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Discussion Starter · #1 ·
Finally have a house and a few minutes to play with the 66 Chevelle. Took it out Sat, went a mile, and ran out of gas. My fault. Walked home and got the trailer. Second time on the trailer, in the last 3 trips...

Still, overall, it starts poorly after 10 minutes of running, and still stalls when put in gear. Overall, it runs very poorly.

I looked at the HEI power wire, and noted it was twisted on to a green wire from the harness. So I soldered it, installed a new neg bat cable, and cleaned up the ground connection. Turns over a bit better.

Is the original wire from the harness big enough for the HEI, or should I rewire it from the key, or put in a relay? The previous guy swears it is wired for 12 v full time, but I didn't check it yet.

And where should the timing be set? With the base timing apparently set at 8-10, it won't idle in gear. With some more advance it will idle a bit better. Yes, it has way too much cam and way too little torque converter.

Sorry to sound dumb, but I am not familiar with Chevy small block and wiring, or how this is wired yet, and the manual does not help much yet. Think I have a long way to go...

Thanks for the help.
 

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There are a lot of hei configurations out there.Most need around 12-14 degs. initial toget proper total of 34 or so. the proper vacuum advance is important, many have to much adv. and come in to early.One for alate 70's L82 vette works well .Use of man. vacuum to the adv. should help your idle.Check voltage while running at the plug. Should be 14-15 volts.
 

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Plug should have at least 12v,, the converter has nothing to with idle in neutral. Have you been reving it up lately? Check the Adv. springs under the rotor cap. I have seen them get thrown out and mess your timing up. Hope you get it,,,
 

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the factory power wire has a coating on it. i can't remember the correct name for it,but that wire is made to loose volts at it's original length. it needs to be cut back in length to get 12 volts out of it. i know someone here has more info on it than me.
 

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Discussion Starter · #5 ·
Thanks. So far I am just trying to get this thing civilized enough to drive around. It apparently has a significant cam, as it has 12-16 in of vacuum at idle, at most, and the vacuum fluctuates steadily, and a stock converter.
It will idle fine and stall when put in gear, unless the timing is way more advanced than I am used to. My guess is that the cam is maxing out the valvesprings. The two wire twist ignition was a surprise find.

It also has an Edelbrock 1406 carb, with which I am not familiar either.

I will get there.

This thing gets lots of looks, even without any trim installed!
 

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You need to change the power wire that's coming from the bulkhead connector to the HEI. The easiest way to do it is to buy the L00510 wiring kit from Year One. It has the correct connectors on both ends for easier installation. Do this first, then chase the other gremlins. JMO, based on experience.
BillL
 

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It is common that as the cam timing is increased more idle timing advance will be needed. How to accomplish this varies depending on the "expert" :)

You can try an expirement and gradually advance the timing to see where it idles best (but put it back right before driving it). This will give you some rough idea of what the engine likes.

Next set the total timing to 36* with the vacuum line to the advance disconnected from the advance and plugged. See where your initial lands. If it lands in the 16-18* range that is pretty good. If you advance too much beyond that you can start to have too much advance at engine cranking speeds.

Next if you need still more advance at idle you can tune the vacuum advance. First if you have 36* total, you want 14-16* maximum advance from the vacuum can. Many provide 20* or more and will need a limiter to reduce this. You can buy or make something to reduce how far the advance rod can move. Then you want a vacuum advance that is all in at 1-2" less vacuum than you have at idle and connect it to the manifold vacuum port. This will give you close to 30* advance at idle and really makes a bigger cam happy.

Although your vacuum is not really that bad.
 

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Discussion Starter · #8 ·
Thanks, I ordered the HEI wire. The stock wire seems tiny for an ignition, but my yardstick is 25 years of small block Fords and a Jeep here and there. This will have a Duraspark soon if it doen't get better. Not really. I am trying to go at this slowly, and change as little of the remaining original stuff as possible. I think I will pull the underhood harness from the bulkhead connector and clean it up, and check it out. It seems to be starting and idling better right now.

I set it at 10 to 12 deg initial advance. With the vac can hooked up, its got a lot of advance at idle, but it works. My sbf toy is set at 6 base, no vacuum, and 26 mechanical. It will run fine and start ok at 8-10, but no more. I pulled the vacuum off and backed it down to spray it. So I thought more than 8 was too much. So far the 350 seems ok with much more base timing than my carbed 302's want.

Next up is to install some lock cylinders for the doors and trunk. Probably install some of the grille and rear panel trim!

Then cut the front springs and get it aligned.

Then we have a beginning driver!
 

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my Nova had about 18 degrees initial timing, with 16 degrees of vacuum advance hooked up to manifold vacuum. i set the timing to 34 degrees total.
it would idle silky smooth at 800 rpm with 16-17" of vacuum, got 17 mpg at 70 mph (3500 or so rpm's) with 3.7 gears and 26" tires, and started up right away every time.
this was with 10:1 compression, vortec heads, and the GMPP HOT roller cam that has .525 lift and plenty of duration.
i kind of miss that motor...
 
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