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RPM and timing

Yes, that would help. The hardest part is operating the throttle from the engine and watching the timing. Ma Mopar for some reason put timing pointer on other side of engine. So unless you have some crazy long arms, it's not possible to increase rpm and watch timing at the same time by yourself. And I'm a bit of an asshole n opinionated so I don't have any "friend/associates" that I can enlist to help w operating the throttle for me. Hence wanting an idea of what I'm looking for before I recruit a friend from 150 miles away to lend a hand.
I picked up on the asshole thing. You have a pretty bad attitude for asking for well intentioned help from complete strangers.
 
I picked up on the asshole thing. You have a pretty bad attitude for asking for well intentioned help from complete strangers.
Im sorry if I hurt your feelings. My reply that you quoted was not intended to be sarcastic or mean to that poster. However, when I am sarcastic or blunt, it's because someone probably didn't comprehend my original post. Won't say didn't read, but did not comprehend. I do believe the only time I was blunt was with the post about where I should be pulling vacuum. I appreciate that the poster was trying to help, but that is a huge debate that has absolutely nothing to do with what I had asked help on.
 
My 77 360 used to ping on a grade. I always found it better to give it more throttle.
Have you tried it with the vacuum advance unplugged?
You can also adjust the spring tension inside the canister.
Have not tried that yet. Still busy with the truck. Good suggestion though. I did drive the car last night and romped on it enough in drive to downshift n bring the rpm's up to 3,300. Got a little ping and saw that as I did that, vacuum dropped to about 4" and AFR to about 12:1. I'm agreeing w most that I've gotta set it up w out the vacuum 1st, then fine tune the vacuum after. My 1st step is to identify when centrifugal advance "starts" coming in and when it's "completely" in. I'm thinking it may still be coming in a bit early even with the stiffest springs.
 
View attachment 1055706get or barrow one of these pumps, grab some distributor springs and a 3/32 Allen wrench for the can nipple. With the distributor cap and rotor off you can watch the weights and the vacuum.
I think your going to need a little more spring than you have now. If I recall the can adjuster will let you you pull in or out vacuum point a couple degrees each rotation of the adjuster.
I do not remember what direction to turn to go up/ down , just have to mess with it.
Like posted, try pulling a grade with the can unhooked and the hose plugged.
I also read in a linked article that they have different cans with different amounts of advance. Once I have the mechanical advance completely dialed in, then I'll work on the vacuum. I agree though, I think I'm gonna need stiffer springs for my engine build n driving style.
 
Another option is to lock out the distributor and set up the timing in the efi. You can set it any way you like. But pinging at 12.1 afr on a new engine could mean trouble as you get more carbon buildup later on
 
Another option is to lock out the distributor and set up the timing in the efi. You can set it any way you like. But pinging at 12.1 afr on a new engine could mean trouble as you get more carbon buildup later on
The Fitech MeanStreet 800 does not allow computer controlled timing. I bought a little over 2 yrs ago and didn't get the engine running until the end of May this yr. I know little to nothing about programming FI so I went this route. Now I'm kinda wishing I had bought a version that has timing.
 
The Fitech MeanStreet 800 does not allow computer controlled timing. I bought a little over 2 yrs ago and didn't get the engine running until the end of May this yr. I know little to nothing about programming FI so I went this route. Now I'm kinda wishing I had bought a version that has timing.
Any progress with this? I am also dealing with ping. Watching this thread and learning.
 
This might be hard to over come with 10.5:1 compression. Might look at water injection. Snow performance.
 
If you get one of the digital dial back timing lights that shows RPM, it is pretty easy to check haw much advance you are getting at different RPMs, and the RPM when mechanical advance stops (with vacuum disconnected.) Add the vacuum pump noted above and you can see how much vacuum will advance the timing.
I don't have any problem with you running straight manifold vacuum vs. ported, really depends on your setup. The straight manifold vacuum can help idle when running a big cam.
 
If you get one of the digital dial back timing lights that shows RPM, it is pretty easy to check haw much advance you are getting at different RPMs, and the RPM when mechanical advance stops (with vacuum disconnected.) Add the vacuum pump noted above and you can see how much vacuum will advance the timing.
I don't have any problem with you running straight manifold vacuum vs. ported, really depends on your setup. The straight manifold vacuum can help idle when running a big cam.

100% agree with this; a dial back timing light with RPM display is one of the most valuable tools you can have. Try an Innova 3568; it's around $90...
 
Sounds like you have manifold vacuum to the advance at idle. It also sounds like you have stiff springs to limit the mechanical advance. To me this is bass ackwards.

Set your initial to about 12 with no vacuum and connect vacuum to the ported port. Mechanical typically all in by 2500. Assuming you have the proper initial advance for the cam you will have minimal throttle opening at idle to maintain RPM with no signal at the ported port. I don't know about EFI but in the real world ported is ported and manifold is manifold.

If you have ping on tip in then reduce the amount of vacuum advance. As a starting point the vac advance should add about 8 degrees of timing at full vacuum. You can also tee in a vac gauge to the ported port and see if the pinging is consistent with a strong vacuum signal and a long travel advance unit. If so then reduce the amount of advance at the vaccum can (limit travel with set screw) or by adding a stop to the arm. You want vacuum advance for a driver so make sure it's connected and providing a happy amount of advance.

Fuel mixture plays a roll but like you said it should be correct. However, don't count on it. The EFI units may favor a high intake vacuum to calibrate properly so you might want to read the AFR if you can. If it goes stupid lean then fatten it up in that area. Also 10.5:1 CR is not helping with 91 gas. Hot under hood temps also do not help but the computer should compensate. But a hot inlet charge will tend to ping even if the AFR is correct. What is the engine temp? Plug heat range? Might go colder on both.
 
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