Hey guys I have a couple questions. I recently tore the engine out and replaced the rear main seal, oil pan gasket, and replaced the stock intake manifold and 2bbl carb with an aluminum air gap intake and edelbrock 1405 600cfm carb. Also I dropped in a new distributor, coil, wires and new plugs. I've put the motor in tdc and set the distributor and everything but no matter how many times I set the distributor in I can't get the correct timing before the distributor hits the thermostat housing or the intake manifold. I'm mostly timing by ear but my buddy has a timing gun. But it still breaks up when you floor it no matter how many times I adjust the timing. Could the plug gap be too big? Also how can I get the timing right so the distributor doesn't hit the thermostat housing or the intake manifold?

 

you need to get that timing gun on it and see where you are before going any further.

it is possible to get the distributer off by one tooth and still get it to start, which may be what you have going on, but without putting a timing light on it, all you are doing is guessing.

get the timing set back to base with the timing light and report back. if it still runs like poop then the group can help you dig a little deeper.

 

Just went through this with my 292 V8. If you want to read the details search for "painless dizzy install" here at FTE.

Otherwise, you're one tooth off on your distributor. Fix that and you'll have the clearance on the body of the distributor.

 

What Meborder said.

 

Yeah, but a timing light won't install the dizzy in the right spot.

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I don't think it's the timing anymore guys. Maybe the carb jets are too large?

 

"I dropped in a new distributor ... no matter how many times I set the timing the distributor hits the manifold."

Sounds like you're off a tooth to me.

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The distributor either hit the thermostat or the temp sensor right behind the manifold. I pulled the temp sensor out for testing purposes and plugged the hole and found the sweet spot for timing and it still is studdering when you give it anymore than about 50% throttle. I'm thinking the jets are too big now.

 

and guessing won't tell him if it is right or not.

do you have a better suggestion?

"think" being the key word here.

you have two options, in assending order of dollars spent to correct it:
1. diagnosis the problem and fix accordingly
2. throw parts at it and see what sticks.

not trying to be harsh, but there is a systematic way to approach driveability problems.

I've used a stock 1406 on a stock 302 and i can tell you that the jets probably are too big, but it never caused a driveability problem before i changed the jets. it picked up a bunch of power and mileage once i got it dialed in, but you could stop the pedal from idle and the engine would never bog.

it's your truck, if you want to guess, it's no sweat off our back ... but if you could probably save a little time and money if you back up a step and start with known values.

i can't think of a single correctly installed distributor that would hit the water neck before it was timed correctly.

after you change the jets and it still doesn't run right, let me know what your base timing is so that we can help.

 

Alright alright you've proven your point. I'll put the gun on it today and see where it's at.

 

Ok so I set the initial timing to 6* and it was around 33* at 3000 rpm. The rotor at TDC points directly at #1. And it is still studdering when you give it more than half throttle or open up the secondaries. It's hesitating so much that it's not even letting it rev up

 

You are pulling and plugging the vacuum advance line to the carb when you time it, yes? And the vacuum advance can diaphragm is in good working order? Just because its "new" doesn't mean everything works right.

On the 1405 carb, the left side nipple is timed vacuum advance while the right side is manifold vacuum. Which one are you hooked up to? You've got the carb curb idle and mixture set close to "ball park" adjustments? I know, I know.....timing first, then carb but you have to be in the ball park to play.

6* initial and 33* @ 3000 RPM seems low to me. Should you not be about 36* - 38* at that (3K) RPM? Have you checked to see where your distributor "cams" are set?

 

Yes we pulled the vacuum advance and did all that. I haven't torn apart a diaphragm before so I don't know what to look for. The vacuum advance hose goes to the left nipple next to the Pcv hose. The screws on the front of the carb were adjusted while it was idling and they were turned in until the motor started bogging then turned out a turn and a half. And also I have no idea how to check distributor cams. I literally took the distributor out of the box and plugged it in.

 

To check if the vacuum advance can is working, apply some suction to the line - (take it off the carb, leave it on the distributor). If a change in RPM (higher) is noted, it's good.

As far as the distributor cams - there's numbers on them 10, 18 - varies, top and bottom - I can't remember at the moment the actual numbers. The number on the cam "in the slot" (sort of speak) is half the degrees of advance you have.

Example: If you have a 10 showing on the cam in use, you'll have 20* advance, 18* = 36*, when all in, etc. Could be a pain to change at the moment, and probably unnecessary....did the distributor come with and paper directions/particulars to the settings?

Just thinking aloud here.....

Edit: I know on the old distributors, one could adjust the vacuum advance by turning a small allen head wrench stuck in the vac advance nipple on the distributor. Don't know if that feature is available anymore.

 

It doesn't sound like timing is your main issue to me. Are you running a mechanical fuel pump and a fuel pressure regulator? The reasoning for my questions is, it doesn't sound like fuel delivery is right, whether it's getting too much or not enough. People often say you have to have a FPR when running an edlebrock and if you are running one, don't use a crappy spectre one.