I have to admit I'm a Holley man. I'm running a 750 HP carb right now.
Nice lookin motor. How bout a zoomed out shot?
I have to admit I'm a Holley man. I'm running a 750 HP carb right now.
My 340 is 30 over with a nice cam,not too radical.I have a RPM intake,4 speed with 3:91 posi,stock exhaust mani's with 2 1/2" stainless exhaust.Craig, you'll get a better answer if you can include some of what your engine and trans combo is. The 3310 is a GREAT carburetor to slap on and go and be very easy to tune to a variety of engines. As a general rule of thumb, the vacuum secondary carbs are for automatics and the double pumpers are for manuals. Also, it's not a good comparison for you to compare your carburetor to an HP model as far as the vacuum for the distrubutor goes. Most of the HP models have no timed spark vacuum port for the distributor because they are meant for radical engines with a low vacuum signal. If your combo is mild to moderate and driven on the street at all, I highly recommend running the vacuum advance. You'll pick a little part throttle acceleration and the mileage will pick up pretty good from the part throttle timing advance. Just my two cents.
Holley. Course my first choice is Thermoquad.
My 340 is 30 over with a nice cam,not too radical.I have a RPM intake,4 speed with 3:91 posi,stock exhaust mani's with 2 1/2" stainless exhaust.
I have tried it and it surges bad! that's why I removed it.I'm hoping to get better response and mid to top end improvement.I would surely run a vacuum advance if I were you. It won't hurt to try it both ways, but I believe you'll find better mileage and response using it.
I have a brand new Edelbrock 750 on my freshly rebuilt 340. It is a bugger to get started after sitting overnight, and has been fouling both the sparkplugs and the oil since it was installed around 400 miles ago. It also goes through a ton of gas, even when I try to keep my foot out of it.
My shop played with it a bit, and I've seen zero improvement and it's possibly even worse than before. Not becoming a fan of Eddy any time soon at this rate.
The 340 is also 30 over, semi-radical cam, new aluminum Eddy heads and air gap intake, with TTI headers and 2 & 1/2 inch exhaust.
I have tried it and it surges bad! that's why I removed it.I'm hoping to get better response and mid to top end improvement.
I'm betting you hooked it up to a straight vacuum port, instead of the ported vacuum port.
Nice lookin motor. How bout a zoomed out shot?
I have to admit I'm a Holley man. I'm running a 750 HP carb right now.
X2 with the Eddie carb.The Holley I bought is still in the box! My Duster sleeps for the winter.It's in my small heated shop.Large enough to play!Thats what mine did.
I don't know about CRAIG but I hooked mine to the appropriate vacuum port and it ran awful.
Oh I like that Marland, is that one of the newer Holleys that has the sight glass on the side of the bowls?
Thanks for being helpfull.Maybe I'll try another distributor! I'll keep my eyes peeled for a new one!Craig the 3310 is a great carb. I've owned a few over the yrs. Most of the time you can just slap them on and go. As for it surging when the vacuum advance on the dizzy is hooked up, that could be due to 2 things.
1. The vacuum advance canister on the dist. may be bad so when you hook the line up it creates a vacuum leak.
2. The vacuum advance canister has too much advance. The best way to limit it is replace the canister with one that has less advance. If it's a Mopar dist. I have a list of what vacuum advance canisters have what for advance.
When working right a mild to moderately built engine will benefit from vacuum advance. Helps keep the plugs cleaner, helps fuel mileage when cruising, and generally helps cold idle warmup. I almost always run vacuum advance distributors.
It could just be too lean, try smaller rods on the big end, if its .070, try a .064
The air gap isn't no help either on the fouling plugs, a heated intake would work much better right now in the cool fall temps. The plugs get fouled out after so long, if the intake exhaust heat is open the motor warms up in a few mins--least the intake does and helps keep the plugs clean. If you must run the air gap in cool temps then you need a powerful MSD system--like a race car has. The plug wires, cap all has to be top notch--just a MSD 8 box won't do it, the plug wires or cap will missfire/crossfire cause the spark energy is so strong it find any weak spots.
There could be other things, like a leaky intake gasket compounding the other problems.
Thats what mine did.
I don't know about CRAIG but I hooked mine to the appropriate vacuum port and it ran awful.
Thanks for being helpfull.Maybe I'll try another distributor! I'll keep my eyes peeled for a new one!
If you're talkin about the Holley HP you posted a pic of, I didn't even SEE a timed spark vacuum port on it. Most don't have one. They are always on the primary metering block just above the idle air screw on the passenger's side and I saw no vacuum port there in your pic. If you hooked it anywhere else, it was probably on manifold vacuum.
Rob I don't know much about the HP series Holley's but a few days ago I read that they do have a timed port and it's located on the base. There are 2 ports right next to one another. One is full time vacuum and the other is timed. I guess they must have the timed port drilled at an angle to go above the throttle blades.