Dissapointing performance

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Dusterguy said:
I think AJ was the dick now. "I dont reallly care if you agree with me" what talk is that..

I have talked some expert who have build Mopar engines 30 years here and he said: put all mechanical advance about 2200-2400rpm. That is advice what I have been listened. And that was what I did before and it worked. Now if someone says it need it to be 3400 rpm then I want to hear why.

I dont claim to be one that knows everything. Im here to learn and listen other people opinions.
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Did you even read his post he made that you quoted???

I quoted it below this so you can read it again.

AJ/FormS said:
All in by 2500 is for race cars that have big TCs, and two modes of operation; namely idle and WOT.And they don't run vacuum advance.
A streeter has to satisfy a bazzilion different operating parameters, not the least of which is a whole lotta time spent at under 3500 rpm. What is the point of sacrificing driveability below 3500 in the name of "I gotta race Distributor", or some such story. If you don't have a 3500Plus TC than you can't have all in before 3500, plain and simple. Well you can but it totally messes up part throttle, and economy.
See at part throttle and steady state, and lower rpms (sub 3500 say), the engine could be wanting 30 or 40 or occasionally 50 degrees of timing. But as soon as the throttle begins to tip in some of that has to drop out. And the faster you tip it in, or the heavier the loading, the quicker it has to drop out. So if your centrifugal timing is already walking a thin line to detonation, the trickier it will be to to satisfy the cruise and PT requirements.
Since you rarely ask for full power below 3500, and a 340/360 usually has more than enough cubes to spin-up street-tires even several degrees short of optimum timing,it seems to me somewhat foolish to completely throw away the tune in this most used area.
So as a compromise,recurve your dizzy to provide 34* at 3400, and idle timing of 12 to 14. Then install the biggest Vcan you can get (I have found none bigger than 22*). And start tuning that bad boy. The max timing can be controlled by shimming the arm. The rate of advance can be controlled by the little screw inside the hose-nipple.Then when you think you got it all dialed in pretty good; add 2* more initial, to get 36* at 3400, and start over.....And when you get that working, recurve it again to get 36* at 3200 or 3000 if you are feeling lucky....
As the engine starts to get the right PT timing it will be possible to start leaning out the low-speed circuits.
This is the road to fuel economy, cool running, and a torquey bottom end;free from detonation.
But while all this is going on, the engine running temperature has to be stable. If the temp is dancing around it will be impossible to work something out. Impossible. So if your carb is still sucking hot underhood air, don't even bother beginning a tune. You are just cooking the fuel, and cooking the air. And the inlet air temp will be all over the place. And the air-density will be dancing worse.
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Who recurve distibutor 15 times from 3400 to 2200? No one. If you know what is good amount of advance then you say it, if you dont better to not say anything.
What is best carb to use? Well just try every carb from 400 cfm to 800 cfm!
 
Dusterguy said:
That is one possibility and look like its the best thing to do.
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Fix your corked up exhaust first. If you don't and he doesn't recommend that first he isn't worth a grain of salt. Odds are if you don't fix it first he'll just laugh in your face and tell you to come back when your engine can breathe though.
 
To be honest I think the advance thing is most important and cheapest thing to fix. Then comes exhaust and carb.

edit: most important for low rpm performance
 
Dusterguy said:
Looks like your ego is so big that no one can disagree with you.

I made question for you, can you answer that or not.
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Mr. Dusterguy,
I am trying to save you time,aggravation, and money. I'm sorry you don't see it that way. I'm gonna cut you some slack on the ego statement,cuz,you can't hurt my feelings with that.
Here's the deal with timing. All internal combustion gas engines destined for common useage,will reach an rpm on the up-climb,under full-load WOT, where additional advance either helps nothing or hinders, in the production of torque. This point is almost always close to,or a little less than 3600 rpm, with unlimited octane fuel. Below this point, the timing has to be reduced under full-load WOT to prevent self destruction due to detonation.
Now the same engine, when heavily throttled, will accept a lot more timing, without complaint.
The trick is to pull timing at just the right speed and amount to reach that magical 3600 when transitioning from Part-Throttle to full-load WOT.
Your engine doesn't care where the timing is coming from, it only wants, not too much. So whether you give it 25* centrifugal plus 12* Vcan,or vice-versa it doesn't know. But to get 44* at 2400 for cruising, it cannot be done with a 9* can and 25* at 2400.And if you put a 22* can on there to get it, then the centrifugal will have to be limited to 22 at that rpm.
Further more, you can get a fair bit of primary throttle-opening before the Vcan starts to drop out. That means you can bring in a lot of Vcan on the primaries, and get back most of the "perceived" loss of centrifugal. And the higher your Dcr, the longer you can enjoy this effect.
Now if you have a Hi-stall, say 2400plus, this is less important, cuz your engine spends very little time down there, but on a stick-car, I spend a tremendous amount of time down there, and I used to drive 12,000 miles a year, so just 1mpg means a lot of money saved in gas not bought..
So to help you visualize this, try this; put a vacuum gauge in the cab where you can easily see it. Hook it up to a ported vacuum source , and drive around for a few hours, watching the gauge. Pretend that at all gauge readings over 14inches, the can would be giving you all it is able to.And that under 3 or 2 it is giving,very little. So drive around between 2 and 14, and imagine you were getting between 22 and 0 extra timing. Really, how often is the gauge reading zero? And how often is it over 10.
My guess is unless you are a kid, a huge amount of time will be spent with the gauge over 8 or 10. So why would you sacrifice something like 80% of the engines run-time with insufficient timing? Insufficient timing usually has to be band-aided with rich fuel settings.That means you are introducing extra fuel into the chambers to get a reasonable amount burned before the exhaust valve opens and dumps the still burning charge into the exhaust.It is still burning cuz the fire was lit too late and it has not had enough time to all burn. You can see this in action by dinking the idle timing back and forth.As the timing is increased the rpm goes up. See, you didn't give it more fuel to get the extra rpm,right. No you lit the fire earlier to burn all the extra fuel you were giving it to maintain the retarded timing!
And the stuff that didn't get burned;where did it go? That's right,the oil rings dragged it into the pan.
IDK, at one time,I thought this stuff was real important to me.At 12,000miles a year, I can save an easy $800Can in fuel and oil alone. What's that come to in 10 years? Answer; a free rebuild at the very least. Or maybe 2 years house rent?
 
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Dusterguy said:
To be honest I think the advance thing is most important and cheapest thing to fix. Then comes exhaust and carb.
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If the engine can't breathe the timing curve will be different then what it will be once the exhaust is fixed. Getting the timing curve "right" for your current exhaust is just a Band-Aid. Just get it close since it won't fix the real problem.

Fix the exhaust first, get the timing curve set and jetting right, put the correct convertor in it, get a bigger carb, jet it correctly and then recheck the timing curve again. Once that's done change the rear gear ratio. It will be a totally different car if you do this.

You'll be trying to find traction instead of whining about not being able to "burn out".
 
Most important thing to me is performance, then comes fuel economy and other things. That means I forget vacuum advance until I have dialed optimal idle and maximum timing + timing climbing rate. If these are done then I add vacuum advance to it if newer will.
 
T-N-T said:
If the engine can't breathe the timing curve will be different then what it will be once the exhaust is fixed. Getting the timing curve "right" for your current exhaust is just a Band-Aid. Just get it close since it won't fix the real problem.

Fix the exhaust first, get the timing curve set and jetting right, put the correct convertor in it, get a bigger carb, jet it correctly and then recheck the timing curve again. Once that's done change the rear gear ratio. It will be a totally different car if you do this.

You'll be trying to find traction instead of whining about not being able to "burn out".
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when the engine operate at 3000rpm and below then there isnt much hp coming out therefore any exhaust or carb is good enough.
 
Dusterguy said:
when the engine operate at 3000rpm and below then there isnt much hp coming out therefore any exhaust or carb is good enough.
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Then why do long tube headers with larger exhaust then what you have produce more torque in that rpm range???

With your cam you probably need about a 3000rpm converter though...
 
T-N-T said:
Then why do long tube headers with larger exhaust then what you have produce more torque in that rpm range???

With your cam you probably need about a 3000rpm converter though...
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Its the scavenging effect (nothing to do with exhaust pipe size) It is very different thing than restricting exhaust. I know I need bigger stall speed converter.
 
Dusterguy said:
Most important thing to me is performance, then comes fuel economy and other things. That means I forget vacuum advance until I have dialed optimal idle and maximum timing + timing climbing rate. If these are done then I add vacuum advance to it if newer will.
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How can performance be the most important thing to you with that exhaust system and headers you are using??? The same goes for your converter, gears and carb....

You are trying to tune a combination that is just costing you performance. Fix the combination first.
 
Dusterguy said:
Its the scavenging effect (nothing to do with exhaust size) It is very different thing than restricting exhaust. I know I need bigger stall speed converter.
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Restrictive exhaust lacks proper scavenging. How is that different?
 
Dusterguy said:
Who recurve distibutor 15 times from 3400 to 2200? No one. If you know what is good amount of advance then you say it, if you dont better to not say anything.
What is best carb to use? Well just try every carb from 400 cfm to 800 cfm!
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That's exactly what will happen if you don't fix the other issues first. You'll end up going through the timing and jetting after the other changes are made. once it can breathe you'll be starting all over.
 
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AJ/FormS said:
There must be something in the water you are drinking.....
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... thought it was kool-aid.

Probably 100 years combined experience in this thread, and everybody is saying the same thing.

Why ask questions when you don't want to hear the answers.
 
I don't get it, your asking for help but then telling people what you want to believe is the problem and argue your right? Over and OUT!
 
maybe the shifter linkage is messed up and it's starting out in second gear.

Everyone is giving solid advice. im sure over half have been in your same predicament. Me included.
Question on holley 4150

you could follow in my footsteps and max out a bunch of credit cards and have a slow racecar that is 99% street driven.

For the record AJs advice has gotten my 360 running way better. Thanks
 
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T-N-T said:
How can performance be the most important thing to you with that exhaust system and headers you are using??? The same goes for your converter, gears and carb....

You are trying to tune a combination that is just costing you performance. Fix the combination first.
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If performance is most important thing to me does it mean I have to have perfect car? I agree those parts that you and other peolple said arent ideal for my car and in future im going to change them.

Buying new springs to distributor doesnt cost anything and is easy to do. Im going to try it first.
 
"All internal combustion gas engines destined for common useage,will reach an rpm on the up-climb,under full-load WOT, where additional advance either helps nothing or hinders, in the production of torque. This point is almost always close to,or a little less than 3600 rpm, with unlimited octane fuel"
Are we talking about all out wot performance here or common usage settings from factory? If the first, then you statement is completely wrong. I have tried it and proved that 2000 rpm all in is much better than 3600 rpm all in. Same says expert guy who I talked. (with 30 years of experience).

There is optimum ignition advance for every rpm when engine operates at wot. If we forget detonation completely that statement still remains true. More rpm there is, more ignition advance there needs to be because fuel/air mixture has less time to ignite/burn (when starting at 1000 rpm and going up) then comes the magical point when engine doesnt need more advance. Why? Because there is so much swirling and turbulence in combustion chamber that it compensates the need of ignition advance. Now if you have experience of mopar engines you can say right away what that magical point is, I dont have, but I know it is not close a 3400.
 
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