Help with Edelbrock 1406 install

[jtinpdx]

Originally Posted by 68 P.O.S.

First of all, it’s not as easy as slapping the carb on there and cruising. Job number one is to verify the timing. If your timing isn’t correct right off the bat, nothing else will be correct either and you’ll be chasing your tail. That engine has vortec heads, so your timing number is 32 degrees total timing. That distributor has springs in it that allow the full advance of 32 degrees at 4000 rpm, which is too high for a daily driver. You want the full advance to fall between 2500-3000 rpm. Get the spring kit from Crane Cams and use 1 blue spring and 1 silver spring, and that will allow full advance at about ~2700 rpm. Everything else about that distributor is perfect for that engine, just take the blue cap off of the vacuum advance canister so it will function. Easiest way to set your total timing is to pull the springs out of the distributor (be careful, don’t lose ‘em) and just rev it to around 1500 rpm and set timing for 32 degrees. Without the springs, the weights will swing out fully at low rpm, so you won’t have to run it at 4000 rpm with your head under the hood lol. After the timing is advanced to 32 degrees total, put the springs back in and you can move on to the carb.

There’s 3 things you need to buy when installing an Edelbrock carb. First thing is either a fuel pressure regulator set to 5.5 psi or a fuel pump that produces 6 psi max. (like the Edelbrock fuel pump). Edelbrock carbs flood with any more fuel pressure than that. Also, adjust your float levels to the specs in the instructions, or they will make the carb flood as well. The floats are never set correctly out of the box due to shipping and handling. Secondly, you need a heat insulating gasket between the carb and intake, like the Edelbrock 9266. Edelbrock carbs are notorious for percolating fuel after engine shut down, which causes hard starting issues. A heat insulating gasket will cure that. Third, you need the Edelbrock 1487 calibration kit to properly select the best rods, jets, step-up springs, etc. for your engine.

Once the engine is timed correctly, pull the carb off and the transition slots need to be adjusted next. Here's a link to a great thread from Gregski that shows the transition slots: http://67-72chevytrucks.com/vboard/s...=713728&page=2. He begins to talk about it on post 37 and the following posts. The whole thread is worth a read, especially if you decide to go back to the Holley. After the slots are correctly adjusted, do not really use the idle adjustment screw anymore, as that will undo the work you just did. Slap the carb back on and set the idle mixture screws, with a vac gauge, for highest rpm. Ensure the vacuum advance and vacuum gauge are plugged into manifold vacuum when you do this. Turning the screws clockwise leans the mixture, turning counter clockwise richens it. Turn the screws all the way clockwise to bottomed out, then back out 1.5 turns, and start from there. Here’s a good video from Jegs outlining the setup: https://www.youtube.com/watch?v=wR_AfQjyT-A&t=3s.

As everyone else has pretty much said, and as shown by rharris’ picture, the back of the intake needs a connector with 2 or 3 ports on it to supply manifold vac. The trans modulator needs to be connected to that. The brake booster connects to the rear port on the carb (make sure the check valve at the booster is good and not leaking), PCV hose on the front large middle port routed to drivers side valve cover (not sure if it truly matters which side), cap the ported/timed port on the passenger side front because you have no need for it, vacuum advance plugs into the driver’s side port. Next, go for a ride!

This is why I love this site! Thank you for such a thoughtful and helpful reply. I've never tinkered with the innards of a carb before, but will give it a shot. I do believe the engine isn't timed right currently. I know how to time it generally but the shop that installed the engine marked the balancer in three places! So, I don't have 100% confidence which mark is TDC. That's my next step. If I can get that figured out, I'll start with timing it. I've been reading that initial timing of 4 degree BTDC is a good starting point. And I just ordered the Edelbrock gasket to block the heat. I'll let you know how things go.

[jtinpdx]

Originally Posted by 68 P.O.S.

First of all, it’s not as easy as slapping the carb on there and cruising. Job number one is to verify the timing. If your timing isn’t correct right off the bat, nothing else will be correct either and you’ll be chasing your tail. That engine has vortec heads, so your timing number is 32 degrees total timing. That distributor has springs in it that allow the full advance of 32 degrees at 4000 rpm, which is too high for a daily driver. You want the full advance to fall between 2500-3000 rpm. Get the spring kit from Crane Cams and use 1 blue spring and 1 silver spring, and that will allow full advance at about ~2700 rpm. Everything else about that distributor is perfect for that engine, just take the blue cap off of the vacuum advance canister so it will function. Easiest way to set your total timing is to pull the springs out of the distributor (be careful, don’t lose ‘em) and just rev it to around 1500 rpm and set timing for 32 degrees. Without the springs, the weights will swing out fully at low rpm, so you won’t have to run it at 4000 rpm with your head under the hood lol. After the timing is advanced to 32 degrees total, put the springs back in and you can move on to the carb.

There’s 3 things you need to buy when installing an Edelbrock carb. First thing is either a fuel pressure regulator set to 5.5 psi or a fuel pump that produces 6 psi max. (like the Edelbrock fuel pump). Edelbrock carbs flood with any more fuel pressure than that. Also, adjust your float levels to the specs in the instructions, or they will make the carb flood as well. The floats are never set correctly out of the box due to shipping and handling. Secondly, you need a heat insulating gasket between the carb and intake, like the Edelbrock 9266. Edelbrock carbs are notorious for percolating fuel after engine shut down, which causes hard starting issues. A heat insulating gasket will cure that. Third, you need the Edelbrock 1487 calibration kit to properly select the best rods, jets, step-up springs, etc. for your engine.

Once the engine is timed correctly, pull the carb off and the transition slots need to be adjusted next. Here's a link to a great thread from Gregski that shows the transition slots: http://67-72chevytrucks.com/vboard/s...=713728&page=2. He begins to talk about it on post 37 and the following posts. The whole thread is worth a read, especially if you decide to go back to the Holley. After the slots are correctly adjusted, do not really use the idle adjustment screw anymore, as that will undo the work you just did. Slap the carb back on and set the idle mixture screws, with a vac gauge, for highest rpm. Ensure the vacuum advance and vacuum gauge are plugged into manifold vacuum when you do this. Turning the screws clockwise leans the mixture, turning counter clockwise richens it. Turn the screws all the way clockwise to bottomed out, then back out 1.5 turns, and start from there. Here’s a good video from Jegs outlining the setup: https://www.youtube.com/watch?v=wR_AfQjyT-A&t=3s.

As everyone else has pretty much said, and as shown by rharris’ picture, the back of the intake needs a connector with 2 or 3 ports on it to supply manifold vac. The trans modulator needs to be connected to that. The brake booster connects to the rear port on the carb (make sure the check valve at the booster is good and not leaking), PCV hose on the front large middle port routed to drivers side valve cover (not sure if it truly matters which side), cap the ported/timed port on the passenger side front because you have no need for it, vacuum advance plugs into the driver’s side port. Next, go for a ride!

I did know about the 5.5 psi for the Edelbrock and I have a regulator and gauge in place, so I'm good on that front.

[jtinpdx]

Originally Posted by rharris

I used this on the manifold behind the carb. 3/8” npt, 3/8” barb and 1/4” barb for the power brakes and transmission line.

I got this in the mail and have installed it. I have the trans modulator and the brake booster running to it. I'll send new pics when I get a chance.

[jtinpdx]

Originally Posted by 68 P.O.S.

First of all, it’s not as easy as slapping the carb on there and cruising. Job number one is to verify the timing. If your timing isn’t correct right off the bat, nothing else will be correct either and you’ll be chasing your tail. That engine has vortec heads, so your timing number is 32 degrees total timing. That distributor has springs in it that allow the full advance of 32 degrees at 4000 rpm, which is too high for a daily driver. You want the full advance to fall between 2500-3000 rpm. Get the spring kit from Crane Cams and use 1 blue spring and 1 silver spring, and that will allow full advance at about ~2700 rpm. Everything else about that distributor is perfect for that engine, just take the blue cap off of the vacuum advance canister so it will function. Easiest way to set your total timing is to pull the springs out of the distributor (be careful, don’t lose ‘em) and just rev it to around 1500 rpm and set timing for 32 degrees. Without the springs, the weights will swing out fully at low rpm, so you won’t have to run it at 4000 rpm with your head under the hood lol. After the timing is advanced to 32 degrees total, put the springs back in and you can move on to the carb.

There’s 3 things you need to buy when installing an Edelbrock carb. First thing is either a fuel pressure regulator set to 5.5 psi or a fuel pump that produces 6 psi max. (like the Edelbrock fuel pump). Edelbrock carbs flood with any more fuel pressure than that. Also, adjust your float levels to the specs in the instructions, or they will make the carb flood as well. The floats are never set correctly out of the box due to shipping and handling. Secondly, you need a heat insulating gasket between the carb and intake, like the Edelbrock 9266. Edelbrock carbs are notorious for percolating fuel after engine shut down, which causes hard starting issues. A heat insulating gasket will cure that. Third, you need the Edelbrock 1487 calibration kit to properly select the best rods, jets, step-up springs, etc. for your engine.

Once the engine is timed correctly, pull the carb off and the transition slots need to be adjusted next. Here's a link to a great thread from Gregski that shows the transition slots: http://67-72chevytrucks.com/vboard/s...=713728&page=2. He begins to talk about it on post 37 and the following posts. The whole thread is worth a read, especially if you decide to go back to the Holley. After the slots are correctly adjusted, do not really use the idle adjustment screw anymore, as that will undo the work you just did. Slap the carb back on and set the idle mixture screws, with a vac gauge, for highest rpm. Ensure the vacuum advance and vacuum gauge are plugged into manifold vacuum when you do this. Turning the screws clockwise leans the mixture, turning counter clockwise richens it. Turn the screws all the way clockwise to bottomed out, then back out 1.5 turns, and start from there. Here’s a good video from Jegs outlining the setup: https://www.youtube.com/watch?v=wR_AfQjyT-A&t=3s.

As everyone else has pretty much said, and as shown by rharris’ picture, the back of the intake needs a connector with 2 or 3 ports on it to supply manifold vac. The trans modulator needs to be connected to that. The brake booster connects to the rear port on the carb (make sure the check valve at the booster is good and not leaking), PCV hose on the front large middle port routed to drivers side valve cover (not sure if it truly matters which side), cap the ported/timed port on the passenger side front because you have no need for it, vacuum advance plugs into the driver’s side port. Next, go for a ride!

Hey 68,
That link to the thread about transition slots isn't working for me. Mind sending the title of the thread and I'll search for it?

[geezer#99]

There’s a section in here about transition slots on a Holley. Same idea for all carbs.

http://www.crankshaftcoalition.com/w...EI_distributor

While the 9266 gasket is good, a heat spacer like this might be better.

https://www.amazon.ca/Edelbrock-8711...49839644&psc=1

[68 P.O.S.]

You're welcome, glad to help. Here, try this link for the transition slots: http://67-72chevytrucks.com/vboard/s...d.php?t=713728

The link geezer posted for the HEI is a great one too. Also a good read.

Is your intake a square bore or spread bore? Geezer may be right with his spacer recommendation; that will work better on a spread bore.

[jtinpdx]

Originally Posted by 68 P.O.S.

You're welcome, glad to help. Here, try this link for the transition slots: http://67-72chevytrucks.com/vboard/s...d.php?t=713728

The link geezer posted for the HEI is a great one too. Also a good read.

Is your intake a square bore or spread bore? Geezer may be right with his spacer recommendation; that will work better on a spread bore.

So, I have another issue here. I was heading in this direction - to put a heat spacer in there. I had one from Edelbrock, but it doesn't mate to the intake. It leaves a space. Check out the pics. The intake is a dual plane with a non-standard-oval shape. I took a look on Edelbrock for a heat spacer for this shape intake and didn't find one.

[68 P.O.S.]

That is a spread bore intake manifold. Original GM style for the Q-jet carbs. You're gonna need a spread bore to square bore adapter, like the Edelbrock 2696. I've never run one of these, so I don't know if the aluminum adapter will still transfer enough heat to the carb to make it percolate fuel. Hopefully someone can chime in on this. I'm hoping you won't need an adapter, plus the heat gasket. Will need longer carb studs too. How thick is the gasket in your pic, 1/2"?

[geezer#99]

You don’t need a spreadbore adaptor.
You need a sealing plate like this.

https://www.jegs.com/i/Edelbrock/350/2732/10002/-1

Then put your heat spacer on.

I wonder if your Holley problems was just a vacuum leak created by no sealing plate.

[jtinpdx]

Originally Posted by geezer#99

You don’t need a spreadbore adaptor.
You need a sealing plate like this.

https://www.jegs.com/i/Edelbrock/350/2732/10002/-1

Then put your heat spacer on.

I wonder if your Holley problems was just a vacuum leak created by no sealing plate.

Great thought, but nope. I think the carb with a regular gasket form a good seal. And also, I found the root cause with the Holley when I added the fuel pressure gauge. The fuel pump had blown and it was only pushing 1.5 psi.

[jtinpdx]

Guys,
For this 3 marks on the balancer issue. Does it make sense to assume that the first mark when spinning (closest to passenger side) is 0 degrees and the other marks are for the timing settings that the mechanic wanted? Also that first mark is painted as a straight line across the balancer and the others are dots on the outside.

Thanks,
Jeff

[68 P.O.S.]

It's going to be the one that goes across the balancer and lines up with the timing tab.

[68 P.O.S.]

Here's a little info on it https://www.crankshaftcoalition.com/..._TDC_lines_SBC

[jtinpdx]

Some good progress this weekend, but also another roadblock.

Installed the spacer plate and the wood spacer. That works great.

Also, sorted out the marks on the balancer and remarked - white line across at 0 degrees and a red mark at 32 degrees.

Then got stuck. When timing it, the timing marks are jumping all over the place. Can't get a read on it. Read about it and found that maybe there's an issue with the distributor? I replaced the plug wires in case it was that. Same issue. The distributor is new with the engine. About 5000 miles total.

Also, I was about to replace the springs in the distributor (1 blue / 1 white), but didn't figure out how to get the rotor off. I thought you just pulled that up. It didn't come off.

1 step forward, but no real progress in getting it running better.

[Dead Parrot]

Test the timing light on a 2nd vehicle to make sure the light isn't the source of the jumping flashes.

Rotor on a standard HEI should pull off after the two screws are removed.

Start it in the dark after your eyes have adjusted and look for sparks. 35,000 volts is always looking for a way to escape.

Probably a silly observation but the front nuts on the carb studs are missing.

[jtinpdx]

Originally Posted by Dead Parrot

Test the timing light on a 2nd vehicle to make sure the light isn't the source of the jumping flashes.

Rotor on a standard HEI should pull off after the two screws are removed.

Start it in the dark after your eyes have adjusted and look for sparks. 35,000 volts is always looking for a way to escape.

Probably a silly observation but the front nuts on the carb studs are missing.

Not silly at all. Definitely something I could've forgotten, but I took that pic mid project.

I'll try a couple of things this weekend. Another timing light, and also making sure the timing light sensor isn't too close to another plug wire. My suspicion is that that's the issue. I'll space the wires out and try again. Will let y'all know.

-Jeff

[jtinpdx]

Made a lot of progress today so thought I'd send an update.

I got the timing situation figured out. A different light worked and then the old light worked too. I might have had the sensor laying against a second plug wire. The I timed it based on suggestions here. Started with 4 degrees btdc as a starting point (vacuum line plugged). Then took the springs out of the distributor, unplugged the vacuum line, and set at 32 degress at 2000 rpm. Runs much better.

Then I put in the Crane Cams springs. I chose 2600 rpm to be in all in at 32 degrees. Funny thing about the kit. You guys on here said blue spring and white spring. Directions say blue spring and yellow spring. And the package includes silver, copper, and black springs. No blue, white or yellow. But easy to figure out which was which. One heavy, one light.

Then I started on the carb. Just the idle speed and idle mixture screws for today. Might fine tune those tomorrow and tinker with the innards tomorrow.

See below for some pics of everything all the way back to the trans and brake vacuum lines. And breather and PVC swap.

Thanks again for all the help on here. I appreciate it a great deal.

-Jeff

[jtinpdx]

Originally Posted by Dead Parrot

If you are planning on using a OEM type cleaner cover, it might interfere with the fuel inlet. Mine did. Fix was switching to a banjo fuel inlet.

Yep, have the banjo and a gauge on it. Still a tight fit but works. Pic later in the thread. Thanks!

-Jeff