Timing and Pinging nice story (1 Viewer)

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Bonjour,

When I bough my Fiji. I was limited to 2,000 rpm. When I tried to check and adjust the timing, I discovered the distributor was frosted in place. After removal, I discovered a leaking and non-operational dirtributor diaphragm. After reinstallation, I was able to go up to 3,600 but with high fuel consumption.

The original diaphragm had only advance vacuum hose. I found a used Camry diaphragm with advance and retard connectors. I had to surround the diaphragm "washer" with epoxy glue to hold and center it into the distributor's diaphragm hole. All lengths were perfect.

After that, I red about distributor, weight, advance and retard functions. From what I learned, in resume:
- the dynamic timing curve (static timing at idle with weighted rpm correction but no vacuum at all) should follow the maximum power curve when applying wide-open-throttle from idling to top speed.
- The advance vacuum, connected to the manifold, exist to increase fuel economy at part throttle
- The retard vacuum, connected before the throttle, exist to limit advance when cruising.

I installed everything. Settle the static timing at idle. Tried some accelerations without any vacuum hoses to test dynamic timing. Perfect for power. I connected vacuum hoses and I got some pinging when cruising. Tried successively to retard timing but it was so retard that I got no power when idling. Tried differents things without any success.

Eureka: I got the idea to lubricate internal distributor components with some spray with PTFE lubricant (not teflon since when cold, it's too sticky). Vacuums worked great and instantaneously when depressing pedal. No more hesitation and the static timing is set to specification without any pinging, with maximum fuel economy and extreme, yes extreme, low end power. Fantastico.

To conclude: When idling, the advance give enough time to fully burn a/f mixture (smelless). When starting, at zero degree farenheit, the engine launch within 2 turns. It has power and no hesitation. When warmed up, no pinging, no hesitation. Now, that's a very nice engine. (except low compression in #3 and #4 ... resistance is futile ... you'll be assimilated into the perfect world ... I will everlast ...)
 
Salut PO do you know the year of the camry? Did you gain in top speed when change your diaphragm. I have never been satisfied with my top speed on my 71. How can I know if it's working or not.

Merci! :D
 
I have to said that my 2F non-smoged canadian distributor is electronic (with pickup coil).

The Camry was about 1985. May be older or younger. May be it was a Cressida. Does it matter? I brough the 2f distributor, with diaphragm, to the recycling shop and tried to get similar diaphragm. Distributors were different but diaphragm was similar except the holding part/hole. The retaining part which connect to the distributor rotating part was identical in size and length.

My 2F engine is actually revving upto the max HP revs (3,600 rpm) without problem but I am very rarely going upto this speed, nor in 1st or 4th gears.

From what I red, the centrifugal weight correction shall give the proper power timing curve. Upon my tries, running with unplugged and sealed vacuum hose(s) with the spec idle timing shall give the engine's maximum power but low fuel economy. If it's not the case, I would suspect something else.

Actually, I try a sophisticated engine simulator with Harley-Davidson, 3VZ-4Runner and 2F-FJ engines. My first conclusion toward cheap power is "please, breath fresh cold air". My second shall target 9:1 compression instead of 7.8:1, how much grind shall I remove?
 

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