Dissapointing performance

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Dusterguy said:
Do you say that "Your wife looks like crap." or do you say "Well I have seen some better ones but she is still pretty fine" Everyone can open page 1 and see who started to talk inappropriate.

Yes I asked for help, does it mean I cant suddenly disagree with anyone? I have my own opinion and often arguments to support my opinion. Im not afraid to disagree with anyone of you in this forum. I dont either scare to be wrong. I dont see trought internet who had build 100 mopar engines and who are not and I dont really care. Tell your own opinion with good arguments ant then we can discuss about things. If im not agree with someone that is not attack, it is normal conversation.
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If your wife came in wearing dog **** and you asked me how she looked. Then yup. I'd say she looks like crap. Honesty is the best policy.

You are more than entitled to your opinion. But let me ask you, again, how many people on here have said the exhaust needs to be changed? That the carb needs to be changed? You are asking us whats wrong. We are telling you whats wrong. Then you are telling us we are wrong. So why ask us? If you already know what it is, why bother asking? IF you are so sure what we tell you is wrong, and give you PROOF (for example, I posted a chart SHOWING that your exhaust can only support 289 horse) and you say you don't think that is a problem.

In fact you said:
Dusterguy said:
How much hp I will gain from 750 carb and 2.5 exhaust? maybe 20. It still miss 80hp..
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Where is your argument for 20 horse? I posted valid and mathematically proving info. Showing that a 2" exhaust is only capable for supporting 289 horse. That a 2.5" exhaust supports 463. And lets not forget that is the MAX that system supports. That assumes everything else runs well. I run a 3" exhaust on my 400+ horse 340 small block. Guess what I've never had a problem doing? Oh yeah, burnouts, whenever I want. With big fat 245's out back.

So once again:

The exhaust is killing AT LEAST 50HP. That's a VERY conservative number. VERY. Yes. Exhaust matters that much. Air goes in, must come out right? Why put on heads that can flow 500+ horsepower. But then an exhaust that can only flow 289 horsepower? Answer me that.

No, seriously. Tell me why you would put on head's that can flow 500+ horse. With an exhaust that can only flow 289 horse. I want to hear your "argument" or "opinion" for this.

crackedback said:
There is a lot of gold in that statement!

If it has headers on it, remove the exhaust at the collector and see how it responds. The exhaust is KILLING the engine and NOTHING you do with the distributor will fix that. As long as you continue on the current path, accept the rotten performance you've observed.

That engine with a good tune, decent carb and exhaust will make 420hp EASY!!!
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Don't bother. A dozen people have told him the exhaust and carb need to be changed. And he refuses to believe it.
 
Lustle said:
If your wife came in wearing dog **** and you asked me how she looked. Then yup. I'd say she looks like crap. Honesty is the best policy.

You are more than entitled to your opinion. But let me ask you, again, how many people on here have said the exhaust needs to be changed? That the carb needs to be changed? You are asking us whats wrong. We are telling you whats wrong. Then you are telling us we are wrong. So why ask us? If you already know what it is, why bother asking? IF you are so sure what we tell you is wrong, and give you PROOF (for example, I posted a chart SHOWING that your exhaust can only support 289 horse) and you say you don't think that is a problem.

In fact you said:


Where is your argument for 20 horse? I posted valid and mathematically proving info. Showing that a 2" exhaust is only capable for supporting 289 horse. That a 2.5" exhaust supports 463. And lets not forget that is the MAX that system supports. That assumes everything else runs well. I run a 3" exhaust on my 400+ horse 340 small block. Guess what I've never had a problem doing? Oh yeah, burnouts, whenever I want. With big fat 245's out back.

So once again:

The exhaust is killing AT LEAST 50HP. That's a VERY conservative number. VERY. Yes. Exhaust matters that much. Air goes in, must come out right? Why put on heads that can flow 500+ horsepower. But then an exhaust that can only flow 289 horsepower? Answer me that.

No, seriously. Tell me why you would put on head's that can flow 500+ horse. With an exhaust that can only flow 289 horse. I want to hear your "argument" or "opinion" for this.



Don't bother. A dozen people have told him the exhaust and carb need to be changed. And he refuses to believe it.
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yep! Some people are just so damn determined to learn the hard way. Think he needs to determine which way he wants to go with the car. Highway cruising or max performance/e.t. instead of:BangHead: This whole thing is really turning into a circle jerk!
 
crackedback said:
There is a lot of gold in that statement!

If it has headers on it, remove the exhaust at the collector and see how it responds. The exhaust is KILLING the engine and NOTHING you do with the distributor will fix that. As long as you continue on the current path, accept the rotten performance you've observed.

That engine with a good tune, decent carb and exhaust will make 420hp EASY!!!
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His headers are custom made 1 5/8" tube shorty's with 2" collectors. They would still kill the power output.
Out of the hole it's stall speed is so low it's not on the cam and when it gets on the cam it can't breathe worth a ****.

With a few changes to the driveline besides what you posted he can have a 420hp car that has traction issues. Then he'll have to tune the chassis to get it to hook so he can have a car that can haul ***.
 
crackedback said:
There is a lot of gold in that statement!

If it has headers on it, remove the exhaust at the collector and see how it responds. The exhaust is KILLING the engine and NOTHING you do with the distributor will fix that. As long as you continue on the current path, accept the rotten performance you've observed.


That engine with a good tune, decent carb and exhaust will make 420hp EASY!!!
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What you mean gold? Its normal to have black plugs when cruising around with low rpm with big camshaft. When cheking plugs after highspeed higway ride then they propably are looking more brown.

Tests have shown that timing comes in too quick and engine doest want it that way. Sure it helps low rpm performance if tuned right.
 
Lustle said:
If your wife came in wearing dog **** and you asked me how she looked. Then yup. I'd say she looks like crap. Honesty is the best policy.


You are more than entitled to your opinion. But let me ask you, again, how many people on here have said the exhaust needs to be changed? That the carb needs to be changed? You are asking us whats wrong. We are telling you whats wrong. Then you are telling us we are wrong. So why ask us? If you already know what it is, why bother asking? IF you are so sure what we tell you is wrong, and give you PROOF (for example, I posted a chart SHOWING that your exhaust can only support 289 horse) and you say you don't think that is a problem.

In fact you said:


Where is your argument for 20 horse? I posted valid and mathematically proving info. Showing that a 2" exhaust is only capable for supporting 289 horse. That a 2.5" exhaust supports 463. And lets not forget that is the MAX that system supports. That assumes everything else runs well. I run a 3" exhaust on my 400+ horse 340 small block. Guess what I've never had a problem doing? Oh yeah, burnouts, whenever I want. With big fat 245's out back.

So once again:

The exhaust is killing AT LEAST 50HP. That's a VERY conservative number. VERY. Yes. Exhaust matters that much. Air goes in, must come out right? Why put on heads that can flow 500+ horsepower. But then an exhaust that can only flow 289 horsepower? Answer me that.

No, seriously. Tell me why you would put on head's that can flow 500+ horse. With an exhaust that can only flow 289 horse. I want to hear your "argument" or "opinion" for this.



Don't bother. A dozen people have told him the exhaust and carb need to be changed. And he refuses to believe it.
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Its funny when I asked here fabo opinions about my previous combo (same combo exept heads) and one of the most reputable member said he likes my combo. Now its suddenly pile of crap even with better heads.

I have said many times that I will change these parts in future doesnt that say to you that I bellieve what you say. And yes exhaust is killing some horsepower I agree it like I said in very first post "they are small but not that small". Do I gain 50 hp from chancing to 2.5" exhaust? Will see it, but I doubt it to be honest. How ever I dont have any argument to support that opinion. I also have not said this engine is perfect. No there is no sense to put 2" exhaust to 500hp heads. But that is exhaust size that has always been in my car I haven changed it YET.
 
You are right. Something is wrong! Too little carb and too little exhaust for a performance setup. Even stock 340s had bigger carbs and 2.25 Exhaust.
 
Dusterguy said:
What you mean gold? Its normal to have black plugs when cruising around with low rpm with big camshaft.
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WRONG... but you know best. Only someone that has no idea how to tune an engine would make such a comment. Good luck, I won't waste any more time with you on this.
 
Alright......I want to help you so badly, I am gonna be a glutton for punishment and try ONE MORE TIME.

As stated multiple times, an engine is a self powered air pump. The more efficient it is, the more air it moves and the more power it makes. As you start making more power by adding high performance items such as big carburetors, intake manifolds, bigger cams and headers, you need to exponentially grow the exhaust system.

Here's why.

A high performance engine moves a LOT of air at a high velocity. That air exits at a very high velocity as exhaust. As the exhaust enters the headers, it picks up speed because it is still partially burning and because the headers 4 seperate tubes on each bank provide a reversion free (pretty much) path for the exhaust to exit the engine.

Reversion is the tendency of exhaust to want to flow back into the cylinder after combustion. What you have in your particular situation is a HUGE reversion issue. The reason is because your exhaust is 1) too small and 2) crushed on top of being too small. That engine is trying to pump probably three or four times the amount of exhaust into the exhaust system than it can scavenge, thus, you have a HUGE amount of back pressure, causing exhaust reversion. This reversion means burned exhaust is contaminating your cylinders on each and every combustion cycle and making power fall WAY off.

This leads to why this engine runs "so poorly" compared to "the other one". "The other one" was nowhere near the power level of your present engine, so, the exhaust.......even though in bad shape, could better handle the job the milder engine gave it. So, even though you have a "better" engine now, it is being choked to death by a small exhaust system that is crushed as well, plus, a smaller than needed carburetor.

Yes, I can see 100 HP loss here with all your problems combined. Even though your engine is "mismatched", it COULD make a TON more power just by fixing the exhaust, putting a bigger carburetor and finally sorting out the timing curve.

If you cannot understand that explanation and still continue to argue, then I honestly believe you are beyond help.
 
crackedback said:
WRONG... but you know best. Only someone that has no idea how to tune an engine would make such a comment. Good luck, I won't waste any more time with you on this.
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There is always carbon left from burning gas (expecially with radical camshaft where mixture atomization is poor at low engine speeds). If your engine/combustion chamber isnt hot enough it will stay there (carbon in plug). When you drive at higher load then plug temperature goes higher and it shows its "real" color and if your mixture is right and plug temp rate right then the color is coffee brown. When I checked plug I drove like 20 miles per hour for some time, it explains why plug was black.
 
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Dusterguy said:
There is always carbon left from burning gas. If your engine isnt hot enough it will stay there. When you drive at higher load then plug temperature goes higher and it shows its "real" color and if your mixture is right then the color is coffee brown. When I checked plug I drove like 20 miles per hour for some time, it explains why plug was black.
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Plugs should never be black. Period. Never. I drive around town all the time. My car is my daily driver any day it can be. In fact I just drove about 10km at speeds under 60kmh. Perfect conditions for the plugs to "look" rich. I guarantee I could go pull any plug right now, and it would be a light/golden brown. Plugs being black is bad. To much carbon. Probably from several problems we've all mentioned.
 
RustyRatRod said:
Alright......I want to help you so badly, I am gonna be a glutton for punishment and try ONE MORE TIME.

As stated multiple times, an engine is a self powered air pump. The more efficient it is, the more air it moves and the more power it makes. As you start making more power by adding high performance items such as big carburetors, intake manifolds, bigger cams and headers, you need to exponentially grow the exhaust system.

Here's why.

A high performance engine moves a LOT of air at a high velocity. That air exits at a very high velocity as exhaust. As the exhaust enters the headers, it picks up speed because it is still partially burning and because the headers 4 seperate tubes on each bank provide a reversion free (pretty much) path for the exhaust to exit the engine.

Reversion is the tendency of exhaust to want to flow back into the cylinder after combustion. What you have in your particular situation is a HUGE reversion issue. The reason is because your exhaust is 1) too small and 2) crushed on top of being too small. That engine is trying to pump probably three or four times the amount of exhaust into the exhaust system than it can scavenge, thus, you have a HUGE amount of back pressure, causing exhaust reversion. This reversion means burned exhaust is contaminating your cylinders on each and every combustion cycle and making power fall WAY off.

This leads to why this engine runs "so poorly" compared to "the other one". "The other one" was nowhere near the power level of your present engine, so, the exhaust.......even though in bad shape, could better handle the job the milder engine gave it. So, even though you have a "better" engine now, it is being choked to death by a small exhaust system that is crushed as well, plus, a smaller than needed carburetor.

Yes, I can see 100 HP loss here with all your problems combined. Even though your engine is "mismatched", it COULD make a TON more power just by fixing the exhaust, putting a bigger carburetor and finally sorting out the timing curve.

If you cannot understand that explanation and still continue to argue, then I honestly believe you are beyond help.
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I agree everything you said.
 
Lustle said:
Plugs should never be black. Period. Never. I drive around town all the time. My car is my daily driver any day it can be. In fact I just drove about 10km at speeds under 60kmh. Perfect conditions for the plugs to "look" rich. I guarantee I could go pull any plug right now, and it would be a light/golden brown. Plugs being black is bad. To much carbon. Probably from several problems we've all mentioned.
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I have seen black plugs even in stock cars with stock parts. It was BMW 6 cylinder engine.
 
Dusterguy said:
I have seen black plugs even in stock cars with stock parts. It was BMW 6 cylinder engine.
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Spark-Plug-Reading-1024x933.jpg


Tell me which one your plug looks like.
 
Dusterguy said:
There is always carbon left from burning gas. If your engine isnt hot enough it will stay there. When you drive at higher load then plug temperature goes higher and it shows its "real" color and if your mixture is right then the color is coffee brown. When I checked plug I drove like 20 miles per hour for some time, it explains why plug was black.
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You sir are hopelessly lost. Have you considered knitting?
 
I will not enter this trouble shooting discussion of poor performance. I will make a statement about the plugs. Black plugs indicate a problem.
 
318willrun said:
I will not enter this trouble shooting discussion of poor performance. I will make a statement about the plugs. Black plugs indicate a problem.
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Propably yes. It can be too fat mixture or too cold plug or car is driven at idle or other type of low load situation some time. Nothing to worry about if plug works.
 
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