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bitsilly
28-03-08, 03:20 PM
OK, no p*ss taking but I have fitted a servo for the clutch, and one for the brakes, I also have a PCV valve , and a Mallory HEI distributor with a vac advance.
So is there a best method for connecting their vac service?
My demon carb has a port specially for the PCV, so I used it for that.
Then it also has two other ports, one is intended for the dizzy vac advance (and the vacuum there is ported or timed) so I think that is the best one for the HEI Mallory???
The other port on the carb I would like to keep accessable for diagnostics as there is very little room for the servo pipe but I,m flexible!

What I'm getting at is; is it better to connect the servos to the manifold or carb vacuum, that said, can anyone tell me which holes to use for vacuum on an edelbrock airgap chevy 350 manifold? Or should I be tapping into the air filter for anything?

PS I have tried searching for this first honest!

Many Thanks

craggle
28-03-08, 03:26 PM
PCV can go into the port on the carb

Use the timed port for the distributor vacuum.

My vacuum brakes go into the manifold. Behind the carb is a port tapped in the top of the manifold. I have a 90 degree fitting screwed into this and a pipe connected to the servo. In the pipe is a non return valve to stop petrol vapor going down the pipe and it prevents the servo being damaged if the engine backfires.
Maybe you could tee the vacuum clutch of the vacuum brake pipe.

Craig.

bitsilly
28-03-08, 03:46 PM
That figures, so I will use the carb connections as recommended, blank off the one for diagnostics and the servos get attached to the manifold.

The take off behind the carb in the top is really tight with the demon card on it, I would need to get something made up unless it's a common problem, the clearence is approx 12mm.

However, on either side of the dizzy there are two blanked off holes which are accessible, but for the life of me I can't remember what is below them!

Is it OK to run two servo's together with a t-piece to one port then?

If the two either side of the dizzy are out I guess I'll have to run both servos to the spare carb port??

Cheers
Ed

craggle
28-03-08, 04:14 PM
I have the performer RPM intake and it has only one port behind the carb. The ones at the front are for the heater pipes and temperature senders. I think the airgap manifold is the same layout.

The 90 degree fitting on my manifold is very low. I will measure it tonight and post a picture if required.

Craig.

bitsilly
28-03-08, 04:32 PM
Craig, if you could just check the height of the fittment that would be great.

The ports in question are at the back, at the corners of the manifold one one either side of the dizzy, I don't think they are an option but would feel better if someone who knows could say what they are.

Thanks for your help

craggle
28-03-08, 04:59 PM
They are not for vacuum. I imagine they go into the water channels at the back of the heads. Not sure what use they are but they are definitely not vacuum ports.

I will measure the height of the fitting in a while.

Craig.

craggle
28-03-08, 10:01 PM
Right

Measured my little cast steel 90 degree thing and it sits about 3/4" above the surface of the manifold.

The engine was supplied by Re-Power (Roadcraft Repower) (http://www.roadcraftuk.co.uk/)

I can't see them on the web page but he must sell them. May be worth a chat with him to see if he can suggest a lower alternative.
How much space have you got between the air cleaner and the bonnet? Maybe you could fit a 1/2" heat spacer under the carb to give a bit more clearance.

Craig.

Purple AK
28-03-08, 10:05 PM
A Banjo Fitting might give a little more room

bitsilly
28-03-08, 10:42 PM
Cheers gents, I have 12mm so a bit too tight.
Craig, is there any thread showing as part of that height?
And does anyone know a suitable banjo fitting or where I could ask for one?
Has anyone just drilled into the bloody manifold and tapped a thread?
Does anyone want to swop a part complete Ram for an MX5?
Need medication.

Purple AK
28-03-08, 11:05 PM
Cheers gents, I have 12mm so a bit too tight.
Craig, is there any thread showing as part of that height?
And does anyone know a suitable banjo fitting or where I could ask for one?
Has anyone just drilled into the bloody manifold and tapped a thread?
Does anyone want to swop a part complete Ram for an MX5?
Need medication.
Seems to be the easier option ;) Medication supplied :D

Miket
28-03-08, 11:08 PM
Seems to be the easier option ;) Medication supplied :D

Nice bit of pussy on your desk. ;) :D :D

Purple AK
28-03-08, 11:16 PM
Nice bit of pussy on your desk. ;) :D :D
Your eyes belie your age Mate ;)

Miket
28-03-08, 11:23 PM
Your eyes belie your age Mate ;)

I might be getting on a bit, but I can still spot a nice pussy. ;) ;)

Purple AK
28-03-08, 11:31 PM
I might be getting on a bit, but I can still spot a nice pussy. ;) ;)
There you go! A Full Frontal Shot. And a Posed Shot ;)

runt
29-03-08, 03:56 PM
He's gorgeous Chris, my wife wants to know his name!

Paul.:)