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The previous owner of my '63 C20 had installed a 305 and TH350 from a '78 Camaro. The motor and trans had been rebuilt. It runs well, but there are a few quirks. My brother-in-law is a mechanic and a drag racer and had some suggestions. He also, however, is wealthy and for him cost is no object.

Being this isn't my reality, I hoped I could get a 2nd (or 3rd, 4th, 5th... ) opinion on his recommendations.

Here are the problems/specifics.

1) The choke is disconnected so the truck runs rough until it warms up a bit.
2) The carb is a Carter 2BBL and the engine has its stock HEI distributor.
3) There is a fairly significant oil leak at the intake manifold. I believe it's just the gasket, but because the manifold, distributor, etc., he said it's upgrade time.
4) The vacuum advance on the distributor is disconnected.

Here's what he suggests:

1) Holley 4BBL 600CFM carb with vacuum advance and electric choke
2) MSD HEI distributor and coil with a MSD 6A "box"


I haven't priced everything yet, but this is shaping up to be ~$1000 worth of upgrades. My goal is decent power with decent fuel economy. I don't want a racecar, just to have the power available for hauling, etc. I was also hoping to spend about half ($500).

Specifically:

1) What kind of real-world performance could I expect with the dist/coil/box upgrade? Do I need the box or will just the distributor make a difference?
2) The 4BBL seems like a good upgrade. Any thoughts?


Thanks in advance for any suggestions.



John

You didn't mention any obvious ignition problems, so I'll assume there aren't any present. The factory HEI has plenty of jolt, and I wouldn't replace it just yet. The MSD units are great, and I've used them in turbo applications where the cylinder pressures call for more voltage at the plug. If you insist on an ignition upgrade and your current distributor is in decent shape, you can buy the 6A box for it. I believe MSD still makes a plug-in harness to connect it to the external coil HEI too. I'm digressing. Leave your HEI alone right now if it is in good shape. The carb & manifold will give you a noticable performance gain, IMO, but don't go larger than the 600cfm carb for an otherwise stock 305.
Chhers, MIke V

Woops, you have a V*, and most likely the in-cap HEI coil, so you would not require the external coil kit. "more coffee please".

Mike's right, the HEI is all the distributor you need for the street. The caveat to that is HEIs were installed and setup for SMOG, and recurving might help it's performance.

If it was me I'd sort out what's there now. The disconnected vac adv is definitely not helping performance any. Assuming you still have manual choke cable you might be able to hook that back up. Intake manifold oil leaks are common. It's a little tricky setting the intake manifold down without moving front or rear gasket, unless you do it often.

Forget the Holley, it's a nice carb for racing, but a maintance hog other wise. A good Quadrajet would do as well for the street.

How far north are you? I'm in central CA by Stockton.

Larry

I would rebuild the HEI & modify the advance mechanisms. I would get an aluminum intake Edelbrock performer or Weiand. Get a Q-jet & rebuild it or an edelbrock performer with electric choke. If you want to stick with a low budget an aluminum intake off a mid 80,s 305 works real good & are cheap from salvage yards or swap meets.

Thanks for the replies everyone!

I wrote the thread early this AM, and I don't know why I put coil down...my bad on that.

I also forgot to mention that it has a Edelbrock intake manifold. There's a plate that allows for the 2BBL to bolt on, so adding a 4BBL should be easy. I love the idea of a Quadrajet or Performer with electric choke.

My nephew and I also had a thought today. Sorry for the rookie question, but here goes:

The PCV valve on the truck was sitting loose in the 1 1/4" valve cover hole. We installed a tighter-fitting grommet and the truck ran much better. I assumed it was because of eliminating the vacuum leak. The PCV valve does connect to the carb, but is there a chance that the new grommet also increased pressure in the valve covers? There's no breather on either valve cover; the oil fill cap fits snugly. Would pressue cause the oil leak?

Thanks again.

LGriffin: I'm near Santa Rosa, about 1 hour north of San Francisco. We're about 150 miles apart. Glad to see someone nearby!

Intake manifold advice for a 100% no leaker. Do away with the front and rear gasket on the intake manifold. When you reset the intake manifold, use the intake to head gasket. For the front and rear, use a 3/8" bead of silicone sealer. Then set the intake into place. After the silicone has set, you can cut it smooth with a razor blade for a neat look, or leave as is.


I just did an intake on my buddy's 1971 Jimmy. My procedure was to Gasgacinch the head and the intake gasket. Then I put a small wipe of silicone around the water port. Before setting the gasket in place, I put a small dab of silicone at the corner where the head meets the block. I then set the gasket on the head, after the Gasgacinch becomes tacky. Then I set a thin wipe of silicone, again, around the water ports, on the gasket itself. A 3/8" bead of silicone front and rear mating surface, then set the manifold onto the valley. Follow the torque sequence first snugging the bolts by hand. Ultimately the torque is 25 ft. lbs. So I take then to ten, then twenty, then twenty five. Then go over them again. Of the dozen or so intakes I have done, nary a leaker in the bunch. And some of those were fleet vehicles that got a lot of mileage and abuse!

You need another vent besides the pcv valve. Either a tube going to the air filter or a vent type oil cap.

I'll fix that then. Thanks for the help everyone!

If there's a hole in each cover,you can run a PCV in each cover and T the hoses together before they go into the carb. I did that on my 355 and it works fine-runs great,doesn't leak,doesn't burn oil,and looks cool,too.
Some aftermarket intakes are set up for the filler tube;if you only have one place for a vent you might think of drilling out the hole and putting a vent/filler tube in-they're high enough they often can vent without throwing oil over the top of the engine like the vented valve cover cap is prone to do.
Speed