Carburetor wizard part 2

[furious70]

How much mechanical timing do you have when it's all in?

 

[Cheapsunglasses]

I would go back to the 68/57 rod, and change to one size bigger on secondary jet. That chart that was posted about the ratios should be helpful.

you can calculate surface area of a given jet and rod combo, but as close as you are that’s what I’d do. I think your numbers look good other than wot. 12.5-13 would be nice at wot, but just see where it goes with one step.

from there you can play with air door, springs, and pump shot. Check for vacuum leaks as the one guy posted. Toss in some new plugs of the proper heat range and you’ve got this.

This is the 3rd set of plugs I’ve had, every plug combination someone says is wrong. Plugs aren’t cheap, and kind of a pia to change.

 

[Cheapsunglasses]

How much mechanical timing do you have when it's all in?

My distributor is a Mallory mechanical advance dual point, I believe I’m all in around 32 degrees, at 2200rpm

 

[Cheapsunglasses]

I’m kinda wondering how much more carb tuning my neighbors will put up with

 

[Some Car Guy]

This is the 3rd set of plugs I’ve had, every plug combination someone says is wrong. Plugs aren’t cheap, and kind of a pia to change.

Problem is they look fouled. You could clean them off and hope for the best. The tune has been way off and it’s a reality that you need to do something with them. Rockauto has always been the cheapest option for me. I run ngk iridium in my 440. I would stick with the heat range 440 source says and that will keep you out of trouble.

what is your initial and total timing number?

 

[Cheapsunglasses]

10 degrees btdc, and 30 something. So total would be 40 something

 

[Ceedawg]

This is the 3rd set of plugs I’ve had, every plug combination someone says is wrong. Plugs aren’t cheap, and kind of a pia to change.

Soak them in acetone for awhile then lay one at a time on a non flammable surface, light em up with a small solder torch. Certain carb cleaners work too (the type with the bad stuff in it) nothing wrong with those plugs just dirty!

 

[Geoff 2]

Cheap,
The T slot position is perfect!

 

[Geoff 2]

Cheap,
You are also getting bad advice...again. The pic of your T slot is perfect, just the right amount below the blades. That leaves plenty of T slot left for transition onto the main cct.

Idle speed. It is what it is. The idle speed should be what THIS engine will comfortably idle at. Factory idle speed is 500. If this engine is not happy at 500, but idles smoother at 750, leave it there. Internal wear, worn cam lobes, etc could make the engine want to idle at a higher speed. You do not force it down to some arbitrary number. There is a reason that engines with long duration cams might need to idle at 1100 & they would most likely stall if they were forced to idle at 500.

Spark plugs. NGK heat range 5, no colder. Not sure about the ALs you are using.

You could also benefit from a HEI type Elec ign system. The only benefit your dual pt dist has over single point is at higher rpms from the extended dwell.

 

[Some Car Guy]

10 degrees btdc, and 30 something. So total would be 40 something

That doesn’t sound right. Total is initial plus whatever is in the distributor. Factory heads make the best power at 33-35 degrees per Eberg in mopar action this summer. I had settled on 34 after finding my car ran best with that. The chambers on the Source heads should be better and might want a different number. 40 would be pretty high.

initial can be whatever you find it likes, just recurve so the total stays where it needs to be.

I read some of the old thread you had. If you’ve had total at 40+ with factory iron heads, that’s why it was pinging. The aluminum heads would help with that, but I would still expect some trouble.

 

[Some Car Guy]

Rev it up to something like 3000, read the timing. That will be the total number. Then reset it to the 33-35 range. That will get it in a safe zone. Then check timing at idle with the vac advanced plugged. That will show initial setting and will give us the advance curve built in your distributor.

then you can recurve it so everything will be at a good number. I see a post where you are saying it has 32 degrees. If that’s the case it’s not been set up with a performance curve. I’d be surprised an aftermarket distributor came with that curve. No telling what has been done to it along the way though.

 

[Cheapsunglasses]

Here’s an update, I advanced the ignition a little, then I drove it to a friends place, 30 miles on the interstate, 80mph and 2500rpm or so. With the 68/52 rod, and 101 jet, with the orange springs. My AFR was all over the 13s and even kind of into the 14s and 15s.

 

[Bee1971]

T Slots - Idle circuit

Jetting - Metering - Springs

Spark plug color looked terrible as stated earlier

Still haven’t figured out correct timing specs and done a compression check on a stock bottom end

 

[Cheapsunglasses]

T Slots - Idle circuit

Jetting - Metering - Springs

Spark plug color looked terrible as stated

Still haven’t figured out correct timing specs and done a compression check on a stock bottom end

But yet all you want to discuss is six pages of AFRs on probably an over carbureted low compression motor

You’re the first person to say it’s an over carbureted engine, nobody else has said that. Why are you the first person after 6 pages to say this?

I’ve also moved around the timing, but I guess you skipped over that.

 

[Bee1971]

Read post #103 then #106

That doesn’t tell anyone anything

 

[Bee1971]

Let’s see all eight spark plugs after your 30 mile CRUISE Circuit

Then do a compression check on all eight while they are out

Let’s start there

 

[Cheapsunglasses]

I’m trying to make small changes, I’m not going to just completely rebuild an engine because my carb isn’t tuned properly.

 

[Cheapsunglasses]

Just like some people don’t use an AFR gauge, I don’t use a timing light. #1 at tdc, drop the distributor in, read a vacuum gauge, read an afr gauge, listen to the engine, it’ll tell you what you want.

 

[Bee1971]

I didn’t ask you to rebuild your engine

Thanx

 

[Cheapsunglasses]

I didn’t ask you to rebuild your engine

Thanx

Go bother someone else on another thread, you’re not helping here.

Probably my fault because I didn’t use the right words, I’ll edit today’s post.