Hi guys Im currently trying to figure out a slight problem I have with my 94 setup, I have a vintage speed 3x2 intake/adaptor to 4 barrel bolt pattern on my Buick 350 V8 with the 3 94s running non progressive but I have the very front carb blocked off as I had a separate issue with it as well the motor was just drinking way to much fuel and running way too rich even at idle, though blocking up the carb helped fix the first issue. I have a Holley low pressure regulator set to just under 3lbs, occasionally this pressure on the gauge changes for no apparent reason, which might be part of my issue, though its not seemed to change recently , Generally driving it and cruising aroung under 60MPH Its fine delivering plenty of power and revs up great through out the rev range, but, around 60MPH, sometimes just over and some times just under 60mph the problem I have is the revs drop for a second then pickup then drop then pickup, almost like a faster stall convertor kind of sound it will keep doing it untill you try and accelerate past 60 which usually im not able too or back off and then just keep to around 55MPH and again its fine, im starting to think it could be something to do with the power valves, Iv heard of lots of issues with these like the gaskets leaking, disolving or being the wrong ones completely and havnt yet been able to check into this (had too much fun driving it lol) plus iv only just started taking it out on the Highway recently which was when I first noticed this problem as before iv always been taking the back roads while working all the bugs out of this newish build, Im pretty certain in saying this is a fueling problem but its just trying to narrow it down a bit more what it could be and Im hoping maybe some of you guys might have some advice or had this happen to you in the past? Im also wondering if there is a different power valve I should put in the 2x2 set up ? ps the photo is of my carbs before I fitted the linkage lol. many thanks in advance Charlie
For anyone that cares this problem ended up being a float not being adjusted properly (too low) and so it had fuel and when trying to accelerate over 60mph it would empty the carb bowl as the fuel wasn't being aloud to fill up the bowl enough to keep up with the consumption of the engine Charlie
I have 94s as well and from what I've read in numerous threads and what my regulator is set to is around 1.5lbs so perhaps your pressure is to high. I have dropped mine a notch lower and things start to run less than favorable. I am also having issues with wetness and raw fuel smell but the pressure definitely affects things.
Running 94's in a multiple carburetion setup requires different power valves than stock. If your carburetors were properly setup as a 3x2 and you changed it to a 2x2 you need to change the power valves in order to reflect the change in manifold pressure the carburetors are operating under.
I have a 6-2 set up (94's) on my 54 Buick 322 engine (avatar), I'm running 4 carbs, the centers are blocked off, I do this with no regulator and have 4.5 - 5lbs of fuel pressure and I've changed the power valves, I run a little rich at idle, not too bad and runs well at highway speeds. During the winter I pull the intake manifolds/carbs and go through them, check the float levels, clean'em up and replace all the gaskets (I use the thick ones). Oh, by the way, last year I checked mileage and got 18.4 miles per gallon with a 3.08 rear end!
Thank guys I rebuilt my carbs just before originally posting this, as a 2x2 set up my reason for this original post was that the car was bucking if you will rev up then almost die the pick up and then die down as said that was because of the incorrectly adjust float level but admittedly checking and going through the power valves is definitely something I need to definitely do and is on the to do list in the very near future also something I want to check is the jet sizes and adjust accordingly, and I have a suspicion my power valves might be the ones that don't seat properly, they were from the Holley 94 rebuild kits in a white box I bought from the old car centre in Langley So might need to talk to Charlie price about better ones or has anyone else got some good contacts to get the correct power valves from? Thanks Charlie
Also with fuel pressure for 94s the rule of thumb I always thought I knew for them was between 1.5-3lbs but no more, mine seem fairly happy around there I could turn it down a touch but they don't leak through the shafts which seems rare for these carbs Charlie
What's the best way to determine what jet sizes one would need? same with power valves? as every motor/carb combo are different what is there out there to work with to help figure it out? Is there a table somewhere? My motor is a stock Buick 350 V8 running 2x2 Holley 94's Thanks Charlie