No vacuum leak, measurements are good, so that leaves centerline or retarded cam as The Zilla mentioned a few posts back: Scope of this project is to get better idle vacuum, and seal up some oil leaks that any 20+ year old engine build has. Next a little freshening of the transmission is going to take place, primarily fixing a flare-up on 2-3 shift once fluid is warmed up, and pump rebuild or replacement. Converter drains back in a day or two, but shifts real nice when cold so I suspect a pump problem.

Once that chunk of iron is off its mounts I’ll put the degree wheel on and check cam advance or retard condition. Expect a few queries on the use of the degree wheel.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Oh, how is the dist mech advance set up? That can cause erratic idle - bigtime.

Lou

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Home of Slant6-powered fun machines since 1988

No advance until 1600 rpm. I found this helped pull timing back to static, and hold it when engine went into its lope. Lately at current idle mixture, power valve, and black magic the engine has been for the most part idling down after coming to a stop predictably not needing feathering of throttle to recover from a extra slow lope cycle. I still knock it into N at lights as the lope sucks gas and is annoying to me. Probably dipping into enrichment circuit, but Holley tec says no not at idle... It really likes to idle at 1000 to 1100 rpm where vacuum is 10 to 12 Hg... Don't recall exact number as I have adjusted and frigged so much with that idle circuit. Lets just say it is into low double digits.

I can say this, when idling in gear tack runs up and down a bit less than 100 rpm say 750 being average, and A/F gage swings rich to lean in time with the lope. o2 sensor is mounted just aft or front collector about 28 inches from head's port. As I said before I can't figure out if rich condition starts the lope, or lean starts the lop. While it is loping in gear timing generally stays stable, but not always and can flutter a degree or two. Currently static is set at about 13* advance, just off the little timing tab on timing chain cover.

The last time I had the distributor apart less than 10,000 miles ago, the governor was moving freely with no binding, and light spring was doing its job.


As I said before there is an occasional hunt or weak fire off of on of the cylinders every 2 or three rotations of engine, and I know it happening from the back three. I can't see a misfire using timing light on 4-6 so I have ruled out ignition. When compression testing I can't hear any hissing from crank case, exhaust, or carburetor indicating valves are seating tightly, so that leaves a lazy sticky valve, or perhaps a lobe erosion problem, or a broken ring.

Once under way 1600 rpm and up, no hunting, or skipping is noticeable.


Can harmonic balancer allow timing to dance around a few degrees if it is in the beginning stages of letting go? Or, do those things just give up and slip 10 or more degrees all at once and stay put?

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Your symptoms sound similar to my EFI DeSoto motor. The cause there is a very worn out timing chain and a slipped ring on the harmonic balance. (timed by comprimise and ear)

This motor has 670,000 kms and uses no oil. The chain has been bad for years. (Dennis and I drove this motor to Lous house years ago and it was bad then)

The idle in gear hunts all over the place....especially with the brakes applied. Once the rpm is up a little the chain tightens up a bit and everything preforms as it should.

Variable valve timing........not always what you want.

A new chain and gears is cheap. .....but I may just put together a new mill......

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

Could be a sloppy timing chain, although this engine has 70,000 miles or less on it since rebuild. With 3.55 rear, and four seasons of racing a chain could be stretched. Car has about 136,000 on it if Mass title paperwork is correct.

I should have the engine out by Monday.

Just to refresh my past reading on engine pulling, one should use the two 3/8th taped bolt holes along manifold top side of head if taking engine & transmission; is that correct?

Should I make some kind of bracket of angle iron bolted to afore said bolt holes to fix a chain to, or just bolt links directly with a few big washers?

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

You want BMEP.

thanks.



I tried researching the 160 ish pressures and it's relationship to detonation and octane/race gas and couldn't find anything on the web.

Got any links?



thanks

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

I have been using mid grade, 89 I think, for a long time. Reason was before adding quieter mufflers, one could not hear any engine sounds, just the racket blowing out the tailpipes. Until now it never occurred to me to try a slug of rotgut 87. Too late now, patient is prepped and almost under the wrench.

A couple of years ago after new muffler fitment while experimenting with main jets I got it too lean, and at that time a hear slight ping could be heard when timing was all in under light tip-in approaching an up grade. A small poke of the throttle would make it go away sending A/F gage into rich zone.

Since jetting up to rich side of factory stock jetting, I think 52 or 53 (that exact info is scribbled in a binder in basement), flat spot coming off steady throttle, and slight ping have gone. Transition through the various stages of Holly Carb are seamless now.

Please define BMEP and IMEP valves. I easily get lost in alphabet soup.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I wonder if you could have significant exh valve recession? Something to eye when it is apart.

Lou

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Home of Slant6-powered fun machines since 1988

I had the now "dreaded hardened seats" installed when head was rebuilt in 2009, 20,000 miles ago.

We'll see though.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Halfway down:

http://en.wikipedia.org/wiki/Mean_effective_pressure

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Well here we go. Got a start on engine pull project Saturday before weekend guests arrived for Dad's 93ed birthday celebration. Some fluid draining, drive shaft removed, exhaust disconnected, some electrical unhooked, and work area arranged.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I found it easier to have the nose down as far as I could get it, with the rear as high as I could get it when pulling/dropping in a motor. Gives ya a better entry/exit angle and whatnot... I know you're a little ways from that yet, but just figured I'd drop a helpful tip

I have always found it easier to pull the engine and trans separately. But to each their own. You will definitely want an engine tilter if you try and get them out together.

I still have some stuff to disconnect requiring my fat gut to slide under car.;~) Then the plan was to get her rear up, and nose down.

I have pulled transmission several times from below, and frankly my old ass just ain't up to the never ending up top to down under repetitions to get after it.

One of those engine tilters is on my list to get.

Monday after cleaning the driveway of snow, hopefully the last such activity of the season, I'll be back under the Dart.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC