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RE_Farmer · 05-11-2020, 10:06 AM

Others have addressed the vacuum line issue quite well. Upon further reflection, I mis-stated dates for installation of A.I.R. systems. So, I'm revising my earlier comments for completeness here since I can't edit my previous post.

Quote:

Originally Posted by RE_Farmer

you might look for pre-1976 454cid vacuum layout diagrams.

Edit to (my) post #5

Make that pre-1970 not 1976

IIRC, ~1970 is when they started installing A.I.R. systems. My '72 cars had it. Trucks may not have gotten that treatment until later. 1976 is when cars (trucks again were later, but I don't know how much) started having catalytic converters and went to unleaded gas.

EyezOpen · 05-11-2020, 03:00 PM

Quote:

Originally Posted by Brob

No, I did a good bit of research at the time and what I deduced was that in the earlier days of pollution control, there was a lot of fuel being used for cylinder cooling. Basically the AIR pump was dumping air into the exhaust stream to dilute the mixture. Once all that is out of the equation, the engine can run much leaner. The lighter springs in the distributor affords more advance earlier in the rpm range as well.
I believe the combination of EGR delete, AIR pump delete, and the distributor recurve puts the engine in a sweet spot of pre-emissions tuning. Though we don't have testing here in the state anymore, I have a friend who owns a shop with emissions equipment. We put the sensors in the exhaust stream to see how the mixture looked. He said that my rig would pass testing in every state based on emissions alone. That being said, it would likely not pass a visual as I physically eliminated the pump and all its acoutrements.

Yes, there is quite a benefit to recurving the dizzy..question here did you limit the vacuum advance to 10 inches on the vacuum advance can? If you set the initial at 12 and then advance 22 degrees mechanically then one should restrict the vacuum advance running ported vacuum.

Ron B.C · 05-13-2020, 07:05 PM

Quote:

Originally Posted by Brob

I did the AIR and EGR delete when I installed the Edelbrock Performer 2.0 manifold and freshly rebuilt Quadrajet.

Would love to get it cleaned up that much Brob!, but I have dumped double the budget into the rest of the MH and still going, so for now ill have to keep the stock stuff.
If I can ask...on the diagram if someone could list what lines do i need to keep?
egr to....port?
Vacuum advance to what port? on the carb or the thermostat vacuum line?
Can the other EFE stuff be disconnected and plugged?
Thanks for all the help, this plate of spagetti had me discombobulated.

(oh how I miss my old 350...1 line to the vacuum adv and a pcv that was it)

EyezOpen · 05-13-2020, 08:46 PM

Quote:

Originally Posted by Ron B.C

Would love to get it cleaned up that much Brob!, but I have dumped double the budget into the rest of the MH and still going, so for now ill have to keep the stock stuff.
If I can ask...on the diagram if someone could list what lines do i need to keep?
egr to....port?
Vacuum advance to what port? on the carb or the thermostat vacuum line?
Can the other EFE stuff be disconnected and plugged?
Thanks for all the help, this plate of spagetti had me discombobulated.

(oh how I miss my old 350...1 line to the vacuum adv and a pcv that was it)

OK take a picture of your engine bay maybe a few...don't let that spaghetti mess intimidate you...Aside from the distributor.. all points don't give a hoot where they get there vacuum from...So just start hooking things up..you will need a few tees to bridge more than a few lines.

Yes the AIR system can be cut off..disabled and plugged..if your home state allows those mods. It very simple.

Ron B.C · 05-16-2020, 03:58 PM

I wanted to say a big THANK YOU to all that have helped, not only on this issue but the others I have posted.
With all the help I have fixed my charging issue, have headlights that now work, finally received the plugs that were suggested for the exhaust manifolds to plug the AIR holes and installed them, have the vacuum line spagetti factory sorted out ( still going to play around with it a bit more) but fired the beastie up and its running pretty smooth.
Now on to the next thing!

Brob · 05-16-2020, 06:35 PM

That's really great to hear; thanks for the report.

I know after I went through all of those things, when I finally got it all sorted out, it felt so good to turn the key and hear the 454 purring like a kitten.

Have you taken it out for a test run yet?

Brob · 05-16-2020, 06:42 PM

Quote:

Originally Posted by EyezOpen

Yes, there is quite a benefit to recurving the dizzy..question here did you limit the vacuum advance to 10 inches on the vacuum advance can? If you set the initial at 12 and then advance 22 degrees mechanically then one should restrict the vacuum advance running ported vacuum.

Actually, after playing around with it a bit, I ended up at 10 degrees advance. I tried it at first at 12, but it just ran and idles better at 10.

EyezOpen · 05-17-2020, 12:51 PM

Quote:

Originally Posted by Brob

, after playing around with it a bit, I ended up at 10 degrees advance. I tried it at first at 12, but it just ran and idles better at 10.

Same here static at 10 degrees...22 mechanical advance that's 32 all in at about 2000 rpm. I've used a crane vacuum can to limit the vacuum to 7 inches for rpm levels below 1500 rpm...or when there is vacuum present which is only present during cruise or idle...Pretty slick little kit below i cannot imagine what they would have been worth 35 yrs ago...

https://www.summitracing.com/search/...tor-type%3Ahei

Ron B.C · 05-31-2020, 07:34 PM

1 little thing I just ran into, I was putting my dash back together and hooked the vacuum line back up to the gauge. Started it up and had the needle hovered at about 20. Stepped on the gas and it does a quick drop in vacuum then jumps up between 20 an 30 as I hold the idle up. So I will get batter gas mileage the more I step on the gas right?...