Freddie's Transplant

[MacDee]

Do you want Click and Clack's standard answer? Turn up the radio!

Why didn't I think of that...!

[MacDee]

FYI-
I did get a 13/16 wrench and a dial indicator.
The big wrench came in handy setting the motor at TDC.
I never used the dial indicator.

[Luva65wagon]

Gary, That is why I spend so much on stereo equipment!

Sorry I couldn't make it. Just when I thought it couldn't get any worse for me and my schedule it did. And then some. So I hope you can crank up the radio and drive it to a show or two this year.

[MacDee]

I did something Pat told me specifically NOT to do....
Though Freddie has been running pretty well, one thing that has caused me anxiety is that the temp will rise uncomfortably while sitting at idle, as in when waiting at a long stop light.
I was randomly perusing the Ford Six Performance forum and came across this article, one I had read before, I think, a long time ago:

http://fordsix.com/forum/viewtopic.php?f=1&t=63354

The author makes a case for utilizing vacuum advance, manifold vacuum, and claims one of the benefits is cooler running at idle.
I HAD to try it... again.

I re-set my initial timing back to 10 BTDC (it was at about 14), and then... hooked a vacuum line to the MANIFOLD vacuum port.

I'm tellin' you... [Pat...] she runs MUCH better with vacuum advance hooked up! And she doesn't heat up nearly so bad at stop lights!

I had driven her to work a couple of weeks ago, without vacuum advance, and on the way home the temp gauge reached 240 degrees at one point, and I was sweating bullets! Today I took her to the All Ford show at XXX, and she never went above 200 degrees, even on the way home when it was pretty warm outside.

It just seems like the right thing to do.

[ew1usnr]

Hello, MacDee.

"I had driven her to work a couple of weeks ago, without vacuum advance .."

You lost me. Why would you not have a vacuum advance? I thought that all distributers were hooked to a vacuum advance.

Thanks, Dennis.

[MacDee]

Gosh, what can I say?
Ignition timing control over the whole operating spectrum of an engine is, well, a Black Art. Back in the days before electronic engine control systems, it was handled, usually, with a combination of a mechanical method, flyweights working against springs to advance timing as engine speed increases, and with vacuum, working on a diaphragm to advance/retard timing depending on engine load.
With stock production engines, the manufacturers had whole engineering departments working out how best to optimize performance/economy/driveability, and avoid destructive detonation, using mechanical and vacuum inputs into the distributor. With a modified engine, some of the solutions the manufacturer came up with may no longer be valid. Thus, it becomes the hot-rodder's task to "re-engineer" how the distributor responds to engine speed and vacuum inputs. This is why you hear hot rodders talking about "re-curving" distributors, which is changing the way the distributor revises timing based on engine speed.
Vacuum, of course, is another thing to consider. It throws in another variable which can be used, as the manufacturers do, to improve economy and driveability, but with a high-compression modified engine, if not done properly, it can also introduce a factor that can cause damage due to detonation (pinging).
Since vacuum advance gernerally doesn't come into play at wide-open throttle, racing engines typically forgo the use of vacuum advance altogether. In the case of racing engines, you find the maximum total advance your engine can tolerate, then fiddle with the mechanical advance mechanism in the distributor and the initial timing to achieve the optimum performance throughout the rev range without exceeding the maximum Total Advance.
If you peruse this string, you'll see that I've undertaken doing a highly modified 200-inch six-cylinder engine. In hindsight, I bit off way more than I could chew. I've had a lot of trouble getting my engine to run well, and it wasn't until Pat Brown got involved, I'll call him this forum's Primary Guru, that I even got this thing to be driveable at all! He did a modification to my carburetor that turned out to be "The Breakthrough". Among other things, Pat had recommended that, as with a racing engine, I should forgo using the vacuum advance. However, my engine, though highly modified, has a pretty moderate compression ratio. Because of that, I felt it was worth the risk to try to reintroduce vacuum advance to improve some issues I was having that corresponded to those mentioned in the article I referenced.
The result seems to be very favorable. My "overheating-at-idle" problem is greatly diminished, and yet, as far as I can tell, I'm still not having any issue with detonation.

Whew! I hope I didn't bore you too badly.
Thank you for asking!
Are you sorry you did?
(To paraphrase a famous Dr Seuss line, is your brain numb now?)

[ew1usnr]

Hello, Gary.

"Whew! I hope I didn't bore you too badly."

No! That was all very interesting. I have studied carburetors and cam shafts but always took the distributer for granted. I pulled out an engine description for my 260 and verified that its distributer has "centrifugal vacuum advance".

I went back to the beginning of this thread on page 21 and have read so far up to page 15. Wow! You have gone though some struggles. That is an amazing setup, though, with the aluminum head, intake manifold, and custom headers. Jazzing up a V-8 is routine, but I've never read in detail about building a high-performance inline six. That is really cool.

I'll resume where I left off on page 15. It is like reading a novel and I want to see how it ends!

Later, Dennis.