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Discussion Starter #1
Engine is 1966, 289-2V with a Holley 2 Barrell and a Crower PN#15915 camshaft. It delivered 200.5 HP on the dyno when tested after the rebuild and before being installed.

The cam spec. shows 258 degrees duration on the intake and 264 degrees on the exhaust. Intake opens -6 ATDC and closes 30 ABDC. Exhaust opens 41 BBDC and closes 11 BTDC.

Engine seems to be rougher than my stock '65, but also seems to have more acceleration.

I am concerned that there may be a plug problem or something else that occured between the dyno test and having the engine installed in the car and running. Any help appreciated.
 

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15915 258° 264° 202° 208° 0.440''0.445'' 112° 1,200 – 3,800

What's the CR? With your camshaft, that will have a bearing on idle quality. Also, the big Holley two barrel might need a little tweeking, depending on throttle shaft position.

Are you running PCV? If so, where does it hook up?

Ignition system type?

What is the total advance? Idle advance? Any detonation at WOT on the dyno? In the car?

IMO, your engine should idle at or near stock rpm and smoothly.

Get back to us....
 

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Not sure what CR is. Holley is a really stock 2 BBL with nothing special. From what you say, I probably should put in a new set of plugs. The distributor has an adaptor and the high voltage cap along with the blue MotorSport high voltage wiring. Thanks again for all the help. Will do the plugs first as they are most likely what got damaged in the installation. It ran great on the dyno and I don't remember it being rough at idle as I stood behind the bullet proof glass and watched the tests.
 

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Discussion Starter #5
Engine should have low compression pistions to run on 87 octane unleaded. This is supposed to be a really tame unit for SWMBO for general grocery getting and occasional highway driving. Thanks again for the help.
 

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CR = compression ratio....higher compression counteracts, to a certain extent, the reversion present at idle which is caused by the overlap of the camshaft. Lower compression and reversion = lopey idle.

Your cam has only a small amount of overlap so this shouldn't be a problem but can become noticeable if the CR is low enough.

While you experiment, be sure to log any original settings/components and what you've done. That way, you can always return the engine to the tune state which existed when you dyno'ed it.

Good luck!

Edit to add I see you figured that out! *G*...If you've got a CR under 9:1, any inefficiency at idle will be more noticeable with the cam you're using, as opposed to totally stock cam. Are your pistons dished or do they just have some little eyebrows for valve reliefs? The dished ones are lower CR...
 

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Discussion Starter #7
Since I did not personally assemble the engine I am not sure about the pistons, but the instructions were to set the CR so it would run on 87 UNL. I will look at the bill to see if the pistons are itemized and get back to you. The engine was rebuilt by Pete Thompson Racing Engines here in San Diego. He has an excellent reputation, but has since retired and the shop is run by an employee who was with him for 14 years. I may ask him on Monday if he knows or has the specs. What would be a good plug to run in this application? Thanks again for the help.
 

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Note your present plug number and, upon making a good WOT run, shut down without extended idling, pull a plug and report the condition of the electrode and insulator; also verify the gap.

Get back to us...
 
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