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Discussion Starter #1
Guys, I just rebuilt my carb (maybe some of you saw the post) , but anyways I wanted to try to get my engine adjusted a little better than before. After reading a few posts on timing it seems that 8*-12*btdc is a good start. After adjusting my idle mixture with a vacuum gauge(reads 17hg),its about 2 turns from being seated. Then I put a timing light on it. This is the first time I checked it, but in the past, the car would seem to ride fine cruising, but when you jump on it , it would seem to load up and blow out some dark brownish smoke. Well the reading I got at idle was at 18*btdc, so I reset it to 10*, rechecked the idle mix. and took a ride. The car does run better, but doesnt respond great jumping on it. But it doesnt load up like before and blow smoke. It seems also that the temp is a little higher now. Before the car ran at 180 cruising, now its at 190. Does the timing somehow effect that to? The car seems to shift into 2nd a little sooner than before also. Is that affected by the timing change also? How to I know where the optimum timing setting would be? Is it by trial and error? What will going too far in either direction result in?. Im just trying to get it close to the best position that I can. I do not have a tach, so I cant say where the timing is at other rpms. Will a change in the timing change that hesitation when I hit the gas, or do I need to change the nozzle in the carb? Looking for a few pointers. But I will admit, the car is running better.:) And I feel it can do better. Do I need to get a tach, to truely get the most out of the timing? Its a 283, Holley 600, Edlebrock performer intake,Mallory9000 dist (which the tech sheets say it has 24* of advance), and headers. The internals for all I know, are stock. Thanks in advance!:)
 

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Bump it back to 18deg and limit it to total of 36 to 38.

Last time we had a track rental my dizzy must have been loose cause my 1st pass off the trailor it only went a 12.50 something at 110mph.

This was also without the "1 open spacer. After I puked I checked the timing and it was at 12 deg.
So I bumped it back to 18 and reinstalled the spacer and presto 11.90's/114mph.

Same carb and jetting.
 

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I would set it at 14 and see how she runs...I bet it will be more responsive.total timing should be 34-38 at 3000 rpms.ps make sure you have the vacuum disconnected and plugged at the carb when setting timing.bm
 

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I would set it at 14 and see how she runs...I bet it will be more responsive.total timing should be 34-38 at 3000 rpms.ps make sure you have the vacuum disconnected and plugged at the carb when setting timing.bm
Good catch BM!

I forgot to mention the vac advance cause I don't use it.

My bad!
 

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Discussion Starter #5
I would set it at 14 and see how she runs...I bet it will be more responsive.total timing should be 34-38 at 3000 rpms.ps make sure you have the vacuum disconnected and plugged at the carb when setting timing.bm
I will give it a shot. If I would of done my math, I should of come with 14. Also, I dont have any vacuum on the carb to disconnect. That is, to the dist. Thanks for your advice! BTW, Is the temp somehow affected by the change?? Or was it higher from me beating on it more than before?:D
 

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Yes, usually the more initial timing you put into it the hotter it will run.
That's not true. Retarded timing runs hotter. Advancing timing runs cooler...up to the point of peak efficiency. Once you go beyond that the pressure on the rising piston has negative effects on power and durability.
 
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