[rohrt]

Sounds like you forgot to pull the vacuum advance line back off when checking the idle timing.

You really need to get a tach too. I had stalling issues with one car and found I just had the idle set to low. My loud exhaust was throwing me off.

Pull the vacuum line to the can again and plug it.
Take a reading of the idle advance timing for us.
Take another readin with the vacuum can connected. Then we can see how much advance your can is set at.

If you did have it connected when you took the idle reading then we know your connected to manifold souce.

I wouldn't be all that concerned with factory specs. My tempest won't hardly run with the factory spec of 6 deg BTDC initial. I have set for 14-18 and it runs 200% better. Different gas today, carb and unknown part all bets are off IMO.

I saw in one of your post on the first page that you said you took the air cleaner off and the idle was much better? And I see you just mentioned moving it a bit and changing the idle.

Is the flapper stuck closed in the snorkle? Possible vacuum leak in the line to the diaphram on the snorkle? Maybe try flipping the lid upside down and running it old school as a test I'm not expert but I think it should point to the driver side like you shown in post 13. From factory there was a metal line that ran from the valve cover to the air cleaner in place of that breather cap that is there now.

I can't for the life of me think why moving the cleaner would change the idle unless the air clean is touching something on the car it shouldn't be.

[PontGuy]

Originally Posted by rohrt

I wouldn't be all that concerned with factory specs. My tempest won't hardly run with the factory spec of 6 deg BTDC initial. I have set for 14-18 and it runs 200% better. Different gas today, carb and unknown part all bets are off IMO.

And you can add the fact that different distributors came with different curves depending on application (and they have often been swapped out too.) That's why I like to start out backwards and set the all-in first. 34-36 deg is almost always close to right for a performance 400. Then see where that puts the base timing. Once you know where the base timing is then you shouldn't have to check the all-in again unless you mess around with the distributor internals.

Just make sure that you get it right- agree with all the comments about remembering to remove the vacuum hose, make double-sure you are connected to #1 cylinder (front right) etc. And be safe! I shut down, make adjustments, and re-check. Yes tightening can throw it off. Just have to fiddle with it.

Oh and yes, agree that moving the air cleaner should not affect the idle. Another thing that could cause this is if the bottom base plate is tightening down on the carb linkage somewhere. This is a common with Q-jets and some aftermarket air cleaners where the base can hit the top of the accelerator pump lever. So you need to figure this out too.

I am 6'3 so I didn't fit in the Viper well at all. And I don't think it could be very comfortable for anyone. The seat is set a weird angle too, to make room for the trans tunnel. But if I could have gotten my friend's Viper for only 30K it would be sitting in my garage now.

[Darth Menace]

Originally Posted by PontGuy

And you can add the fact that different distributors came with different curves depending on application (and they have often been swapped out too.) That's why I like to start out backwards and set the all-in first. 34-36 deg is almost always close to right for a performance 400. Then see where that puts the base timing. Once you know where the base timing is then you shouldn't have to check the all-in again unless you mess around with the distributor internals.

Just make sure that you get it right- agree with all the comments about remembering to remove the vacuum hose, make double-sure you are connected to #1 cylinder (front right) etc. And be safe! I shut down, make adjustments, and re-check. Yes tightening can throw it off. Just have to fiddle with it.

Oh and yes, agree that moving the air cleaner should not affect the idle. Another thing that could cause this is if the bottom base plate is tightening down on the carb linkage somewhere. This is a common with Q-jets and some aftermarket air cleaners where the base can hit the top of the accelerator pump lever. So you need to figure this out too.

I am 6'3 so I didn't fit in the Viper well at all. And I don't think it could be very comfortable for anyone. The seat is set a weird angle too, to make room for the trans tunnel. But if I could have gotten my friend's Viper for only 30K it would be sitting in my garage now.

There are guys as tall/taller than with Vipers. Just get a 2 inch seat lowering kit, and adjust the seat/pedals accordingly. The Viper is built like me...for speed, not comfort .

Anyway, I will get around to the car later today with a video if that helps. I haven't been taking it as easy as I am suppose to after my surgery, so waking up in pain today sucked. I am not sure crouching underneath the dash to fix the cluster helped any either. I have to do car stuff in small chunks if I want to heal at all.

[Darth Menace]

I am going to get a tach later today. Wanting to get this beast taken care of now that we know it's likely not in it's last legs.

Yes, the vacuum advance is set up to the manifold...there is a spot for it on my edelbrock carb, but it is plugged. No idea what the difference is, so it is on the manifold.

About the air cleaner. I just assumed my moving it should cause RPM difference, sucking in more or less air. Anyway, what I didn't mention is that the snorkle is not on super tight, so that moving was while it was still on the car...just swiveling it really. This is probably something that is my own stupidity.

Originally Posted by rohrt

You really need to get a tach too. I had stalling issues with one car and found I just had the idle set to low. My loud exhaust was throwing me off.

Pull the vacuum line to the can again and plug it.
Take a reading of the idle advance timing for us.
Take another readin with the vacuum can connected. Then we can see how much advance your can is set at.

If you did have it connected when you took the idle reading then we know your connected to manifold souce.

I wouldn't be all that concerned with factory specs. My tempest won't hardly run with the factory spec of 6 deg BTDC initial. I have set for 14-18 and it runs 200% better. Different gas today, carb and unknown part all bets are off IMO.

I saw in one of your post on the first page that you said you took the air cleaner off and the idle was much better? And I see you just mentioned moving it a bit and changing the idle.

Is the flapper stuck closed in the snorkle? Possible vacuum leak in the line to the diaphram on the snorkle? Maybe try flipping the lid upside down and running it old school as a test I'm not expert but I think it should point to the driver side like you shown in post 13. From factory there was a metal line that ran from the valve cover to the air cleaner in place of that breather cap that is there now.

I can't for the life of me think why moving the cleaner would change the idle unless the air clean is touching something on the car it shouldn't be.

[nytrainer]

once you set the initial timing the mechanical advance (centrifical) of the distributor should increase the timing in the neighborhood of roughly 20 degrees. You are saying that your initial is 30 degrees and total equals 36 and that would lead me to believe your mechanical advance in the distributor is only providing six degrees advance. A little early in the game to say there is something wrong with the base plate in your distributor so best to have you rerun the tests and get some numbers. I definitely would not have my initial at 30 degrees.

[Darth Menace]

Originally Posted by nytrainer

once you set the initial timing the mechanical advance (centrifical) of the distributor should increase the timing in the neighborhood of roughly 20 degrees. You are saying that your initial is 30 degrees and total equals 36 and that would lead me to believe your mechanical advance in the distributor is only providing six degrees advance. A little early in the game to say there is something wrong with the base plate in your distributor so best to have you rerun the tests and get some numbers. I definitely would not have my initial at 30 degrees.

Alright, I will get this done. I will take a video which should help better explain.


That being said, I didnt have the vacuum advance plugged in any way. I just unplugged the hose at the vacuum advance and kept it sitting there. Also, it was not in Neutral or drive while I did any of thise. I don't know if either of these should have made a difference.

[nytrainer]

You are using manifold vacuum for the distributor advance then when you unplug it from the distributor you must plug the hose with something, I use a golf tee because it's tapered, otherwise the RPM's will raise and you're not setting your true initial timing. You are introducing some centrifical advance when its not at idle. so look at the instructions again and try to follow it setting your initial then you could check your all in. We can go from there.