in this. My 84 is pretty much stock under the hood.

 

Go on craigslist in your area and look for a qjet carb and intake off a sbc. Then look for an pre 81 sbc or Bbc gm hei distributor. You could probably get these items from a junk yard too ..Also get the throttle bracket off most any car that had a sbc with a qjet and auto trans. $100-$200 plus you will need a return style fuel pressure regulator. A used edel. Performer intake and 600 carb $150-250.

 

Sounds like you need this part.

http://www.summitracing.com/parts/hl...03bp/overview/

This will drop your fuel pressure, and let the extra fuel and pressure get back to the tank. You need this no matter what Carb you run.

What distributer are you running? You need an Hei, or small cap with remote coil.