OMFG... No Performance... MAJOR ISSUES
08-21-2008, 11:57 PM
#21
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Same here...I'd run that thing locked, no advance. I'd set it at 34-36 degrees and call it a day.
fuel pressure as said above also...if that needle sticks open, it's gonna be a bad day..
fuel pressure as said above also...if that needle sticks open, it's gonna be a bad day..
09-07-2008, 11:52 PM
#23
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hmmmm... it does sound like a vacuum problem. I had a huge problem when i was running a 2 inch spacer under the carb. i had a problem getting the gaskets, top and bottom of the spacer, to seal. i am sure i will come up with more problem i have had. wish i could help more bro
09-10-2008, 12:49 PM
#24
few good reads on vacuum advance:
http://www.highperformancepontiac.co...ech/index.html
http://www.tr6web.com/Documents/tr6/vacuumadvance.html
http://www.chevyhiperformance.com/ho...438/index.html
69 chevy 350 with pistons 0.030" over
-Edelbrock 600cfm carb
-Torquer 2 intake manifold
-Comp 230 236 490 490 @ 110 flat tappet
-Dart iron eagle platinum heads 200cc
-black spark plugs
the torker is a single plane intake rated at 2500-6500 rpm and the dart heads are huge. with those 2 parts on a 350 the only somewhat correct choice was a smaller 600 cfm carb to help offset the poor vacuum signal at low rpms to gain some idle quality. but my guess is with those 200 cc heads and a 230/236 @110 lsa cam you have no vacuum at rpms less than 2000 so there's no way the carb can meter fuel and give a stable idle.
unplug the vacuum advance and make sure all the ports are sealed and you have no vacuum leak. Put a vacuum gauge on the intake manifold and set and get a stable timing setting of somewhere between 10-20 deg BTDC then tune your idle mixture and observe the vacuum gauge. google manifold vacuum gauge for troubleshooting tips to find out how to read it. my best guess is you have the parts for a high rpm circle track motor that shouldn't see below 3000 rpm, any attempt at idling would be futile.
the black as hell spark plugs can be caused by too cold spark plug. If your running cold spark plugs I would step up probably 2 heat ranges hotter for tuning, and run the car easy. Cold plugs will only make it that much harder to tune at idle. Run the engine easy and pull a couple plugs and read the color, they should be light tan with no black soot on them (dry fouled).
For your application you'd be way better off with a pair of vortec heads and a properly sized dual-plain intake. The cam isn't too bad at 230/236 @ 110 if your headers are 1-3/4" but a cam step downward to something like the 224/232 @ 112 neighborhood might provide better low rpm performance and idle quality.
http://www.highperformancepontiac.co...ech/index.html
http://www.tr6web.com/Documents/tr6/vacuumadvance.html
http://www.chevyhiperformance.com/ho...438/index.html
69 chevy 350 with pistons 0.030" over
-Edelbrock 600cfm carb
-Torquer 2 intake manifold
-Comp 230 236 490 490 @ 110 flat tappet
-Dart iron eagle platinum heads 200cc
-black spark plugs
the torker is a single plane intake rated at 2500-6500 rpm and the dart heads are huge. with those 2 parts on a 350 the only somewhat correct choice was a smaller 600 cfm carb to help offset the poor vacuum signal at low rpms to gain some idle quality. but my guess is with those 200 cc heads and a 230/236 @110 lsa cam you have no vacuum at rpms less than 2000 so there's no way the carb can meter fuel and give a stable idle.
unplug the vacuum advance and make sure all the ports are sealed and you have no vacuum leak. Put a vacuum gauge on the intake manifold and set and get a stable timing setting of somewhere between 10-20 deg BTDC then tune your idle mixture and observe the vacuum gauge. google manifold vacuum gauge for troubleshooting tips to find out how to read it. my best guess is you have the parts for a high rpm circle track motor that shouldn't see below 3000 rpm, any attempt at idling would be futile.
the black as hell spark plugs can be caused by too cold spark plug. If your running cold spark plugs I would step up probably 2 heat ranges hotter for tuning, and run the car easy. Cold plugs will only make it that much harder to tune at idle. Run the engine easy and pull a couple plugs and read the color, they should be light tan with no black soot on them (dry fouled).
For your application you'd be way better off with a pair of vortec heads and a properly sized dual-plain intake. The cam isn't too bad at 230/236 @ 110 if your headers are 1-3/4" but a cam step downward to something like the 224/232 @ 112 neighborhood might provide better low rpm performance and idle quality.
09-10-2008, 11:35 PM
#25
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Your vacuum advance should be hooked up to full manifold vacuum!
taken from another post....
"Now, to the widely-misunderstood manifold-vs.-ported vacuum aberration. After 30-40 years of controlling vacuum advance with full manifold vacuum, along came emissions requirements, years before catalytic converter technology had been developed, and all manner of crude band-aid systems were developed to try and reduce hydrocarbons and oxides of nitrogen in the exhaust stream. One of these band-aids was "ported spark", which moved the vacuum pickup orifice in the carburetor venturi from below the throttle plate (where it was exposed to full manifold vacuum at idle) to above the throttle plate, where it saw no manifold vacuum at all at idle. This meant the vacuum advance was inoperative at idle (retarding spark timing from its optimum value), and these applications also had VERY low initial static timing (usually 4 degrees or less, and some actually were set at 2 degrees AFTER TDC). This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it."
taken from another post....
"Now, to the widely-misunderstood manifold-vs.-ported vacuum aberration. After 30-40 years of controlling vacuum advance with full manifold vacuum, along came emissions requirements, years before catalytic converter technology had been developed, and all manner of crude band-aid systems were developed to try and reduce hydrocarbons and oxides of nitrogen in the exhaust stream. One of these band-aids was "ported spark", which moved the vacuum pickup orifice in the carburetor venturi from below the throttle plate (where it was exposed to full manifold vacuum at idle) to above the throttle plate, where it saw no manifold vacuum at all at idle. This meant the vacuum advance was inoperative at idle (retarding spark timing from its optimum value), and these applications also had VERY low initial static timing (usually 4 degrees or less, and some actually were set at 2 degrees AFTER TDC). This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it."
09-11-2008, 01:39 AM
#26
are you sure you lined up the distributor with number 1 piston??? sometimes people forget or dont get it close enough or might have it 180 out which means it didnt get compression when you turned the motor over..... im a newby take it easy on me if im way off
09-12-2008, 02:22 AM
#27
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Your vacuum advance should be hooked up to full manifold vacuum!
taken from another post....
"Now, to the widely-misunderstood manifold-vs.-ported vacuum aberration. After 30-40 years of controlling vacuum advance with full manifold vacuum, along came emissions requirements, years before catalytic converter technology had been developed, and all manner of crude band-aid systems were developed to try and reduce hydrocarbons and oxides of nitrogen in the exhaust stream. One of these band-aids was "ported spark", which moved the vacuum pickup orifice in the carburetor venturi from below the throttle plate (where it was exposed to full manifold vacuum at idle) to above the throttle plate, where it saw no manifold vacuum at all at idle. This meant the vacuum advance was inoperative at idle (retarding spark timing from its optimum value), and these applications also had VERY low initial static timing (usually 4 degrees or less, and some actually were set at 2 degrees AFTER TDC). This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it."
taken from another post....
"Now, to the widely-misunderstood manifold-vs.-ported vacuum aberration. After 30-40 years of controlling vacuum advance with full manifold vacuum, along came emissions requirements, years before catalytic converter technology had been developed, and all manner of crude band-aid systems were developed to try and reduce hydrocarbons and oxides of nitrogen in the exhaust stream. One of these band-aids was "ported spark", which moved the vacuum pickup orifice in the carburetor venturi from below the throttle plate (where it was exposed to full manifold vacuum at idle) to above the throttle plate, where it saw no manifold vacuum at all at idle. This meant the vacuum advance was inoperative at idle (retarding spark timing from its optimum value), and these applications also had VERY low initial static timing (usually 4 degrees or less, and some actually were set at 2 degrees AFTER TDC). This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it."
