I have a rebuilt 327 with a crane 350 horse cam just put on an offenhouser four deuce intake along with four brand new Holley 94 carbs. I turned the screws in and back out about 3/4 turns but the engine still seems to be running extremely rich. I have a fuel pressure regulator and it is turned down to about two and a half pounds. Does anyone have any idea what the initial settings would be on this setup? Also would I change the ignition timing any with this setup or leave it stock at zero degrees? As always thanks for all your help!
I think initial timing should be around 10 degrees advanced as a starting point. With the engine running, take a look down each carb throat and make sure no fuel is dribbling out of the venturii's. If it is, find out why. I would also use a carb sinc tool to make sure all the throttle plates are even. Once you done that I would start adjusting the idle mixture on each carb. That's for starters.
Just wondering, I've never run a holley 94. Do you run vacuum to them ? Or is it all mechanical ? If so, should it run to all 4 in a multi carb set up?
IIRC out of the box they will have 51 jets. If running non progressive that may be a tad too big. How much vacuum do you have at idle? Would help to know what intake you have and whether you are running progressive or not. If it this one, it is a direct port unit and will not run well as a non progressive.
94’s only have a Venturi vacuum used exclusively for the 49 thru 53 loadamatic distributor. The vacuum ports are normally closed off when using other distributor adaptations. Examples… electronic or GM distributors.
94s do not run well in a multiple carb setup unless they have been modified to do so. Even then they are not really suitable for a SBC, especially if you are running a stock distributor requiring vacuum advance. The cam will have a big effect through the range but especially at idle , as the power valves open when manifold vacuum drops below the number on the power valve. ( inches Hg). The effect of four power valves hanging open will completely overpower any attempts at setting idle mixture using the idle screws. The size of the main jets won't matter at idle, but float level will. Being new from Macs or Speedway does not guarantee anything is correct. In fact IMO if you bought them from Macs or Speedway, you will have problems with them ! I am no longer a Holley dealer , so cannot tell you if it is still the case, but a few years ago Holley was still selling new carbs in this style, probably why Macs ( Ecklers) decided to call them Chandler Grove carbs. Chandler Grove was the designer ( Ford owned the design rights) of these carbs and the manufacturer for 12 months production , after which Ford gave the rights to Holley over a few cents ). They were never meant to be used in a multiple carb situation.
Neither were many , many other carbs but somehow , we hotrodders have used them , in applications they weren't designed for, successfully , for many years .
Some info on the carbs and multiple carb set up https://www.motortrend.com/how-to/0803ct-holley-94-carburetor/
I just went through a second heart break with this manifold. First was with Stromberg 48’s and the second with Rochester 2g. Same problems both times. Great low end with nothing over 3000 or a strong top end that couldn’t pull you away from the curb. This manifold is not a direct into the cylinders like a Manifre. I found no way to have a progressive linkage on either setup.
https://www.jalopyjournal.com/forum/threads/very-basic-multiple-carb-sync-tech.124624/ This should get you started…
That is qualified by my first sentence...I agree, " Modified to do so" , is the hot rodders way. I have successfully modified 94s to work in linear multi carb situations, however in this particular manifold design it is more difficult to make them progressive, or even to stagger jet them. I am sure it can be done but imho the effort would not be worth the final result. I think four new 97s would be a better setup. 94 power valves are pretty much on or off, Strombergs can at least be made ( adjusted) to be somewhat progressive, and there is a variety of associated fuel metering available. The 94s just open or close a fixed delivery channel/ drilling. The only thing you can do is either block off one feed drilling or drill and tap them for jets from a different source ( Mikuni motorcycle jets may work with a lot of effort.) In an inline multi carb situation, I block off one feed with a small lead shot , that can be removed at a later date if necessary.) I have not tried to install jets.
VERY TRUE! Before worrying about jetting, need to install a vacuum gauge and see what kind of vacuum you have; and what the vacuum is doing to the power system. Holley AA-1 (94's) use a vacuum power system. Stromberg EE-1's (97's) use a mechanical power system. hrm2k mentioned the Rochester 2G series, which also has a vacuum power system, but vacuum springs of different values are readily available, plus there are more than a dozen calibrations of the Rochester power valve. NOT saying you cannot make the Holleys work; but for me it would be MUCH more difficult than either the Strombergs or the Rochesters Jon