GTR1999

Finishing up installing new 750 speed Demon,I have to make up a 90* 3/8 line to the carb.
Question is where are you running vac for PB & PCV? Tapping the 3/8" pipe out of the back of the carb and teeing into it?Any problem with the brakes? Same for the 1/4" pipe on the right side- teeing for the lights and Dist vac advance?
Thanks,
Gary

killervette666

i dont run PVC but for my power brakes i do use the hole in the back, you can always T it without any problems (i think), as for all the other vacuum lines i used a few Ts to make it all work, seems to be working so far for me.

1979toy

I would run the power brakes off of a dedicated connection that is not shared.
I run my light vacuum off of the back of the carb. and the transmission vacuum from a tap in the intake manifold.

JoeRags

I too run the brakes off a dedicated line tapped in the intake manifold

GTR1999

Well the paperwork I have lists both ways for setup- teeing off the back for the PB & PCV and then not to? The plug in the intake is right under the fuel bowl so there is no room to run a line there.

Older Than Dirt

gtr1999, I suspect the heat shield is blocking the hole in the manifold where a vacuum fitting could be installed. You could always try the large port with a tee and see how it works. If you are using the timed port for vacuum advance that would leave you with the small direct manifold vacuum port to use also. It also appears that the heat shield is flat (not bent) to clear the accelerator pump arms. The arms will bottom out against the heat shield?

GTR1999

The bowl is over the hole for sure,I could always mill a hole in the plate but there's not room under the bowl where a fitting would make it. The plate is flat, I was going to offset bend it but decided to slot the area under the arms so this keeps the shield a little higher.

GTR1999

The bowl is over the hole for sure,I could always mill a hole in the plate but there's not room nder there. The plate is flat I was going to offset bend it but decided to slot the area under the arms so this keeps the shield a little higher.

Older Than Dirt

Ok, I can see better now. I suspected you were aware of that, it just didn't occur to me you had slotted the shield. BTW, it looks good, good job!

GTR1999

OTD-Thanks, now you can see why I can't get a fitting in the intake. I'll just have to get a better look at it tonight.
Gary

Older Than Dirt

Gary, CC shows a part #303319 intake fitting that looks to be a elbow type low profile one port fitting. I don't know if it will work in your case but you might want to look at it.

ferndog4

I have the same Holley heat shield but it appears we have two different types of installation directions. My speed shop installed it the other way round. They installed in the order of manifold base to Carb: basic carb gasket, the Alumin. heat sheild, and then the thicker gasket. No need to cut anything this way. My vacume lines run fine from each of the ports. I am puzzled?

mani. base->carb gasket->Alum. heatshield->thick black gasket->carb

GTR1999

OTD, thanks I emailed Barry Grant and they said to either Tee it or to get the low profile 90* el that Edelbrock sells. I didn't get back to work on it yet.

Fern- It was my assumetion that the thicker gasket went on the intake under the shield to raise it away from the heat? I looked at some other Demon/Holley setups and they were the same.

Gary