Re: Cured a problem.

["T. S. White" <tswrace@pacbell.net>]

For all of you that responded I will detail the process.  When I first 
installed the new engine I worked for days trying to get the fuel 
mixture right.  My headers were getting red hot at idle.  I thought this 
indicated a lean condition but if I increased the jet size on my Holley 
600 the headers would get even hotter.  I was measuring temps with a 
lazer thermometer.  Also, if I increased the jet size the plugs would 
load up after a few minutes at idle.  I settled on size 56 primary jets.

The engine would run OK on the 56 jets and the engine temperature was 
stable at about 195 degrees.  Anytime in traffic would drive the temp up 
over 200.  The heat coming off the headers would make the passenger 
compartment uncomfortable at low speeds.

I had a problem with the fuel preasure during the above process.  I 
would adjust the preasure at 5 1/2 pounds at idle.  After taking the car 
for a drive the fuel preasure guage would read 0 - 2 lbs of preasure.  I 
would re-adjust the fuel preasure to 5 1/2 lbs.  After the re-adjustment 
when I started the car cold the fuel preasure guage would read 9 - 10 
lbs.  After it got hot it read 5 - 6 lbs.

I called the Holley Tech Line.  They said that the liquid filled fuel 
pressure guage I was using had problems working in high heat 
environments.  They recommended that I switch to the non-liquid filled 
guage.  I switched guages and adjusted my fuel preasure to 5 1/2 lbs. 
The engine immediately relaxed.  I reset the carb fuel bowl level at 
this point for the new fuel pressure.  I left the size 56 jets in the 
primaries.  However, the operating temp remained the same.  Holly also 
said they would have my engine on size 58 primary jets.

Last weekend I was adjusting my valves and decided to look at the plugs. 
 I installed new plugs about 600 miles ago.  The plugs looked good in 
general but the electrode was still too white for my taste.  An 
indication the engine was lean.  On a hunch that the previous problems 
with header temps were a result of the fuel pressure problem I increased 
the size of my primary jets to a 57.  The engine immediately relaxed 
again.  I re-tuned the carb for the new jets.  The engine operating 
temperature dropped 10 degrees.  The headers cooled off considerably. 
The engine will idle for an extended period before the plugs begin to 
load up.

For reference my engine is a 289 Ford bored and stroked to 306.  It has 
a 10:1 compression ratio.  The heads are ported and polished.  It has 1 
5/8" custom headers.

It is on stands now as I prep for Triumphest but I can't wait to get it 
off stands and drive it with the new jets.
	Best Regards,
	Tom

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