What can be learned from this.
The idle is set at 1000 -1100 rpm
Running 87 octane. Turn key off after a 15 min drive and 6 times out of 10 it'll diesel for 1.5 - 2 seconds. Shutting off in gear 1 out of 10 times.

Running 93 octane. Turn key off after a 15 min drive and 2 times out of 10 it'll diesel for 1 - 1.5 seconds. Shutting off in gear almost never diesels.

What can be learned from this besides run 93 octane and always shut off in gear and maybe lower idle rpm?

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

What it shows is that higher octane fuel is less prone to detonation or self-ignition. Deiseling is nothing more than the engine continuing to run because the incoming fuel is self-igniting. Lower RPM ( transmission in gear ) tends to reduce it. A throttle solenoid to completely close the throttle plates will eliminate it.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Your idle is too high. Its probably too rich and stinks....

Tie the thing down and tune your idle systems. This may include timing , idle mix , throttle opening, choke, valve lash and voodoo stuff.

I start by lowering the idle enough to just stay running in neutral.....

Lean idle mix till it stumbles......( dont you have a wideband?...) enrich 1/4 turn.

repeat with vacume gauge

repeat without vacume advance.

repeat with initial advance changes.

Repeat in gear

Your problem will be solved.

You may find several things and create one more

Make sure you untie it down before WOT testing.

(others will do this with various teechniques....this is just what I do when I haven t reverted to hacking)

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Yeah....Im the one who destroyed this rare, vintage automobile.....

It won't idle below 1000. I've got 13 in vac and anything below the`1000 the vac drops rapidly and the wide band goes lean no matter what i do with the carb. There just isn't enough vac below the 1000 rpm to pull fuel from the carb.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

What is the initial timing set at?

Higher timing will also make a crisper shut off.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

intial timing is set a 23* total (26*) in at 3000.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir