3814 Carb Tuning Issue

[John H.]

Re: if you have never removed a gas loaded

Mark -

You indicated that the timing was set at 4* AFTER TDC, which was the original factory setting for a 300hp Powerglide with K-19, and you increased it to 10*; is the 10* AFTER or BEFORE TDC? The factory 4* AFTER TDC was a temporary aberration to satisfy the A.I.R. system function and California, and the car will run a LOT better with the initial timing set at 6*-8* BEFORE TDC, the same as the non-A.I.R. cars.

The 1967 Chassis Overhaul Manual has a complete step-by-step photo-illustrated section on rebuilding the 3810/3814, including all the adjustments, and the float level specs are in the back, in the Specifications section.

[John H.]

Re: if you have never removed a gas... ADDENDUM

Mark -

I should have added in my previous post that your distributor will need some work if you set the initial timing to the non-A.I.R. spec (6* BEFORE TDC); the K-19 Powerglide distributor had 40* of centrifugal advance (which gave 36* total timing with the 4* AFTER TDC initial timing setting), and the non-A.I.R. distributors had 30* centrifugal advance, which also gave 36* total timing with the 6* BEFORE TDC initial timing setting. Using the non-A.I.R. 6* BTDC initial timing setting with your distributor (assuming it's original to the car) will produce total timing of 46*, which will detonate like a coffee can full of ball bearings.

[Mark P.]

Re: 3814 Carb Tuning Issue--Success?

Joe Jerry & others who have commented

First of all, based on Jerry's advice, I opened up the float and discovered the float was contacting the metering plate and this explains why sometimes the carb caused fuel to run out of the secondaries and at other times the car ran too lean. The car has never run so good in the 9 months that I have owned it.

I have yet to go back and reset the timing (it is still 10 degrees "After"). Unfortunately, I work overseas and will not be back for several weeks.

I have previously contacted all the previous owners and they all claim the engine is original minus the K19, but I am not sure how to verify that the distributor is original and set up for the K19.

Assuming that the distributor is original and I reset the timing back to factory specs at 4 degrees "After". What is the downside?

Thanks---Mark

[John H.]

Re: 3814 Carb Tuning Issue--Success?

Mark -

The downside of setting it back to 4* AFTER TDC is sluggish performance, poor idle cooling, and reduced fuel economy. Those were the hallmarks of K-19, but it made California happy. All your car needs to really pep it up (and get rid of the downsides) is to have the distributor re-curved so it only provides about 28*-30* centrifugal advance (same as the non-K19 distributor), set the initial timing at 6* BEFORE TDC, and make sure the vacuum advance is working and is connected to a full manifold vacuum source. You won't believe it's the same car.

[Clem Z.]

i have never seen the float rubbing on the

metering plate problem. the float arm would have to be bent or someone used a too thick aftermarket metering plate gasket instead the the thin holley ones. a rubbing problem on the metering plate can occur if you try to use a brass float instead if the nitrophyl on center hung float bowl carbs that use the metering plate instead of a metering body. the arm on the nitrophyl float is shorter than on the brass one that is why the nitrophyl floats are used in the end carbs on the 3 X 2 carb setup

[Mark P.]

Re: i have never seen the float rubbing on the

Clem

I hired a vendor to rebuild the carb. He used a brass float during the rebuild.

Mark