ENGINE TIMING

[Duke W.]

Re: 63 vacuum advance

We've had discussions about this before, and I said that the 1116163 VAC is a boat anchor. I do not recommend it for ANY Corvette engine, even the base cam engines. The B1 ID is correct for aftermarket replacements that match the 163 spec, but this specification VAC was never used on a production Corvette engine.

Unfortunately, at some point, GM consolodated a number of OE VACs with a single replacement part number and chose the 163. Bad choice! And since the aftermarket keys off the GM replacment part number, that's why the "B1" VAC get purchased by a lot of unknowing Corvette owners.

The 1115201 is very rare because, if it was available through service parts, its life span was short. It was discontinued from service parts even when it was OE on the L-71.

I don't recall the construction details of the 201 on my 327/340 as I disposed of it 40 years ago when I replaced it with the 1116236 8" VAC to solve the idle stability problem, but I see no reason why it would be constructed any differently than other VACs of the era.

At this point in time an original would certainly have a "patina" from 40 years on the engine. I have seen a few.

Duke

[Duke W.]

Re: GM solved the "run on"problem with a

That was on later emission controlled engines. Since they had very little total idle timing and higher idle speeds than pre-emission engines, run-on because a serious customer sat. issue.

My '72 Vega GT had one of those idle speed solenoids.

Duke

[Clem Z.]

they could be adapted to early models

to solve the run on problem

[John D.]

Re: ENGINE TIMING

Hey Duke, I give up. What's an ITALIAN tune up???? Is this a personal joke or something. Are you Italian. Or are u referring to JL or JD or what. I haven't heard that slang used before and like stuff like that. RJ did you hear that???

My Vac adv on my showcar is a really old one for sure. Don't know how the thing is still workin but it is. You can have those things rebuild you know. TI Specialites has them done over and they do a very nice job. Takes a while and not cheap but worth it for a rare part.
Only thing a B1 is good for is parts to restore other vacuum advances. I probably have a dozen or so new ones around here. Used to sell them until I found out they were the pits. It's so unfair some of the stuff we bought over the years in good faith for good money and got it where the sun don't shine. John

[Duke W.]

Re: ENGINE TIMING

"Hey Duke, I give up. What's an ITALIAN tune up????"

Take it out and run the pi** out of it! Blow out the carbon.

I remember a couple of times on my '63 when I took it out for some 130+ MPH blasts - when I backed off I was leaving a trail of hot, glowing embers - scared the sh** out of me thinking I had done some damage, but the L-76 was fine. The glowing embers were probabay just carbon deposits from the cylinders and exhaust system being broken loose and expelled by the high volume, speed, and extreme turbulence of the combustion and exhaust processes.

I'm quarter Celt (Welsh, the source of my surname) quarter Anglo-Saxon (English) and half German. That's probably why I'm so independent and stubborn and why I have to be chained to a tree when I watch the barefoot, dancing fiddler from Celtic Woman.

Duke

[Verle R.]

Re: ENGINE TIMING

John,

An Italian tune up is....take it out and drive the crap out of it, also known as blowing out the carbon.

Around this part of the country we called it other politically incorrect names.

Verle

[John D.]

Re: ENGINE TIMING

What you don't learn on this technical board. Amazing. I will put info to good use. Thanks Duke and Verle. John

[Mark #28455]

repro L88 solenoid works well

for all BB rect port high rise intakes from 1965 to 69. May work on oval ports too if high rise?
Mark

[Joe C.]

Start with a GOOD grade of...........

extra virgin olive oil, maintain a constant engine speed of 2000 RPM, & pour it down the primary throttle bores, in a steady stream. This will form an emulsion. Marvel Mystery oil or "hooch" can be substituted by those of northern European extraction.

This procedure is similar to that in which water is poured down the throttle bores to dislodge and remove excess carbon from the CC's. Have a trusting friend stand opposite the exhaust outlet to log the carbon chunks, flotsam, embers and aluminum bits emanating from the tailpipe.

Good night, and good luck!

Joe

[Alan S.]

Re: ENGINE TIMING

Duke,
I'm so glad to read that someone else has noticed the 'dancing fiddler'. In the East we only get to see her during fund raising. I guess PBS has us figured-out!
Regards,
Alan

[Duke W.]

Re: ENGINE TIMING

Buy the DVD(s). I'm probably going to wear mine out!

Duke