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Poor performance after installing new Ignition parts

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Old 11-29-2001, 01:02 PM
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DavidOrr
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Default Poor performance after installing new Ignition parts

Okay, so here's my stupid question for the day.

Several months ago I installed new Accel ignition components 8.8 wires, cap, rotor, and coil on the stock distributor. Since all this has been installed - timing set per factory specs - the car is not up to par. It won't even smoke the tires :confused: . I've played with timing a little, getting ready to play some more, however I was hoping someone had some suggestions.

I've also been reading about Lars KwikCurve Kit, which I think I probably need. Does Lars market this himself or through a distributor?

Thanks
Old 11-29-2001, 01:43 PM
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Tom454
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

Contact Lars direct for the kit.

The forum performance dudes (not me) will need to know lots more about your engine to answer your question. Post everything you know about the engine. Without this info, any answer will just be pyssing in the wind.
Old 11-29-2001, 01:50 PM
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63Banshee
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

The work you listed shouldn’t have changed the performance much… for the better if at all. Did you pull the distributor out of the motor or maybe just lifted it up a bit? Some piece of the puzzle is missing.
Old 11-29-2001, 01:55 PM
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GaryS
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Default Re: Poor performance after installing new Ignition parts (63Banshee)

The work you listed shouldn’t have changed the performance much… for the better if at all. .
Did you double check your work? Timing as per factory specs with the vacuum advance disconnected and plugged; dwell as per the GM numbers (around 30), are the plug wires correctly installed in the following sequence: 18436572? Your missing something here.
Gary
Old 11-29-2001, 02:33 PM
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DavidOrr
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Default Re: Poor performance after installing new Ignition parts (GaryS)

Tom - Thanks

Banshee I agree it should be better. Gary, yup double checked everything, just went over it again this morning. Found two wires that got a little to close to exhaust, so I replaced them. Everything is in the correct order. Distributor was not removed or lifted.

It runs, starts decent, sucks through gas like there's no tomorrow.

I just tried advancing the timing a lot - way off the scale. Ran like a new car. Good acceleration, peep, etc. However, started detonating at idle, so I turned her back to 12 degrees at idle - vacuum advance pulled, plugged, etc. etc. Now shes back to her dog tired self.

I'm not sure what to tell you about the engine, she's a stock L-82.

Bear with me guys I've been in the computer industry to long. I've been looking at Lars papers on timing. At idle, vacuum off/plugged. I've got it set for 12 degrees, if I rev it beyond 3k she'll drop to about 10 degrees. In reading Lars papers on timing, he indicates that the stock springs will not allow full advance until redline. With the stock springs is this normal?
Old 11-29-2001, 03:29 PM
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nunus79
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

I've got it set for 12 degrees, if I rev it beyond 3k she'll drop to about 10 degrees.
:eek: :confused: You sure you set initial timing to BTDC & not ATDC????
Old 11-29-2001, 03:39 PM
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RoyArms
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

if I rev it beyond 3k she'll drop to about 10 degrees.
Isn't it supposed to go up to around 36 degrees for best performance? Even if it isn't tuned perfectly, shouldn't it still go up and not down (meaning >12 deg)
Old 11-29-2001, 04:11 PM
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DavidOrr
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Default Re: Poor performance after installing new Ignition parts (RoyArms)

if I rev it beyond 3k she'll drop to about 10 degrees.

Isn't it supposed to go up to around 36 degrees for best performance? Even if it isn't tuned perfectly, shouldn't it still go up and not down (meaning >12 deg)
Logically I would think that it should go up, however since I'm not always logical :D I put the whole story as to what she is doing. According to the stock timing marks she set to the right place on the BTDC side of things.
Old 11-29-2001, 04:28 PM
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fauxrs
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

if you put a new rotor on - could it be binding up withthe advance weights - all of your advance should be in by 3000 rpm but it sounds as if you are getting none.

I wouldnt think it would be possible for the weights to bind -
Old 11-29-2001, 04:33 PM
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FeedVaal
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

New parts don't necessarily mean good parts.You may have sabotaged yourself with a brand new bad coil. On the other hand, you claimed performance improved when you advanced the timing.I would find the most advanced condition that allows you to turn off the car without dieseling and call that good. I've timed many SBC's by ear over the years and though its not optimal, its good enough for the girls I hang out with.
Old 11-29-2001, 04:46 PM
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nunus79
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

Logically I would think that it should go up, however since I'm not always logical :D I put the whole story as to what she is doing. According to the stock timing marks she set to the right place on the BTDC side of things.
So you are saying this:

you set the initial timing at 12 deg BTDC and as you rev it up the mark goes clockwise down to 10 deg BTDC.

not this:

You set the initial timing at 12 deg ATDC and as you rev it up the mark goes counter-clockwise to 10 deg BTDC.

right?

If right, I'm w/Fauxer.
Old 11-29-2001, 05:11 PM
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Default Re: Poor performance after installing new Ignition parts (nunus79)

Best way to set timing on a SBC is to disconnect the vaccum advance, rev the engine to 3000 and set the timing at 36 degrees. Use a dial back timing light. If your mechanical advance springs are too light, some of the advance comes in at idle and not enough is left for higher rpms.
Old 11-29-2001, 05:38 PM
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nunus79
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Default Re: Poor performance after installing new Ignition parts (simard)

Best way to set timing on a SBC is to disconnect the vaccum advance, rev the engine to 3000 and set the timing at 36 degrees. Use a dial back timing light. If your mechanical advance springs are too light, some of the advance comes in at idle and not enough is left for higher rpms.
Disagree. (1) If your mechanical advance is screwed up you might end up with too much initial advance. (2) If your springs are heavy, you may continue to get unwanted advance after 3000 rpm. ex. @3200=37deg, 3400=38, 3600=39, 3800=40, etc., etc.
Old 11-29-2001, 09:20 PM
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DavidOrr
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Default Re: Poor performance after installing new Ignition parts (nunus79)

So you are saying this:

you set the initial timing at 12 deg BTDC and as you rev it up the mark goes clockwise down to 10 deg BTDC.
Yes this is correct.

I indicated earlier that I advanced the timing way off the scale and it ran much better. This was done the way simard suggest, per Lars instructions as well just without the right springs. Pulled vacuum, dialed timing light to 36 rev'ed to 3000 and set to 0 on timing scale. Had better pep, acceleration, etc. Hard to start and began to detonate at idle. Lars also suggest to when doing this to recheck the timing at idle and this becomes your new set point. Problem is that at idle I'm way off the scale.
Old 11-29-2001, 10:02 PM
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Default Re: Poor performance after installing new Ignition parts (DavidOrr)

So this condition exists "(1) If your mechanical advance is screwed up you might end up with too much initial advance. "

Your mechanical advance is not working properly (stuck), as Fauxrs said.

I recall reading Lar's instructions awhile ago & I think you are misunderstanding the 36 deg at 3000 rpm thing. Lars wouldn't say something like that UNLESS 36 degrees was the MAX mechanical advance amount that the distributor produces. Lars????
Old 11-29-2001, 11:06 PM
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micks69
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Default Re: Poor performance after installing new Ignition parts (nunus79)

You said you put in new cap rotor points etc... right? Did you set the dwell with an analog gauge? I did with two of them and when my neighbor checked it with a digital it was at 17 deg. not the 30 I thought. Same symtems car ran like my wifes windstar! Then cabooiee! It ran like a vette.
Old 11-30-2001, 08:16 AM
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DavidOrr
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Default Re: Poor performance after installing new Ignition parts (micks69)

You said you put in new cap rotor points etc... right? Did you set the dwell .....
HEI - no points, no dwell, just timing - like the Windstar.

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