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Old 05-13-2020, 09:25 AM   #51
vince1
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Join Date: Jan 2013
Location: Calgary Alberta
Posts: 1,162
Re: Stubborn Engine Problem

I thought for a while that you might have cam problems but am glad to see you have it sorted out. With those expensive parts I guess you are way closer to the razor's edge as to how everything needs to be tuned. As for mine the last time I had my OEM HEI apart I put in two spare shiny silver springs to replace the two rusted ones that may or may not have been still holding their tension. That constituted a splurge on my part and I don't even know yet what the timing figures are. I do admire you guys that work at getting good performance out of these engines.
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Old 05-13-2020, 12:41 PM   #52
drew8mc
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Join Date: Mar 2017
Location: Portland
Posts: 63
Re: Stubborn Engine Problem

Quote:
Originally Posted by geezer#99 View Post
Now that it’s electronic, what timing numbers are you running now?
Timing numbers like initial, when does mechanical start and how much, mechanical all in timing and at what rpm.
Startup is 10
idle under load is 16 to 21
Tip in is 16 to 24
Cruise is 25 to 35
WOT is 16 to 30
High RPM, low load is 33 to 40
Decleration (High RPM, high vacuum) is 31 to 40

It's all right there in the chart. Basically it's vacuum on the side and RPM at the bottom and then the timing you are running at where they cross. You can change any cell on the fly and it will automatically fill the next cells so the curve makes sense. So for instance if I wanted 2 more degrees at idle I can set that without resetting any of the other timing numbers. I need to play with a bit more. There may be more timing to put into it at WOT but I want to proceed slowly.

You start by generating that table by inputing some basics. I think my all in advance at 3000 was 32 with another 8 deg of vaccum advance. Idle RPM set at 750.

If I was a drag strip guy, I wouldn't hesitate on buying this thing.
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