Edelbrock 1409 tuning

[406Maverick]

Hello everyone! I have finally had a chance to get the boat out on the water a few times this spring, and so far she has been running like a champ- almost. The only issue is a short "bog" anytime I go WOT. Doesn't matter if it's from a standstill or if I'm cruising. If I go WOT it bogs for maybe .5-1 second and then takes off. Here is how I have it set up now-

01 VP 5.0
Edelbrock 1409- all stock carb tuning (as it came in the box)
Timing @ 10 degrees base
Accelerator pump set to top hole (richest)
91 octane ethanol free fuel


I have thought about trying the upgrade the accelerator pump spring, but I am not sure which one would be stiffer- maybe a 1468..? Is it possible I should leaner on the accelerator pump? thanks!

 

[stouchton]

yup - 1468 pump will give you a bigger and longer pump shot. Step 1 to eliminate bog.

Also - if it has vacuum secondary and you can tighten the spring to delay opening this can help. I normally tighten them to delay them to eliminate bog, then loosen and try them again until the bog shows up - then of course tighten up slightly. Hope that makes sense...

 

[Scott06]

Hello everyone! I have finally had a chance to get the boat out on the water a few times this spring, and so far she has been running like a champ- almost. The only issue is a short "bog" anytime I go WOT. Doesn't matter if it's from a standstill or if I'm cruising. If I go WOT it bogs for maybe .5-1 second and then takes off. Here is how I have it set up now-

01 VP 5.0
Edelbrock 1409- all stock carb tuning (as it came in the box)
Timing @ 10 degrees base
Accelerator pump set to top hole (richest)
91 octane ethanol free fuel


I have thought about trying the upgrade the accelerator pump spring, but I am not sure which one would be stiffer- maybe a 1468..? Is it possible I should leaner on the accelerator pump? thanks!

You can try leaner and see if that makes it worse . Edlebrock makes a kit with 3 different accelerator pump nozzles. That may be what u need . That cured my bog on my 5.0 with a 1409

 

[406Maverick]

I had a major bog at 3000 rpm - at WOT it would immediately rev up to 3000 and then bog down to about 2700 and stay there struggling to get up on plane.. once up on plane it would rev up to max rpms no problem. I started with upgrading the accelerator pump to the 1468 and left everything else stock. This greatly improved throttle response however it did not eliminate the bog at 2700-3000.. I talked to edelbrock and they recommended going 4% richer with cruise and power mode. New .101 primaries and .070x .047 rods. I also changed the step up springs from the stock orange to the pink ones. This greatly the improved the 2700-3000 bog (though still slightly there) however past about 3200 I have to gradually increase throttle to get to max rpms otherwise it stumbles and wont accelerate. I'm thinking next I should richen the secondary but not quite sure yet.. any thoughts?

 

[Scott06]

I had a major bog at 3000 rpm - at WOT it would immediately rev up to 3000 and then bog down to about 2700 and stay there struggling to get up on plane.. once up on plane it would rev up to max rpms no problem. I started with upgrading the accelerator pump to the 1468 and left everything else stock. This greatly improved throttle response however it did not eliminate the bog at 2700-3000.. I talked to edelbrock and they recommended going 4% richer with cruise and power mode. New .101 primaries and .070x .047 rods. I also changed the step up springs from the stock orange to the pink ones. This greatly the improved the 2700-3000 bog (though still slightly there) however past about 3200 I have to gradually increase throttle to get to max rpms otherwise it stumbles and wont accelerate. I'm thinking next I should richen the secondary but not quite sure yet.. any thoughts?

What do your plugs look like ? I actually got rid of a couple of bogs i had maybe around 3400 and 3800 By going leaner. you may want to try going back to the stock springs and see what that does.
as far as secondaries run 5-10 min at WOT or close to it stop real quick and yank a couple plugs i would check that before Swapping secondary jets. I tried going one step richer on secondaries and it was too much.
here is a good plug reading article

Wallace Racing - Spark Plug Reading

eventually i want to stab my fuel air ratio meter between the manifold and the elbow.… the little bit ive used it on one of my carbureted cars it gives a wealth of info

 

[406Maverick]

What do your plugs look like ? I actually got rid of a couple of bogs i had maybe around 3400 and 3800 By going leaner. you may want to try going back to the stock springs and see what that does.
as far as secondaries run 5-10 min at WOT or close to it stop real quick and yank a couple plugs i would check that before Swapping secondary jets. I tried going one step richer on secondaries and it was too much.
here is a good plug reading article

Wallace Racing - Spark Plug Reading

eventually i want to stab my fuel air ratio meter between the manifold and the elbow.… the little bit ive used it on one of my carbureted cars it gives a wealth of info

Haven't pulled the plugs after a hard run yet- that's next on the list.. I did try putting the stock orange springs back in and couldn't tell much of a difference from the pink ones.. have a steady 5.2-5.5 fuel psi at WOT as well..

 

[Scott06]

Haven't pulled the plugs after a hard run yet- that's next on the list.. I did try putting the stock orange springs back in and couldn't tell much of a difference from the pink ones.. have a steady 5.2-5.5 fuel psi at WOT as well..

check the plugs first that should drive your next steps int terms of rich or lean primaries or secondary jets...

If the springs didnt make a diff try one the other way lighter spring to make it stay lean a little longer.

In the end I found on my 5.0 the 1409 was pretty much except for accelrator pump nozzle ok right out of the box.

 

[406Maverick]

check the plugs first that should drive your next steps int terms of rich or lean primaries or secondary jets...

If the springs didnt make a diff try one the other way lighter spring to make it stay lean a little longer.

In the end I found on my 5.0 the 1409 was pretty much except for accelrator pump nozzle ok right out of the box.

Good to know! I think I may go out and put the stock jets and rods back in, and mess with springs since I can easily change out springs while on the water.. It's tough getting a boat dialed in when the closest water is an hour away..

 

[406Maverick]

I'm also starting to wonder if this may be an ignition coil issue- just starting to research that possibility..

 

[Scott06]

I'm also starting to wonder if this may be an ignition coil issue- just starting to research that possibility..

Ohm the primary and secondary side of the coil before replacing

 

[406Maverick]

OK so today was a good day! Made some headway I think. I think I figured out the root cause of the 2700-3000 rpm bog. So I had 2 fuel pressure gauges- one electric and 1 liquid filled tee'd off of my pressure regulator. I decided to get rid of the liquid filled and just go with the 1 electric one. Well it appears the piping and tee's etc made my fuel pressure read high. So now I have the fuel pressure right off the regulator. When I 1st changed it out my pressure was only 2.5-3... so now I am back where I need to be. So my current tuning is as follows-

Stock jets
Pink step up springs
1468 accelerator pump on richest hole

I took er out today and it is MUCH better.. gets right up on plane. I was able to do a WOT run and pulled the #1 and #5 plugs. They look lean to me.. brand new NGK Tr5 gapped at .045... what do you all think?

 

[406Maverick]

 

[406Maverick]

 

[406Maverick]

 

[Scott06]

Ive been using this plug reading guide http://wallaceracing.com/plug-reading-lm.html note the full base ring of color indicating rich/lean and heat range ring per the article .

per that i think you are ok whee you’re at. When i installed my 1409 six years ago i had plugs identical to yours thought it was too white… went one step richer on the metering rods and later backed that out because i was getting black plugs and a stumble similar to what you were getting

 

[406Maverick]

Gotcha, thanks for the input! So here's something else I am wondering. My boat was originally a Gi that I converted to a carb. The Gi calls for a .045 spark plug gap and the GL calls for a .035.. which one should I follow?

 

[Scott06]

Gotcha, thanks for the input! So here's something else I am wondering. My boat was originally a Gi that I converted to a carb. The Gi calls for a .045 spark plug gap and the GL calls for a .035.. which one should I follow?

.045 thats what I run on my mercruiser with same heads and plugs. Thats what you ran these tests at and seems to be working right? I honestly dont think you'd see a difference between .035 and .045 gap in this setting anyways....

 

[saf]

Hello everyone! I have finally had a chance to get the boat out on the water a few times this spring, and so far she has been running like a champ- almost. The only issue is a short "bog" anytime I go WOT. Doesn't matter if it's from a standstill or if I'm cruising. If I go WOT it bogs for maybe .5-1 second and then takes off. Here is how I have it set up now-

01 VP 5.0
Edelbrock 1409- all stock carb tuning (as it came in the box)
Timing @ 10 degrees base
Accelerator pump set to top hole (richest)
91 octane ethanol free fuel


I have thought about trying the upgrade the accelerator pump spring, but I am not sure which one would be stiffer- maybe a 1468..? Is it possible I should leaner on the accelerator pump? thanks!

I've been playing with my Edelbrock 1409 for past couple of seasons (I have 97 5.7 GI converted to carb). My accelerator pump is set to minimum. Tried changing it around and did not see any difference. I am not an expert by any means, but your problem feels more like a metering rod problem to me. I'd try going to richer rods/spring combo. You can get a tuning kit for 1409 relatively cheap, changing rods/springs is a breeze.

 

[ddbyrd3]

I run a 1409 on a 305 GL-B and on a 1992 Chap with a 572A 350 VP.

My 2003 305, after adding a 1" phenolic spacer to eliminate heat transfer to the carb, I was lean before the spacer. Now I am back to stock settings with the orange spring, AC pump on leanest setting and she runs great. Although I rum 91 octane and added 2 degrees of timing. That in and if itself woke her up. On my 1992 572A 350, I also added a 1" phenolic spacer, and had to go 4% richer per the Edelbrock manual. Stock timing setting, and she runs hard!! No flat spots, or bogging at any throttle position.

 

[Scott06]

I run a 1409 on a 305 GL-B and on a 1992 Chap with a 572A 350 VP.

My 2003 305, after adding a 1" phenolic spacer to eliminate heat transfer to the carb, I was lean before the spacer. Now I am back to stock settings with the orange spring, AC pump on leanest setting and she runs great. Although I rum 91 octane and added 2 degrees of timing. That in and if itself woke her up. On my 1992 572A 350, I also added a 1" phenolic spacer, and had to go 4% richer per the Edelbrock manual. Stock timing setting, and she runs hard!! No flat spots, or bogging at any throttle position.

Interesting so you think the spacer made it go richer? I just put a 1/2" phenolic spacer under mine for same reason, didnty help hot restarts (open throttle seems to ) and now my plugs look fouled a bit. ...