Tonights Adventure...Grrrr
Thread Starter
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Tonights Adventure...Grrrr
OK, so tonight is Break In the Cam night. Fired up great, runs strong. Headers heat up Bright red in about 3 minutes and burn the hell out of 3 plug wires, I shut it down when I got flames.
Should they get that hot that fast?
I got ceramic coated block huggers, base L81 with mild cam, stock carb on a RPM intake and stock ignition
I did not expect that kind of heat
So now what to do about my plug wires??
HELP!!
Should they get that hot that fast?
I got ceramic coated block huggers, base L81 with mild cam, stock carb on a RPM intake and stock ignition
I did not expect that kind of heat
So now what to do about my plug wires??
HELP!!
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
That is "not" unusual for the header tubes to get that hot on a fresh motor. That is why it is suggested, if you have new chrome headers, to use something old for exhaust during break in. (to keep from discoloring the new chrome) Oh...and yeah...replace the burnt wires, restart and then check your timing
Last edited by Jclgodale3; Oct 5, 2007 at 06:33 PM.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Situation normal.....I remember my stock L48 with the TPI on it, and ram's horns, the O2 sensor in the heat riser flapper position....
well one evening/night after a good hard run, I opened the hood in darkness....and the manifolds were glowing orange to yellow, really super hot...well yes, after a good run, HELL yes....easy to turn a piece of steel yellow with a propane torch that engine exhaust can do it to a set of headers in a flash....literally....
what made me pop the hood, was the gray looking appearance of the centers of the ram's horns, the part not fastened to the engine....the runners from the end cylinders....all 4 corner tubes were gray and somewhat stressed looking, but not cracked....looking kinds like they could crack though....3 years later they were still fine.....but you see, a TPI system, or any closed loop runs far leaner than most typical carb setups.....see posts from Norval/Strider about that topic.....
OH, and yes, replace the re do the wire routing....
and welcome to the headers burning wires and plug ends club.... 
well one evening/night after a good hard run, I opened the hood in darkness....and the manifolds were glowing orange to yellow, really super hot...well yes, after a good run, HELL yes....easy to turn a piece of steel yellow with a propane torch that engine exhaust can do it to a set of headers in a flash....literally....
what made me pop the hood, was the gray looking appearance of the centers of the ram's horns, the part not fastened to the engine....the runners from the end cylinders....all 4 corner tubes were gray and somewhat stressed looking, but not cracked....looking kinds like they could crack though....3 years later they were still fine.....but you see, a TPI system, or any closed loop runs far leaner than most typical carb setups.....see posts from Norval/Strider about that topic.....
OH, and yes, replace the re do the wire routing....
and welcome to the headers burning wires and plug ends club....
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
That is "not" unusual for the header tubes to get that hot on a fresh motor. That is why it is suggested, if you have new chrome headers, to use something old for exhaust during break in. (to keep from discoloring the new chrome) Oh...and yeah...replace the burnt wires, restart and then check your timing
Not that unusual. If the headers are new, I wouldn't use them until you've got it fully broken in. That way you can gently break in the headers. Well, maybe it's too late.. 
Even after the engine is broken in and driven for a while, it's not unusual to see the headers glow a slight pink/faint red especially at night when you can see it. I think the low level red color starts at about 800*F.
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Melting Slicks
Joined: Jul 2004
Posts: 2,577
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From: Long Island New York
That is "not" unusual for the header tubes to get that hot on a fresh motor. That is why it is suggested, if you have new chrome headers, to use something old for exhaust during break in. (to keep from discoloring the new chrome) Oh...and yeah...replace the burnt wires, restart and then check your timing
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I used to do that on the way out to a softball game on the highway, at 3500, for about fifteen - twenty minutes. Usually popped my hood to help let out the heat but the headers were never red, even in the failing light of the evening.
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
Thread Starter
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
I think the fuel mix was way off, fried my headers, 2 plug boots and 1 wire. I didn't realize that it would get that hot, was concerened about getting break in done and not the dial in. That won't happen again, $200 mistake!
So, got to order new headers and plug wire set, will go ahead and dial in the carb and valves and then finish breakin
dammit
So, got to order new headers and plug wire set, will go ahead and dial in the carb and valves and then finish breakin
dammit
Intermediate
Joined: Dec 2005
Posts: 40
Likes: 0
From: Las Vegas Nv.
A real good trick on break in is to use an infrared temp gauge and shoot the exhaust while your running.
At a constant between 1500 and 2000 rpm, the temp should not exceed around 1000*.
If it approches this temp, advance the timing just a bit while the car is still running.
It just takes a few seconds to see the temp retreat if the timing was too retarded.
If my new headers approached 1000*, I would want to know it.
At a constant between 1500 and 2000 rpm, the temp should not exceed around 1000*.
If it approches this temp, advance the timing just a bit while the car is still running.
It just takes a few seconds to see the temp retreat if the timing was too retarded.
If my new headers approached 1000*, I would want to know it.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
LOok at them in pitch dark....totally black after a good run...quickly pop the hood, and see them....orange to yellow glo fading fast in steel tubes, takes longer with iron rams horns....and with leaner TPI or any DPFI for that matter running closed loop, it's running hotter yet....
course if you have a set of spals on running, they MAY cool the things down faster than you can get out...but not the iron...that takes a while....
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I believe that, I'm just wondering why the extra heat is common with a fresh build. Is it the extra friction from rings that have not seated and things like that?