Final details - need help
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
Final details - need help
I am making slow but constant progress on my numbers matching 68 350/350 but is now internally a 383. Hopefully getting this thing started before October. I have a couple questions related to holes that need to be filled, plugged, etc. Yes, Yes, I know the wire looms are not done yet. And yes the carb looks bad but it was done by Lars and I am not touching it! Yes I know I gave up 75 to 100 hp by keeping the numbers matching heads.
I appreciated any info provided.
But first here is how things look so far.
This vacuum line, what is it for? Can I just plug it during break in?
This vacuum line under the fuel inlet, what is it for? Can I plug it during break in?
This vacuum fitting. Which direction should it point. What is it for? Can I plug it during break in?
How about this tapped manifold hole. On the other side goes the heater hose return fitting. So what is this one for?
I appreciated any info provided.
But first here is how things look so far.
This vacuum line, what is it for? Can I just plug it during break in?
This vacuum line under the fuel inlet, what is it for? Can I plug it during break in?
This vacuum fitting. Which direction should it point. What is it for? Can I plug it during break in?
How about this tapped manifold hole. On the other side goes the heater hose return fitting. So what is this one for?
Last edited by AWilson; Aug 4, 2009 at 10:28 PM.
Drifting
Joined: Jul 2002
Posts: 1,697
Likes: 3
From: Woodinville WA
It looks like you have vacuum advance connected. The line on the manifold in the last picture is for the main vacuum that operates your headlights and wiper door. It doesn't matter much the way it points. Mine points forward.
There should be one at the base of the carb in back for power brakes if you have them. One of the two in front can probably be connected to your PCV if you are running one. If you have some you don't need, just plug them.
Engine looks good, keep the pictures coming.
There should be one at the base of the carb in back for power brakes if you have them. One of the two in front can probably be connected to your PCV if you are running one. If you have some you don't need, just plug them.
Engine looks good, keep the pictures coming.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Looks great! 
Fitting in the 2nd picture is for the valve in the stock air cleaner, I believe. If you're using an aftermarket cleaner, you can plug it.
No help on the 3rd one
The manifold fitting is for the vacuum modulator, or if on a manual car this may be where the engine vacuum for the headlights and such are. I no longer have my factory assembly manuals for the C3, but that would be the place to start
Fitting in the 2nd picture is for the valve in the stock air cleaner, I believe. If you're using an aftermarket cleaner, you can plug it.
No help on the 3rd one
The manifold fitting is for the vacuum modulator, or if on a manual car this may be where the engine vacuum for the headlights and such are. I no longer have my factory assembly manuals for the C3, but that would be the place to start
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Pix #2 - that's ported vac. Use a can of WD40 to see where it comes out inside the throat. Sometimes even a small dia wire will slide through so you can see it. Should be above the throttle plates for ported vac. Below throttle plates for manifold vac. Now some ports vent from the fuel bowls and maybe the vac brake canister on carb.
BTW is that the original carb?
Pix #3 - same answer as for Pix #2.
Pix #4 - just another manifold source but for smaller devices as the pwr brake booster attaches to that big plug on the back of the carb next to your manifold fitt'n. Could be for headlight relays.
Pix #5 - would be for a temp sensor. Is that the numbers correct manifold for your '68?
Now my question. When would you like to help my current roller cam sb engine project and contribute your old 327" shaft to a worthy cause?
If you don't want it I'll take it.
Good luck and hope this helps,
cardo0
Last edited by cardo0; Aug 6, 2009 at 08:11 PM. Reason: more info
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
Pix #1 - its looking good.
Pix #2 - that's ported vac. Use a can of WD40 to see where it comes out inside the throat. Sometimes even a small dia wire will slide through so you can see it. Should be above the throttle plates for ported vac. Below throttle plates for manifold vac. Now some ports vent from the fuel bowls and maybe the vac brake canister on carb.
BTW is that the original carb?
Pix #3 - same answer as for Pix #2.
Pix #4 - just another manifold source but for smaller devices as the pwr brake booster attaches to that big plug on the back of the carb next to your manifold fitt'n. Could be for headlight relays.
Pix #5 - would be for a temp sensor. Is that the numbers correct manifold for your '68?
Now my question. When would you like to help my current roller cam sb engine project and contribute your old 327" shaft to a worthy cause? If you don't want it I'll take it.
Good luck and hope this helps,
cardo0
Pix #2 - that's ported vac. Use a can of WD40 to see where it comes out inside the throat. Sometimes even a small dia wire will slide through so you can see it. Should be above the throttle plates for ported vac. Below throttle plates for manifold vac. Now some ports vent from the fuel bowls and maybe the vac brake canister on carb.
BTW is that the original carb?
Pix #3 - same answer as for Pix #2.
Pix #4 - just another manifold source but for smaller devices as the pwr brake booster attaches to that big plug on the back of the carb next to your manifold fitt'n. Could be for headlight relays.
Pix #5 - would be for a temp sensor. Is that the numbers correct manifold for your '68?
Now my question. When would you like to help my current roller cam sb engine project and contribute your old 327" shaft to a worthy cause?
If you don't want it I'll take it.Good luck and hope this helps,
cardo0
Thanks for the info. carb is not original for a 68, it is a 69.
The manifold is original to the car. I believe the hole should just be plugged. The Temperature sensor is on the driver side next under the exhaust manifold.
I'll keep the crank for now. I have another 350 engine sitting on the garage floor that might like it some day.
Thanks again.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
I think i remember the port in Pix #2 (on the P-side of carb) was a manifold vac port. And if true could be used for your dist vac can - but verify this as i described before.
And the vac port under the fuel inlet in Pix #3 was for the choke pull-off canister right next to it. It should be a ported vac if you can check it.
Manifold hole in the water passage still a mystery. What else uses hot water behind the T-stat?
BTW where did you get your head work done? Performance out of Phenoix? Do they still pocket port for only $100?
cardo0
And the vac port under the fuel inlet in Pix #3 was for the choke pull-off canister right next to it. It should be a ported vac if you can check it.
Manifold hole in the water passage still a mystery. What else uses hot water behind the T-stat?
BTW where did you get your head work done? Performance out of Phenoix? Do they still pocket port for only $100?
cardo0
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
I think i remember the port in Pix #2 (on the P-side of carb) was a manifold vac port. And if true could be used for your dist vac can - but verify this as i described before.
And the vac port under the fuel inlet in Pix #3 was for the choke pull-off canister right next to it. It should be a ported vac if you can check it.
Manifold hole in the water passage still a mystery. What else uses hot water behind the T-stat?
BTW where did you get your head work done? Performance out of Phenoix? Do they still pocket port for only $100?
cardo0
And the vac port under the fuel inlet in Pix #3 was for the choke pull-off canister right next to it. It should be a ported vac if you can check it.
Manifold hole in the water passage still a mystery. What else uses hot water behind the T-stat?
BTW where did you get your head work done? Performance out of Phenoix? Do they still pocket port for only $100?
cardo0
I used a local recommended shop that I think did a great job. Lets just say though that I could have bought heads for what it cost. But I wanted to keep things original.
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Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
I know you must have just mistyped when you typed "numbers matching 68 350/350" 
Here is a picture of my 68 intake and it looks like someone has drilled and tapped an extra hole in yours, possibly to relocate the temp sensor?
I can't help you with the rest, mine had a Holley on it when I got it.
Here is a picture of my 68 intake and it looks like someone has drilled and tapped an extra hole in yours, possibly to relocate the temp sensor?
I can't help you with the rest, mine had a Holley on it when I got it.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
I know you must have just mistyped when you typed "numbers matching 68 350/350"
Here is a picture of my 68 intake and it looks like someone has drilled and tapped an extra hole in yours, possibly to relocate the temp sensor?
I can't help you with the rest, mine had a Holley on it when I got it.
Here is a picture of my 68 intake and it looks like someone has drilled and tapped an extra hole in yours, possibly to relocate the temp sensor?
I can't help you with the rest, mine had a Holley on it when I got it.
Last edited by AWilson; Aug 11, 2009 at 06:50 AM.
Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY