Hey guys,

This isn't about my camaro but i'm sure you guys could definitely give me some input.

We are working on 55 bel-air with a 70 corvette 350. Specs on the engine:
-10.5:1 pistons
-Offenhauser(however u spell it) 360 intake
-comp cams hydraulic magnum .501 lift cam w/ matching valve springs, lifters & chain
-heads ported, milled for valve springs, .196 intake i believe
-summit roller rockers
-hooker super comp headers
-hei distributor bought off ebay
-1406 edelbrock carb 600cfm
-accel shorty plugs
-true dual exhaust

We have 2 serious problems:
1. Starves itself of fuel after running for about 15 minutes at idle.
2. Throws raw gas out the exhaust and the plugs seem very wet.

1. We have an in-line fuel pressure gauge hooked up right b4 the carb along with a clear fuel filter to monitor the fuel coming from the mechanical pump. After about 15 minutes of running it starves itself and does not want to run. It is even worse when driving. The car has no power and does nothing but stumble and bogs.

We thought the gas might be boiling and put some dynamat on some areas close to the headers, but it is obvious there is no boiling.
Does this sound like a fuel pump issue?

2. Since we hav a high lift cam, we dejetted and lowered the metering rods 12% to account for the wet plugs. The plugs are still wet black and the exhaust smells of pure gas. Our next thought was that oil is blowing past the rings but this doesn't make any sense because before the cam swap, it was super clean and didn't take any oil. We replaced one of the valve seals which seemed to have come loose but this did not change the amount of smoke coming out of the one bank's exhaust. Any ideas..hotter plugs, msd ignition box? pull the engine and replace the rings..haha?

With the combination of these two problems, me and my father r going nutty..

 

Team camaro

How much fuel pressure are running??? Carb systems like between 4-6PSI. anything greater will result in flooding. Also, check your carb float level and base timing. There is a remote possibility that your timing might be 180* degrees out, just double check and make sure that cyl 1 is on compression stroke when dizzy fires #1 cyl.

//RF

 

how about a sunken float?

 

whats your timing set at?
whats the specs on the distributor?
fuel pump?

second i'd toss those accell plugs in favor of good 'ol ac delcos. don't need shorties if u use a 5/8ths ofset wrench. regardless of what you want to run new plugs are in order.

I hated my edelbrock, floats are a pain to adjust as well. def check those as Spit suggested and get back with us.

 

Sounds like the fuel pickup in the gas tank is full of the crusties and the funk of 10,000 ages, like old cars that have sat around alot most always are.

Drop the tank, pull the sending unit, rod it out.

You may need to replace the fuel line running from the tank to the engine as well, for the same reason.

I'd suggest sticking a decent carb on it, and see if that makes any difference..... AFTER you get the fuel delivery problem worked out. You sure don't want to load up yet another carb with whatever substance it is that's coming out of that tank.

Also, there may be a clue hereTry a different dist. Again, AFTER the fuel delivery/contamination problem is sorted out. That's gotta come first.

 

Replace the spark plugs with new ones. Remove the distributor cap and rotor. Remove the advance weights and springs. Stick them in your tool box. Using two electrical tie wraps bind the advance mechanism fully advanced so that the timing is locked out and cannot move. Orient the tie wraps with the knot down so the rotor will go back on. Reinstall the rotor and cap. Start the motor and set the timing to 36deg BTDC at idle with vac adv disconnected. After its set, reconnect the vac adv to ported vacuum.
Let the motor warm up and reset the idle speed to 850rpm and reset the idle mixture screws for best idle quality. Forgot to mention, replace the stock out of the box jetting and metering rods in the carb along with a light tension step up springs so that the rods stay down (lean) at idle. (3.5" or 4.5" rated) step up springs. Make sure the PCV valve is hooked up to the carb base vac port and functional.
The comp cams 292H (501" lift) Magnum camshaft needs full advance at idle in order to idle correctly. (36deg BTDC at idle) Other wise the carbs throttles end up too far open at idle and the fuel does not burn quick enough causing the gas in the exhaust.
Once you've corrected the advance and reset the carb 99% of the fuel in the exhaust will be gone. The motor will now have very good throttle response.
If your motor is hard to start when its hot (slow starter motor speed) with the ignition timing locked out at 36deg, install a simple ignition power interupt switch on the dash to allow you to kill the spark while cranking over the starter. Crank it over with the spark kill switch off, (no spark power) then throw the switch and it will fire easily.

The 292H magnum cam requires a loose "3500stall" torque converter (10") for a auto trans.

 

thanks for the quick replies guys, im gonna give ur suggestions a shot 2night. to clear up some questions:

trans is a muncie 4 on the floor w/ 3.70 rear.

fuel pressure runs at 5lbs until it starves itself. the tank was just replaced 3 weeks ago with a new danchuck gas tank along with sending unit. also put in a new mechanical fuel pump along with the tank.

the carb is new, just bought it 2 weeks ago and we checked the floats and they seemed to be in the proper location, i think the manual says 7/8"? dont hold me to it but i kno it matched whatever the manual stated. i think right now we are also using 1 spring lighter than the stock step up spring. the jets and metering rods were leaned 12% in cruising and power. there is no emissions on this engine, so we're not running with a pcv valve. another problem we were having was that the air/fuel screws weren't even changing the idle and that worried us because obviously its still dumpin too much. so peculiar considering this is a 600 carb..

i agree that the distributor may b a problem because it was a cheapy bought new off of ebay, but to save a few bucks we went with that(i kno what ur thinking, i was thinkin the same thing when i hit 'buy now'). i think right now we hav timing set to 34* total advance.

i will def be changing the plugs 2night as well since those were the new plugs used for break in of cam. i agree that they should be changed.

thanks again, ill keep u guys posted after 2night!

 

So it runs super rich, putting out raw exhaust, and then the fuel pressure suddenly cuts out and it dies?

 

This is what I'm trying to tell ya. Just about everything you did to "dial it in" was in the wrong direction. When you get the distributor timing right the carb throttle blades closed back up at idle the idle mix screws will be responsive to adjustment. Put the stock jetting back in. Fix the distributor advance as outlined above and reset the carb. Hook up the PCV to the carb base. Make sure the other valve cover is vented. It is part of the carb calibration design. If you run without it the carb will always idle rich.
Check to see that the fuel tank is vented or a vacuum will build up in the tank after a while stopping all fuel flow to the carb.