[ANDYA]

Any updates? I'm wondering how your car is running with the annular booster carb as I'm thinking of going that route with my engine combo.

[Chris-Austria]

I drove only once and cannot say a lot at the moment since I'm adjusting it now. I got an AFR meter that I will install now and test drive it next time there is no snow.
I'll give you an update!
(the first drive was well, but I think it ran too rich...)

[shaker455]

Originally Posted by Chris-Austria

I got the carb today and checked all jets, bleeds...

The Speed Demon 850cfm annular has the following specs:

High Speed Air Bleed 33
Idle Air Bleed Size 73
Primary Main Jet 76
Primary Power Valve 6.5
Primary Pump Nozzle Size 33
Secondary Main Jet 84
Secondary Pump Nozzle Size 33
Throttle Bore: 1.75"

Now.. do you think this should work for my engine?
I installed it and had to change the float levels (was at 3/4 of the glass) and turn the idle mixture screws about 1 turn in. Runs really smooth now, but I didn't have the chance to drive it yet. Will have to adjust the throttle cable tomorrow.
When adjusting the idle can I plug the vacuum gauge on the front of the carb? I guess I need manifold vacuum, not ported?

Can I use a T and connect power brakes and PCV on the rear port of the carb?

I would keep PB and PCV seperate

[Tom Vaught]

Originally Posted by shaker455

I would keep PB and PCV seperate

Agree, not a good idea to hook them up together and there are specific places on stock and aftermarket manifolds for each connection.
Race manifolds and pure race carbs being the exception. Even then the back wall of the plenum could be drilled to add a separate port for one of the two devices.

Tom V.

[Chris-Austria]

I changed the configuration and now use the port on the back of the RPM manifold for the power brakes and connected PCV on the back of the carb.

Drove the GTO today with my AFR meter. Idle now is very good, at about 13.5 to 14:1 and 800rpm.

Cruising with low rpm's create about 13.5:1 but higher rpm's will make it run a little too rich.. up to about 12.5:1.
At the moment when I suddenly increase rpm's it will get lean for a moment (up to 15:1) no matter if it's at low rpm or higher rpm's to WOT. WOT will show 12:1 after the short lean condition.

I need to do some adjustment but it ran pretty nice even with this AFR and the short lean conditions.
I'll change the power valve from 6.5 to 7.5 or 8.5 and maybe use smaller jets. If the power valve won't solve the lean condition I may change the pump nozzles to a bigger size.

[shaker455]

12.5 is ideal WOT.
You might need some more pump shot with your cubes
I would leave the PV and do not drop jet size, that will make the spike worse.
If anything go up on primary jet size as the spike will reduce.

[Tom Vaught]

Pump Shot, as was mentioned first, then larger squirters, then 50cc pump on the front of the carb, (swap front and rear bowl parts, pumps, and related hardware), do not mess with the power valve or the jetting except to go upward in size.

Tom V.

[shaker455]

the Demon have 30cc pumps front & rear .

[Chris-Austria]

Today I checked the jets and power valve. There was a 4.5 power valve.. I replaced it with a 7.5.. at idle I have 15" hg so I guess it should be fine now.
Couldn't drive the car since there is snow, will have to test what happend later.
Until then I will try to get the cold idle better.. it runs too lean when cold, I will increase the cold idle speed and try keeping the choke open a little later.
Hot idle is now 14:1 and 15"hg (highest reading I could get).