The Ford Barn

27lizzie · 03-29-2016, 10:28 PM

I am using a chev HEI dist with Vacuum advance in my 8BA. Would this set-up use ported or manifold vacuum ? Thanks Marlon

wga · 03-29-2016, 10:58 PM

Manifold

WestCoast · 03-30-2016, 12:07 AM

ported, coming from the carb port, the port above the throttle plate, that way it only has vacuum advance as the engine rpms come up, from the manifold the advance will go full advance at idle and drop off as the rpms come up

flatheadmurre · 03-30-2016, 12:41 AM

Quote:

Originally Posted by WestCoast

ported, coming from the carb port, the port above the throttle plate, that way it only has vacuum advance as the engine rpms come up, from the manifold the advance will go full advance at idle and drop off as the rpms come up

What youre talking about is venturi vacuum to me and for loadamatic and OEM carbs only.
Ported to me means you have no vacuum at idle to deal with polution issues and as soon as you go to high idle full vacuum comes in and then work as manifold vacuum.
For the HEI use manifold vacuum !

WestCoast · 03-30-2016, 01:44 AM

mine doesn't it comes from the port on carb above throttle plate, manifold vacuum is for the loadamatic dist, the advance works just the opposite of vacuum advance

34PKUP · 03-30-2016, 03:53 AM

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Quote:

Originally Posted by WestCoast

ported, coming from the carb port, the port above the throttle plate, that way it only has vacuum advance as the engine rpms come up, from the manifold the advance will go full advance at idle and drop off as the rpms come up

Quote:

Originally Posted by WestCoast

mine doesn't it comes from the port on carb above throttle plate, manifold vacuum is for the loadamatic dist, the advance works just the opposite of vacuum advance

Can't figure out what any of this nonsense has to do with running a "chev HEI dist with Vacuum advance"

Charlie ny · 03-30-2016, 05:24 AM

I'm sure Flat Jack or Bubba will weigh in here soon...........they will say manifold vac.
as do I !

Charlie ny

JWL · 03-30-2016, 05:41 AM

I'm not either of those mentioned but manifold vacuum should be used with the HEI. The reasoning is thoroughly explained in my book.

JWL

JSeery · 03-30-2016, 07:32 AM

Quote:

Originally Posted by WestCoast

mine doesn't it comes from the port on carb above throttle plate, manifold vacuum is for the loadamatic dist, the advance works just the opposite of vacuum advance

This is not related to the HEI, but the load-a-matic does not use manifold vacuum (or ported vacuum either for that matter), it requires a specific carb designed to work with it.

Ol' Ron · 03-30-2016, 09:22 AM

JWL X2. Plus it can be used with any carb combo,

Bruce Lancaster · 03-30-2016, 09:43 AM

Stock passenger car HEI cans have WAAAY too much advance, as they were used with EGR. usually # of degrees is stamped on the bracket holding the can. Heavy trucks got a can that is right for non-EGR chevies and aftermarket ones are also available. You'll probably be tinkering and blocking some of the travel anyway, so no big, but don't try to run one as is with the huge vac travel!

03-29-2016, 10:28 PM	#1
27lizzie Member Join Date: Aug 2014 Location: Victoria B.C. Canada Posts: 53	hei dist vacuum advavce vacuum source I am using a chev HEI dist with Vacuum advance in my 8BA. Would this set-up use ported or manifold vacuum ? Thanks Marlon

03-29-2016, 10:58 PM	#2
wga Senior Member Join Date: Jul 2010 Location: Yorba Linda, CA Posts: 962	Re: hei dist vacuum advavce vacuum source Manifold __________________ Henry Ford designed the flathead without the aid of a computer.

03-30-2016, 12:07 AM	#3
WestCoast Senior Member Join Date: Sep 2014 Location: oroville calif Posts: 892	Re: hei dist vacuum advavce vacuum source ported, coming from the carb port, the port above the throttle plate, that way it only has vacuum advance as the engine rpms come up, from the manifold the advance will go full advance at idle and drop off as the rpms come up

03-30-2016, 01:44 AM	#5
WestCoast Senior Member Join Date: Sep 2014 Location: oroville calif Posts: 892	Re: hei dist vacuum advavce vacuum source mine doesn't it comes from the port on carb above throttle plate, manifold vacuum is for the loadamatic dist, the advance works just the opposite of vacuum advance

03-30-2016, 05:24 AM	#7
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	Re: hei dist vacuum advavce vacuum source I'm sure Flat Jack or Bubba will weigh in here soon...........they will say manifold vac. as do I ! Charlie ny

03-30-2016, 05:41 AM	#8
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: hei dist vacuum advavce vacuum source I'm not either of those mentioned but manifold vacuum should be used with the HEI. The reasoning is thoroughly explained in my book. JWL

03-30-2016, 09:22 AM	#10
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,985	Re: hei dist vacuum advavce vacuum source JWL X2. Plus it can be used with any carb combo,

03-30-2016, 09:43 AM	#11
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: hei dist vacuum advavce vacuum source Stock passenger car HEI cans have WAAAY too much advance, as they were used with EGR. usually # of degrees is stamped on the bracket holding the can. Heavy trucks got a can that is right for non-EGR chevies and aftermarket ones are also available. You'll probably be tinkering and blocking some of the travel anyway, so no big, but don't try to run one as is with the huge vac travel!