what should I do with this intake?

So, last night I tried to rebush my rochester 2GC. I have 4, they are all different from each other in one way or another. Well i ruined the one that came on the buick skylark engine thats in my jeep. It was close before i wrecked it. I put the throttle base from the Dauntless on the skylark carb body because the dauntless one had a wrecked power valve. Runs like sheet. off idle stumble. bottom vacuum is always vacuum, where it was not before. I replaced the accelerator pump that was missing the bottom spring and was in its bore somewhat sideways. Cant get the idle timing down below 25* or so with vacuum advance plugged into distributor. total poo. This is the result.

so, really the result is that I destroyed my carbs to make sure I could put in this intake and a holley 4 barrel. Im going to buy it tonight i think. Got a little nervous when The intake wouldn't fit, duh.. the HEI distributor was in the way. Pulled it and it fits as good as the old intake. I will actually machine the intake to fit around the distributor.

 

I've had nothing but troubles with my holly 390 on my v6 for years. It has always had a stumble when I get on it where as the 2G on the stock v6 runs excellent.

 

What intake manifold are you running?

 

Often, a larger power valve will cure this.
Less often, changes to accelerator pump squirter size or pump cam are needed.

 

Regardless, the carbs i have are wore out junk and i really need to start narrowing down problems and get some reliability into the engine. The holley has many available parts, tech services, electric choke and a warranty. Its also NEW. Since I now have a running vehicle that is registered licensed and insured i have entered the new phase where its not just yard art. Buying new parts instead of fixing or rebuilding junk I find alongside the road for free to create reliability is my goal.

funny how fast it goes from "whatever you can get to work together" to "make it reliable and safe" happens.

 

The Holley is new, but don't plan on it being a bolt on and go installation.
They are a universal carb, meaning you'll probably have to make changes to the carb to get it running properly.

 

Please share the machining mod to keep the GM HEI distributor. It's the one thing i disliked about this intake. I hate points...... I have thought about cutting and lengthening the dist to gain clearance, never occured to me there might be enough material to machine the intake.

 

you can just grind down the holt hole a bit. Its a real common thing to do. I think I might grind it off at an angle like all the steel intakes with HEI and counterbore it to accept a socket head bolt. I'll take a pic when I'm done. Im sure it will not be anything anyone hasn't seen or done before. I am concerned about the thinner material being aluminum rather than steel.

 

goes on tomorrow

When you grind the intake, do you grind the intake on the face of the hole or just an angle to get the distributor housing to clear? I can machine that part flat and use a button head. will it clear and still give me the strength so that it does not crack? I ground an angle on the steel intake, but it still did not allow clearance for a button head. I was thinking maybe a taper head, or should I just machine it to 3/16 parallel to the intake sealing surface?

Thanks

 

Thats how i ground my cast intake. still couldn't get a button head to clear. I will make it happen tomorrow though. Thanks.

 

47, can you please take a couple pics that show us just how much and where you ground?

 

i wil take pics of my old intake and the new tomorrow.

 

I was going to try and get fancy and mill off material and all that.. it just wasn't going to work better for all the effort it would take. This is the problem.

This is the solution


this is how it works with a button head. You install the intake without this last fastener, install the distributor, then the button head fastener, then the cap.

I did grind the button head on the side facing the cap when tight to allow extra advance if needed but the cap plug post still does not clear the button head entirely. I hope i don't need that much advance.

 

Thank you! Looks like an easy project, my future plans are now hei and Howell FI.

 

HA HA. got it together and started it up. Cant drive it yet because I need to fabricate an accelerator linkage. Need to adjust high idle, too many RPM. After it warmed up to operating temp, had to adjust the idle mix screws in to turn down idle. I need to buy a vacuum gauge. Set timing to 8* advance with vacuum plugged. Great thing about this carb is that the vacuum port for timing advance is really for just that. Zero vacuum at idle, like it is supposed to be. Timing advances like it is supposed to when you give it throttle, falls back immediately off throttle.

out of the box it runs better than any of my wore out 2 gc's did. I am so far truly impressed. Its frigging killer!