Swapping points/pertronix distributor for HEI question

K

kmorefield

Member
Jan 4, 2020
62
6
8
One more question to the brain trust... I’m in the process of installing Howell efi along with a computer controlled HEI distributor. This
aforementioned computer controlled distributor (HEI) is replacing an old points distributor (that had pertronix installed). I traced a line through
the rotor to the edge of the hatch before I pulled the distributor. I have not rotated the engine at all since pulling the original distributor.
When I install the new HEI CCD unit, do I just need to insure that the rotor is oriented just like the old one was (in the pics below)? So the
question is - if I install the new HEI unit so that the rotor is oriented the same as the original, am I good to go? Or is there some difference with
the HEI that I’m not taking into
account?http://www.gmcmhphotos.com/photos/member-galleries/p68477-points-distributor.htmlhttp://www.gmcmhphotos.com/photos/member-galleries/p68476-distributors.html
--
1975 - 26’ Eleganza II
Unsure of what upgrades may have been done. I'm working on sorting that out in the coming months.
Ken Morefield - Redding, CA
 
Your only half way there.
Need to know as to which piston the pointer isat when you pulled it out,
Best to pull the number one plug and put your finger on the spark plug hole
and crank the engine till you feel the compression.( it is a 4cycles so it
is every other turn)
Then put the cap to # 1 and look at the Harmonic balancer for mark.

On Tue, Feb 22, 2022 at 7:16 PM Ken Morefield
wrote:

> One more question to the brain trust... I’m in the process of installing
> Howell efi along with a computer controlled HEI distributor. This
> aforementioned computer controlled distributor (HEI) is replacing an old
> points distributor (that had pertronix installed). I traced a line through
> the rotor to the edge of the hatch before I pulled the distributor. I
> have not rotated the engine at all since pulling the original distributor.
> When I install the new HEI CCD unit, do I just need to insure that the
> rotor is oriented just like the old one was (in the pics below)? So the
> question is - if I install the new HEI unit so that the rotor is oriented
> the same as the original, am I good to go? Or is there some difference with
> the HEI that I’m not taking into
> account?
> http://www.gmcmhphotos.com/photos/member-galleries/p68477-points-distributor.htmlhttp://www.gmcmhphotos.com/photos/member-galleries/p68476-distributors.html
> --
> 1975 - 26’ Eleganza II
> Unsure of what upgrades may have been done. I'm working on sorting that
> out in the coming months.
> Ken Morefield - Redding, CA
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
The initial setting for the rotor is the same whether it is a points ignition or an HEI. With the engine at TDC 0degrees on the timing mark, and the
and the valves closed meaning the end of the compression stroke. The rotor MUST point to #1 spark plug electrode in the cap.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Guys,

Do you use vacuum to set the Dist to the most vacuum or simply use the hormonic balancer lines?

Take care,
Tom K.
--
Tom & Oki Katzenberger,
Kingsville, Maryland,
1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee
Ignition
 
Sorry, I should have said vacuum to fine tune the Dist.
--
Tom & Oki Katzenberger,
Kingsville, Maryland,
1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee
Ignition
 
There is no vacuum associated with the distributor for fuel injection
Howell systems.
If you are only upgrading from points to HEI, there is still a vacuum
canister on that. Engine idle at 700 rpm has no centrifugal advance yet,
and full vacuum applied to the canister.
Jim Hupy
Salem, Oregon

> Sorry, I should have said vacuum to fine tune the Dist.
> --
> Tom & Oki Katzenberger,
> Kingsville, Maryland,
> 1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control,
> Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee
> Ignition
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
I never use the vacuum method to set riming. Start with spec then adjust from there using real world conditions. Usually this means adding more
advance just shy of the point where tip in pinging starts to happen. However yours with computer control will be a different situation.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
At higher altitude one can power tune it be advancing the timing using the
rule if 1 degree per thousand feet.
I use this rule when crossing the Mountains from California each time on my
Carb unit,

On Wed, Feb 23, 2022 at 5:38 PM John R. Lebetski
wrote:

> I never use the vacuum method to set riming. Start with spec then adjust
> from there using real world conditions. Usually this means adding more
> advance just shy of the point where tip in pinging starts to happen.
> However yours with computer control will be a different situation.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Yes Jim K! I have 3 different colors of scribe marks to indicate sea level, high plains and mountains. Only takes a minute to set with a distributor
wrench cool in the morning before heading out for the day’s drive, based on expected altitudes. Crude, but helps you get back some lost power and
stay cooler pulling the grades.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
John,
I still h.ave the MSD Timing control and use it.
As a Kid in HighSchool, I took my mothers car to drag race and did verywell
as I took advantage of the 5,000 feet.

On Thu, Feb 24, 2022 at 7:18 AM John R. Lebetski
wrote:

> Yes Jim K! I have 3 different colors of scribe marks to indicate sea
> level, high plains and mountains. Only takes a minute to set with a
> distributor
> wrench cool in the morning before heading out for the day’s drive, based
> on expected altitudes. Crude, but helps you get back some lost power and
> stay cooler pulling the grades.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
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