Teapot CFM?

[Grumpy Rick]

My '55 T-Bird came with an assortment of parts. Two teapot carbs and an Edelbrock 1406 600CFM (AFB copy)carb which was on the car along with the original distributor still being used.

I have installed a later 292 distributor, Pertronix with new coil, etc. and it is running fine now, except it is running too rich.

So, can anyone tell me what the CFM on the original teapot is?

I am deciding whether to take it to someone who can jet it properly, or change out the carb to a smaller one. I cannot see why this basically stock engine needs 600 CFM.

Can anyone more carb conscious than me suggest what needles and jetting would be a good baseline for my engine?

Advice requested and appreciated
.

Rick

PS: Should have mentioned...not a teapot fan. It will not be going back on the car.

[55blacktie]

The 55 Holley 4000 "Teapot" carburetor has an approximate cfm rating of 390. My two cents? The 600 cfm carburetor isn't necessary, but will work with rejetting. The Teapot, as it came installed from the factory, is not compatible with 57-up distributors that have both vacuum and centrifugal advance. However, the Teapot can be modified to work with the newer distributors. You'll find an article that tells you how to modify it at eatonbalancing.com.

Ted Eaton has said that you ca

[Grumpy Rick]

Wow, that was quick. I was guessing 400. Thanks for the info Blacktie. I have edited the post to mention I will not be using the teapot, but I will sure look into the info on Ted Eaton's site.

In a classic example of 'never get rid of anything', just weeks ago I gave away a small base Carter 4BBL carb that I saved for 60 years. I forgot that I was going to check it out for the Bird, and someone asked for it. I gave it to him along with two Quadrajets I will never use.

Thank you
Rick

[miker98038]

I ran a 1406 for years on my stock 292, then with a Paxton blower, and then moved the whole works to my 320 stroker. They’re really easy to change jets in, and even easier if it’s just the rods or springs. Do you have the manual or have you down loaded it?

[KULTULZ]

I am deciding whether to take it to someone who can jet it properly, or change out the carb to a smaller one. I cannot see why this basically stock engine needs 600 CFM.

Can anyone more carb conscious than me suggest what needles and jetting would be a good baseline for my engine?

You would need to go to the EDELBROCK SITE and enter you CARB NO. to see how the calibration was originally. Then tear it down and see if and how it has been modified.

- https://www.edelbrock.com/faq

- https://www.motortrend.com/how-to/re...ck-carburetor/

- https://www.amazon.com/edelbrock-tun...ock+tuning+kit

[Grumpy Rick]

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I just noticed there is oil leaking from my fuel pump. Could it be getting into the gas delivery? Just wondering if it is possible I may have oil in the fuel, causing it to look too rich?

I have black soot on the floor of the garage from the exhaust tips. Tomorrow morning I will go out and see if it is oily.

Probably grasping at straws here. I have just gotten the car on the road after 3 year hiatus.

PS: Another question. Any one know if those $20 adjustment kits for the carb are accurate, or should I only consider a genuine Edelbrock kit?

[KULTULZ]

Originally Posted by Grumpy Rick

I just noticed there is oil leaking from my fuel pump. Could it be getting into the gas delivery? Just wondering if it is possible I may have oil in the fuel, causing it to look too rich?

I have black soot on the floor of the garage from the exhaust tips. Tomorrow morning I will go out and see if it is oily.

Replace the pump mounting gasket. Sniff the oil dipstick to see it you smell gasoline. If the pump leaks fuel, it can go into the crankcase, not oil in the fuel supply.

The soot (CARBON) is from an overly rich fuel mixture.

PS: Another question. Any one know if those $20 adjustment kits for the carb are accurate, or should I only consider a genuine Edelbrock kit?

You buy CHI-COM, you get CHI-COM.

I would start with a QUALITY OVERHAUL KIT (setting the specs directly by CARB ID NO) and go from there. What you will find in the carb will scare you as a result of ethanol gasoline.

Check pricing on SUMMIT or JEGS. Don't trust AMAZON or FLEA BAY as there is a lot of counterfeit parts floating.

Is the car tagged? It needs to be taken out on the road and gagged.

[40 Deluxe]

[QUOTE=Grumpy Rick;2267808]My '55 T-Bird came with an assortment of parts. Two teapot carbs and an Edelbrock 1406 600CFM (AFB copy)carb which was on the car along with the original distributor still being used.


Since the Edelbrock has an air valve on the secondaries, your engine will never get 600 CFM if it doesn't need it. The secondaries only open enough to meet engine demand, so in normal highway driving they never open and only open partway even at full throttle (unless you have a high RPM race engine).
Get the Edelbrock manual and put the factory jets and metering rods back in if they have been changed. Check the float height and set to specs.
Use a tach to set the idle screws. Adjust one at a time to get maximum RPM (with closed throttle) then set idle speed to specs. Readjust mixture screws if needed. One at a time turn mixture screw in to drop about 20 RPM each. This will give lean best idle for both better fuel mileage and low emissions.
Forget any bogus vacuum gauge nonsense when setting idle mixture or timing!

[KULTULZ]

Forget any bogus vacuum gauge nonsense when setting idle mixture or timing!

Of course, that statement is IMO only, correct?

Tell me the difference between balancing with a TACH or VACUUM GAUGE.

How would you set BASE TIMING with a stretched chain w/o a vacuum gauge (other than static timing and that would be WAG)?

[55blacktie]

Good point.

[40 Deluxe]

Originally Posted by KULTULZ

Of course, that statement is IMO only, correct?

Tell me the difference between balancing with a TACH or VACUUM GAUGE.

How would you set BASE TIMING with a stretched chain w/o a vacuum gauge (other than static timing and that would be WAG)?

A tach is far more accurate. A vacuum gauge serves only as a rough estimate because the mixture screws can be adjusted a fair amount without the vacuum gauge needle moving, so you are likely to miss the lean best idle setting.
When it comes to timing you still set base (or static) timing by loosening the clamp and turning the distributor housing and using a timing light, no matter if the chain is stretched or not. This way the ignition timing is still correct even though the valve timing is retarded. Here again the vacuum gauge is only a rough estimate.

[KULTULZ]

When it comes to timing you still set base (or static) timing by loosening the clamp and turning the distributor housing and using a timing light, no matter if the chain is stretched or not. This way the ignition timing is still correct even though the valve timing is retarded.

OK. The DIST is driven off the camshaft, correct? If the chain is sloppy not only will the valve timing vary (float) but IGN timing also.

The first thing one does on a tune-up is to verify the balancer indexing. Then you check for chain stretch, especially on an older engine.

If you use just a TACH, yes it will do what you are describing, to a point. But when you get to a sweet point you then have to bring it back to proper curb idle all the while the mechanical advance is messing with you (if the mechanical curve is functioning properly).

Then you do it again.

It would be best (IMO) to use both (actually it would be best to use an exhaust analyzer) after verifying the cam drive.

An engine is just a glorified air pump.

[40 Deluxe]

[QUOTE=KULTULZ;2269256]OK. The DIST is driven off the camshaft, correct? If the chain is sloppy not only will the valve timing vary (float) but IGN timing also.

The first thing one does on a tune-up is to verify the balancer indexing. Then you check for chain stretch, especially on an older engine.

If you use just a TACH, yes it will do what you are describing, to a point. But when you get to a sweet point you then have to bring it back to proper curb idle all the while the mechanical advance is messing with you (if the mechanical curve is functioning properly). QUOTE]


It's been my experience that curb idle speed is below the RPM that mechanical advance kicks in so that is not an issue (unless the weights are hanging up or a spring is off).
If the timing chain is so badly worn that you can't get the ign. timing in tolerance, it's time for a new chain. If the balancer has slipped, it's time for a new balancer.

[55blacktie]

A couple of years ago, I read an article on testing several tachometers for accuracy. In a nutshell, some tachometers aren't very accurate.

[KULTULZ]

Originally Posted by 55blacktie

a couple of years ago, i read an article on testing several tachometers for accuracy. In a nutshell, some tachometers aren't very accurate.

- !!! Amen !!! -

[KULTULZ]

- READING A VACUUM GAUGE -

- https://www.motor.com/magazinepdfs/082001_05.pdf

It's been my experience that curb idle speed is below the RPM that mechanical advance kicks in so that is not an issue

If you are attempting to balance fuel mixture by RPM only, as the mixture balances the RPM will increase. Here come the CENTRIFUGAL ADVANCE a$$-u-ming the DIST is operating/calibrated correctly and/or the curve may have been modified). You then decrease RPM to CURB IDLE and start again.

In effect, you are chasing your tail.

To properly time/balance fuel trim on an engine it will require much more that a TACH.

Your procedure is fine on your car. But you should not convey to others (IMO) it's the only method that is available and is SURE-FIRE (pun intended).

[55blacktie]

Pinpoint accuracy, in any case, can be elusive. Even when putting it on a dyno, the engine will not necessarily perform as expected on the road. When you're happy with its performance, I guess you can say you found the sweet spot.

[Grumpy Rick]

Just posting to let anyone know I have been busy with other things lately, and have not gotten to the T-Bird problems yet.

I will be back as soon as I remove the carb and go through it. I can see it has at least some varnish build up in there. Kultulz' advice to start with the basics woke me up. The car sat for almost three years without being driven.

Thanks for all the help...Be back soon.

[KULTULZ]

Originally Posted by Grumpy Rick

Kultulz' advice to start with the basics woke me up.

... damn ... usually they cuss and throw things at me ...

... just weeks ago I gave away a small base Carter 4BBL carb that I saved for 60 years.

... again ...

The WCFB would have been a prefect replacement for the H4000. Even MERCURY realized that.

Now this is (IMO), but the only way I would have a H4000 is if the car had to be a nuts-on dedicated restoration.

And don't always go by the formulas that are given for CFM SIZING as those flow rates are done on a flow-bench for a perfect flow sizing. IMO (again), a 600 CFM is perfect for a street engine. You just have to calibrate it to the engine you are using it on (along with timing events).