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Race it, Don't rice it!
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Good to see the paper work. I wonder if there is a way to confirm that engine SN with something on the paper work.
I see the short block specs so I think for now it's reasonable to think the short block is good and so the next step is verifying the heads and age on those.
 

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Discussion Starter · #44 ·
I sent a few pictures of the carb and charcoal cannister, and was hoping for some guidance
on the vacuum hoses as there laid out now.
Basically I'm asking apart from replacing any cracked hoses and caps, is the current vac hose
setup functional. I know it's not the original layout but just want to make nothing major wrong.
I admit I know very little about what vac hoses are needed. Thanks
The 42GM on the block identifies the casting mold used.

Bogie
Cool info, thanks for that
 

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Discussion Starter · #45 ·
I sent a few pictures of the carb and charcoal cannister, and was hoping for some guidance
on the vacuum hoses as there laid out now.
Basically I'm asking apart from replacing any cracked hoses and caps, is the current vac hose
setup functional. I know it's not the original layout but just want to make sure nothing major wrong.
I admit I know very little about what vac hoses are needed. Thanks again
 

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Vacuum lines.
You need a dedicated vacuum hose for your distributor vacuum pot. Plug it into the capped port on the drivers side of carb.
You need a dedicated separate hose for the pcv valve. It plugs into the spot you currently have it on.
the bigger hose beside your fuel inlet is a carb vent line to your charcoal canister. Not needed if you’re not using the canister. If you want to use the canister let us know, we’ll tell you how to hook it up.
the smaller black hose beside the inlet I can’t see where it goes.

here’s an emissions decal for your car. It might be for a Pontiac 301 but your 305 Chevy would be the same.



 

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Discussion Starter · #47 ·
Vacuum lines.
You need a dedicated vacuum hose for your distributor vacuum pot. Plug it into the capped port on the drivers side of carb.
You need a dedicated separate hose for the pcv valve. It plugs into the spot you currently have it on.
the bigger hose beside your fuel inlet is a carb vent line to your charcoal canister. Not needed if you’re not using the canister. If you want to use the canister let us know, we’ll tell you how to hook it up.
the smaller black hose beside the inlet I can’t see where it goes.

here’s an emissions decal for your car. It might be for a Pontiac 301 but your 305 Chevy would be the same.



It looks like the distributor hose is connected to the PCV hose, why did they do that?
Should the unused ports on top of the cannister be capped or it makes no difference?
That smaller hose beside the inlet is a short hose that goes into a port on the carb
at the front lower side of the electric choke. You can see it at the bottom of the choke in the picture.
What is that small hose for? And thank you!
 

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They teed it togethor because they didn’t know any better and it was likely easy to do.
‘If you’re not using the canister just leave as is. Not hurting anything. Don’t take it off and throw it away. They’re hard to find.
I think that small hose is an air supply for venting the electric choke coil. There’s a vacuum port inside the choke that pulls air past the coil to keep it from overheating.

I bought a 80 t/a off the showroom floor in the spring of 1980. Was yellow with the non turbo 301.
what color is yours?
 

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Discussion Starter · #49 ·
They teed it togethor because they didn’t know any better and it was likely easy to do.
‘If you’re not using the canister just leave as is. Not hurting anything. Don’t take it off and throw it away. They’re hard to find.
I think that small hose is an air supply for venting the electric choke coil. There’s a vacuum port inside the choke that pulls air past the coil to keep it from overheating.

I bought a 80 t/a off the showroom floor in the spring of 1980. Was yellow with the non turbo 301.
what color is yours?
Ok, choke vent makes sense. And I did see on a youtube video that the distributor has its own port.
That must have been some feeling driving out the showroom in brand new TA, I bet you still remember it well.
Mine is black with the gold firebird on the hood. Has T-tops too, just like my 1987 Monte Carlo SS had.
Great memories, conceived our first child in that car, when we lived in the States.
 

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Discussion Starter · #50 ·
Seen that emissions label decal, which is very helpful, thanks RWENUTS.
It takes 2 weeks to get parts from the States, so I was going to order these now.
I can't even get the air filters in Ireland. What air filter if not Fram?
Liquid filled fuel pressure guage or air? Is air filled is more accurate?
Holley 803 regulator looks like the best option.
Seen on youtube a guy banging on about the fuel sitting in line getting hot.
Is this a concern, wasn't sure if it applied to what i'm thinking.
Font Gauge Measuring instrument Clock Auto part
 

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You really need to invest in a service manual that covers that year. Whether that is a paper cover Haynes or something similar or hard back Motors Manual or if you can find an original GM service manual. I appreciate doing this from Ireland will be harder than in the States but you will find life with this machine a lot easier with book info in your library.

Since you apparently don’t need to pass emissions a lot of this will just help you clean up and organize the engine room.

The vacuum advance really should come off the carburetor. The Carter which these days is made by Edelbrock the Performer being the equivalent to the Carter AFB while the Thunder is the equivalent to the AVS. The AFB carries the secondary air valve below the secondary venturies and uses a counter weight to determine when and how much they open. While the Thunder has the air valve above the secondary venturies and uses an adjustable spring load to control when they turn on and how much air they will pass. Beyond that they are pretty similar carbs. Edelbrock has made several improvements on the AVS the latest being the AVS-II which acquired annual boosters on the primaries.

On the front both have vacuum ports for the vacuum advance system. In your picture both are capped. Looking from the front of the carb the one on the left that is positioned a bit higher than the one on your right is the timed port. The port on the right that is lower of the two is the manifold source port. Now cam event timing and compression have some to do as to which port will work best for you. This gets to be something you have to tinker with to see which satisfies most requirements.

- Basically a mild OEM type cam with low compression will want full time manifold vacuum. This will idle the best without needing so much curb idle screw. This can, also, hold true of a big cam and low compression.

- High compression regardless of cam can be hard to crank over because the cam needs a lot of base timing to idle well if at all. Here you can mess around with less base easing the cranking load on the starter and use full time vacuum to add advance at idle once the engine fires. Or you can separately switch the ignition from the starter to give it a running start before dumping the ignition on it while using a lot of base advance then use the timed port with a little slower centrifugal and the timed port to put in a little more to the base as the throttle opens.

You have to mess around with this stuff to see what works best with your set up, overall gearing and environmental considerations from cold to hot, dry to humid, flat terrain to mountainous will impact finding settings to where the engine starts easy, idles clean, comes through the carb transition to main metering without hesitation and doesn’t get into detonation anywhere. You just have to play with this stuff to see what the motor likes best.

I have found that the best cleaning for carbs is to purchase a 10 liter, heated, ultrasonic cleaner and here in the US a couple 1 gallon GUNK carb cleaner cans. You’ll find that once clean using a hobby tool like a Dremel with a buffer and some rubbing compound will clean and polish the exterior and it will stay that way for quite a while. Buffing polish compound on the intake will clean and preserve its look as well.

Bogie
 

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Have you even checked fuel pressure?
You might not need a regulator.
Look in the carb while it’s warmed up and idling. If you see any raw fuel then you need to fix that. A simple float level adjustment might fix it.
An alternative to a regulator is a fuel pump rated at 5.5 psi. Edelbrock has one.

You’ll likely shoot me if I told you I sold my 70 chevelle LS6 4 speed to buy the trans am. The trans am was traded off in 82 for a truck.
 

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Discussion Starter · #53 ·
Have you even checked fuel pressure?
You might not need a regulator.
Look in the carb while it’s warmed up and idling. If you see any raw fuel then you need to fix that. A simple float level adjustment might fix it.
An alternative to a regulator is a fuel pump rated at 5.5 psi. Edelbrock has one.

You’ll likely shoot me if I told you I sold my 70 chevelle LS6 4 speed to buy the trans am. The trans am was traded off in 82 for a truck.
You must have really wanted that TA, yellow must have been rockin!
Trading it in for a truck hurts, but i'm sure needs must.
I had to sell my Monte when we moved back to Ireland, cause my Dad was sick.
Really wish I brought it home with me, but the move was complicated enough as it was.

Not checked it yet, dont have a guage, thats why i was going to order one.
I seen a youtube video on that with the carb dripping at idle, so I will check that when
I get the sparkplug replacement for the one I broke.
Sad to say they don't even carry that type of plug. So had to order it in.
You guys don't realise how lucky you are in the States, when I asked them for a regulator,
they hadn't a clue what I was talking about. Told me to order it off at English racing website.
 

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Discussion Starter · #54 ·
You really need to invest in a service manual that covers that year. Whether that is a paper cover Haynes or something similar or hard back Motors Manual or if you can find an original GM service manual. I appreciate doing this from Ireland will be harder than in the States but you will find life with this machine a lot easier with book info in your library.

Since you apparently don’t need to pass emissions a lot of this will just help you clean up and organize the engine room.

The vacuum advance really should come off the carburetor. The Carter which these days is made by Edelbrock the Performer being the equivalent to the Carter AFB while the Thunder is the equivalent to the AVS. The AFB carries the secondary air valve below the secondary venturies and uses a counter weight to determine when and how much they open. While the Thunder has the air valve above the secondary venturies and uses an adjustable spring load to control when they turn on and how much air they will pass. Beyond that they are pretty similar carbs. Edelbrock has made several improvements on the AVS the latest being the AVS-II which acquired annual boosters on the primaries.

On the front both have vacuum ports for the vacuum advance system. In your picture both are capped. Looking from the front of the carb the one on the left that is positioned a bit higher than the one on your right is the timed port. The port on the right that is lower of the two is the manifold source port. Now cam event timing and compression have some to do as to which port will work best for you. This gets to be something you have to tinker with to see which satisfies most requirements.

- Basically a mild OEM type cam with low compression will want full time manifold vacuum. This will idle the best without needing so much curb idle screw. This can, also, hold true of a big cam and low compression.

- High compression regardless of cam can be hard to crank over because the cam needs a lot of base timing to idle well if at all. Here you can mess around with less base easing the cranking load on the starter and use full time vacuum to add advance at idle once the engine fires. Or you can separately switch the ignition from the starter to give it a running start before dumping the ignition on it while using a lot of base advance then use the timed port with a little slower centrifugal and the timed port to put in a little more to the base as the throttle opens.

You have to mess around with this stuff to see what works best with your set up, overall gearing and environmental considerations from cold to hot, dry to humid, flat terrain to mountainous will impact finding settings to where the engine starts easy, idles clean, comes through the carb transition to main metering without hesitation and doesn’t get into detonation anywhere. You just have to play with this stuff to see what the motor likes best.

I have found that the best cleaning for carbs is to purchase a 10 liter, heated, ultrasonic cleaner and here in the US a couple 1 gallon GUNK carb cleaner cans. You’ll find that once clean using a hobby tool like a Dremel with a buffer and some rubbing compound will clean and polish the exterior and it will stay that way for quite a while. Buffing polish compound on the intake will clean and preserve its look as well.

Bogie
Ok that's useful tips, i will switch the distributor vac to carb and see if any difference.
And i fully intend to clean up engine bay, when/if i get it sorted.
The interior needs a few things doing also. Hard to get time with wife and 3 kids.
She's already busting my ass for spending more time on the car than the kids.
Ahh, we'll get there.
I have a Haynes manual, first thing i bought off Rock auto. But it seems very basic.
There is no test, not even a safety. If there was I wouldn't have bought it, as I would be worried it wouldn't pass.
Thanks
 

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Race it, Don't rice it!
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8,412 Posts
Ok that's useful tips, i will switch the distributor vac to carb and see if any difference.
And i fully intend to clean up engine bay, when/if i get it sorted.
The interior needs a few things doing also. Hard to get time with wife and 3 kids.
She's already busting my ass for spending more time on the car than the kids.
Ahh, we'll get there.
I have a Haynes manual, first thing i bought off Rock auto. But it seems very basic.
There is no test, not even a safety. If there was I wouldn't have bought it, as I would be worried it wouldn't pass.
Thanks
take the kids with you and she can’t complain about nothing, or trade her in for another cool car.
 

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Discussion Starter · #58 ·

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Race it, Don't rice it!
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No liquid. It's not needed and add a potential for problems your don't want.
If a liquid shows up cheap, you can pull the rubber plug and drain it.
 
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