Timing? Carb?
Thread Starter
Instructor
Joined: Jun 2005
Posts: 156
Likes: 0
From: Liverpool NY
Timing? Carb?
I have a freshly built 406 and am having an issue with heat....the headers are getting quite hot and beginning to glow when I hold the throttle at 1500ish for 20 seconds or so.
The builder says to set the static timing at 8 degrees advanced with an all in at 34 degrees. The problem was worse before I leaned the carb out (edlebrock 750) but it is still happening.
The builder says I have a carb problem and should consider changing to a Holly 750...does anybody have any thoughts on this?
could I have the timing too far advanced? not far enough? should I consider the carb suggestion?
The builder was highly recommended and knows his business, but I never had this problem with the carb before...
any thoughts?
The builder says to set the static timing at 8 degrees advanced with an all in at 34 degrees. The problem was worse before I leaned the carb out (edlebrock 750) but it is still happening.
The builder says I have a carb problem and should consider changing to a Holly 750...does anybody have any thoughts on this?
could I have the timing too far advanced? not far enough? should I consider the carb suggestion?
The builder was highly recommended and knows his business, but I never had this problem with the carb before...
any thoughts?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
IMHO, you're running too short on timing. 36* by 2800-3000 total and let the initial fall where it wants to, provided you have a decent curve built into the advance. Usual cause of red headers is retarded timing, really lean, or big load for a long time. Maybe jump up a couple of sizes on the carb jets.
Racer
Joined: Oct 2006
Posts: 412
Likes: 1
From: St. John's Newfoundland
Hey FScott.
I'm not sure if I can be off much help here. I have a newly built 383 stroker. I have played with my timing from 8* to 16* initial and 36* all in @ 28-30000. I have hooker s.s. headers and side pipes. I have not noticed any extreme heating. My tubes are starting to turn a golden bronze. I am runing a holly 770. The engine still need some tuning but no extreme heat in the exhaust.
Clyde
I'm not sure if I can be off much help here. I have a newly built 383 stroker. I have played with my timing from 8* to 16* initial and 36* all in @ 28-30000. I have hooker s.s. headers and side pipes. I have not noticed any extreme heating. My tubes are starting to turn a golden bronze. I am runing a holly 770. The engine still need some tuning but no extreme heat in the exhaust.
Clyde
Racer
Joined: Oct 2006
Posts: 412
Likes: 1
From: St. John's Newfoundland
burning exhaust in the headers would definetly cause some hot pipes.
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From: Sierra Foothills CA
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
I had the same problem when my initial was set at 8°. Headers were glowing red at idle.
Now my timing is 16° initial ( 37° total ) and I also use vacuum advance hooked to intake manifold ( NOT ported vacuum on the carb ).
That gives me 15° more advance at idle and it runs great.
37° + 15° = 52° at part throttle is fine
Drifting
Joined: Nov 2002
Posts: 1,951
Likes: 1
From: Shore NJ
IMHO, you're running too short on timing. 36* by 2800-3000 total and let the initial fall where it wants to, 'provided you have a decent curve built into the advance. Usual cause o red headers is retarded timing, really lean, or big load for a long time. Maybe jump up a couple of sizes on the carb jets.
Don't worry about the initial as mentioned above, set your 36* so it's in between 2500-3000, that's the best way to set your timing...you can jump 2 sizes on your jets to see if it is a lean condition, and check your plugs, what are they telling you......
