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Discussion Starter #1
I have a relatively stock 350 in my 65 wagon. It was running a 2 barrel with a stock intake. I put on a Performer intake and Holley Avenger 670 and I cant seem to get it running good under heavy acceleration(no load). It had 65 jets in but when I pulled the plugs they were white. So I went to a 70 and then 72. It will accelerate decent but only when pressed rather slowly. Am I looking in the wrong direction or did I just not get it yet. ANY help would be greatly appreciated.
Thanks
 

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Discussion Starter #3
It's in park. I haven't even pulled it out of the garage. Is there really that much of a difference?
 

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I also thought the revs would give enough vac. But I did just take it for a spin. It ran better than I thought, although it still hesitates rather harshly and when I got back revving it hard gave some black smoke and then white as I got backed off of it. This time I tried a softer spring on the secondaries (yellow) and put the 70 jets back in. Im guessing the smoke is important but Im not sure how I get both black and white like that?:confused:
 

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How are you revving it? Are you going full throttle or just light presses? You have to go past the setting of the power valve before the secondaries open.

Black smoke means your carb is set too rich. White I thought was coolant. You sure it wasn't gray? Did it have a blue-ish tint? Could be burning oil...or maybe tire smoke... :D

Matt
 

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David_D. said:
I would think the increased RPM would create more vacuum thus opening up the secondaries. :confused:
The secondaries don't open because there isn't any load on the engine requiring more air.

Here's how it works:
Torque is a measure of Force. Force x distance = work. HP is a measure of work or load.... derived from torque times distance (in this case RPM) divided by a constant 5252.

To make HP you need energy which is produced by combining Fuel and Air through combustion. About 10-15 lbs of air are needed for every lb of fuel.
A 300 HP engine requires at least 3,000 lbs of air per hour @ full throttle and load.
When the engine is free wheeling it makes very little HP since it isn't doing much work. I think you might be surprised that when you are revving your engine it's producing probably less than 25 hp or what ever is required to overcome friction and drive the belts and water pump. Because of that it only needs to ingest a very small amount of air. Revving the engine doesn't accomplish anything other than make noise.
 

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Discussion Starter #9 (Edited)
ok, so if I have this right...idle is only adjusted by the mixture screws, revving while sitting in park and cruising is adjusted by the jets, and accelerating WHILE driving is done with the accelerator pump then the power valve and hard accelerating while driving is the secondaries? And even though the rabbit is faster the turtle gets there first. This gets more interesting as it gets more complicated.
 

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I thought we had a basic How to Tune thread in Best of Tech (we do) but it missing the "how to tune" part! I guess we'll need to work on that unless someone already has it in another thread.
 

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Discussion Starter #12
I just wanted to thank all of you for your help. From what you guys said and that great link to bob2000 the car is 100 times better, still not finished but some small adjustments I wouldn't have even looked at made a world of difference. I'm one of those people stuck in the middle, between a complete novice and TRUE mechanic. Most sites the questions seem rather simple and so are the answers, but here the questions are not so simple but the answers are still explained in a way you can understand. So for all of us that don't know it all, but want to...Thanks
 
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