Dumb timing question

[Baker7888]

Definitely a ‘no’ imo.

For performance you only need to be concerned about getting the ‘all in’ as soon as your motor can handle it. And getting the correct amount of timing at your all in rpm.

Everything that goes on below the all in rpm is fuel economy and street manners. Tuning those two are completely separate from performance above 3000rpms. And if you want maximum performance with the best possible street manners, then it will take some fiddling with the dizzy and the carb.

I get a sense from your responses that you don’t want to have it idling at 16-20 degrees? Is that so? If yes, then why?

False. I started at 13 and got my 3000 all in no problem but when bumped to 16 it had great throttle response (in neutral) so i went after getting 16 to work with my total (hence limiter screw). Springs only provided me two options - all in at 2400 (ping city) or all in at 4500.

With no limiter screw i am only 3 degrees shy of 16 base and my all in is at 3000 with no pinging (blue line). Its all outlined in the thread. You answered “no” to my question but your explanation is agreeing with it.

So you are saying all in at the lowest possible rpm is best for performance

Bracket is saying higher initial is always best because of better idle and throttle response

I am trying to get both. The graph shows i can get close but with higher initial i am going to also have a higher rpm for my total.

It may come down to WOT vs spirited cruise driving habits. Which to be honest
I am 100% more interested in spirited cruising versus WOT. Gaining throttle response has my attention.

(I mistakenly thought earlier you had suggested running ported vacuum but you did not so i edited that out of this post)

 

[64nailhead]

False. I started at 13 and got my 3000 all in no problem but when bumped to 16 it had great throttle response (in neutral) so i went after getting 16 to work with my total (hence limiter screw). Springs only provided me two options - all in at 2400 (ping city) or all in at 4500.

With no limiter screw i am only 3 degrees shy of 16 base and my all in is at 3000 with no pinging (blue line). Its all outlined in the thread. You answered “no” to my question but your explanation is agreeing with it.

So you are saying all in at the lowest possible rpm is best for performance

Bracket is saying higher initial is always best because of better idle and throttle response

I am trying to get both. The graph shows i can get close but with higher initial i am going to also have a higher rpm for my total.

It may come down to WOT vs spirited cruise driving habits. Which to be honest
I am 100% more interested in spirited cruising versus WOT. Gaining throttle response has my attention.

(I mistakenly thought earlier you had suggested running ported vacuum but you did not so i edited that out of this post)

You’re not picking up what we are laying down.

You need to give it what it wants, and you have to determine what it wants.

Tuning for performance and tuning the idle/cruise range are seperate and not integrated.

And yes, you might need ported vacuum to get it to idle/cruise well. But that solely depends on how you setup your initial timing.

 

[Baker7888]

You’re not picking up what we are laying down.

You need to give it what it wants, and you have to determine what it wants.

Tuning for performance and tuning the idle/cruise range are seperate and not integrated.

And yes, you might need ported vacuum to get it to idle/cruise well. But that solely depends on how you setup your initial timing.

Nailhead, you said best performance would be getting all in at the lowest possible rpm without pinging right?

 

[Baker7888]

Well anyways, i put the limiter screw back in for one last try. With 1 light and 1 medium spring. If that gets the all in around my predicted 3200 then i guess i’ll just have to go with the seat of my pants dyno. I know that it wont ping at 3000.

 

[Baker7888]

Well guys it stopped raining for two seconds so here it is.

20 initial 36 all in at 3200. Vac can (manifold) adds an additional 20 degrees. Road test reveals no ping, she feels way crisper and smoother, feels like EFI.

 

[bracketchev1221]

Well guys it stopped raining for two seconds so here it is.

20 initial 36 all in at 3200. Vac can (manifold) adds an additional 20 degrees. Road test reveals no ping, she feels way crisper and smoother, feels like EFI.

Congratulations

 

[Baker7888]

Congratulations

Thanks to you all for the help and the conversation. Glad i kept messing with it. Thought when i had it at 3000 that might be all she had. But with the higher initial its noticeably better. The adjustments are sensitive for sure.

 

[64nailhead]

Nailhead, you said best performance would be getting all in at the lowest possible rpm without pinging right?

No.

But I see you have the initial set higher than back a few pages ago and it run much. 20 initial and 36 by 3000 are very normal looking numbers. If it idles and works well off idle to 3000 then great.

Best of luck to you.

 

[Baker7888]

No.

But I see you have the initial set higher than back a few pages ago and it run much. 20 initial and 36 by 3000 are very normal looking numbers. If it idles and works well off idle to 3000 then great.

Best of luck to you.

Is there any way i can check for pinging or detonation, such as looking at spark plugs. I heard that black specks could be present on the porcelain, is this accurate?

I am reading a lot about rattle which i am unsure of how to identify correctly. When i am in the throttle heavy the engine seems to vibrate a lot. I have poly mounts so maybe that is it .. this would be in the 3200 rpm and up range so i know i am all in by this point.

We have a huge hill behind my house so i lugged it up the hill at various rpms, 3200 and below and heard nothing. I can cruise around moderately all day and hear / feel nothing

Wondering if i can identify by looking at my plugs ?? I just dont wanna be mashing on it and detonating oblivious to my attention. …

 

[64nailhead]

Retard the timing 2-3 degrees and see if it changes.