Bullnose Gator Posted July 30 Author Share Posted July 30 Got it, thanks. I've also seen others say they only had to adjust or replace the stock carb and not touch their timing. Should I address the carb first and then see if the timing is an issue, or do they both need to be done in tandem in my case? Speaking of vrest...thanks for explaining what it does. Now, can you confirm where it is? Based on the diagram, I think it's the top port on the yellow vcv valve pictured below, but not sure. I did more tinkering/learning last night, and tried to run vac lines to the dist adv from one of the manifold ports through the vcv/vrest. The yellow lines on the diagram are what I was trying to do, the blue lines in the pic are what I did. Let me know if the two line up... It idled better, but still bad. The vacuum gauge (hooked to the carb manifold port this time) read around 42 inches. I turned the vac adv clockwise until it was closed, then went 2 turns counterclockwise at a time, it didn't idle good anywhere along the way. Link to comment Share on other sites More sharing options...
viven44 Posted July 30 Share Posted July 30 Speaking of vrest...thanks for explaining what it does. Now, can you confirm where it is? Based on the diagram, I think it's the top port on the yellow vcv valve pictured below, but not sure. I did more tinkering/learning last night, and tried to run vac lines to the dist adv from one of the manifold ports through the vcv/vrest. The yellow lines on the diagram are what I was trying to do, the blue lines in the pic are what I did. Let me know if the two line up... It idled better, but still bad. The vacuum gauge (hooked to the carb manifold port this time) read around 42 inches. I turned the vac adv clockwise until it was closed, then went 2 turns counterclockwise at a time, it didn't idle good anywhere along the way. This video should answer a lot of questions about VREST.... Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 30 Share Posted July 30 Speaking of vrest...thanks for explaining what it does. Now, can you confirm where it is? Based on the diagram, I think it's the top port on the yellow vcv valve pictured below, but not sure. I did more tinkering/learning last night, and tried to run vac lines to the dist adv from one of the manifold ports through the vcv/vrest. The yellow lines on the diagram are what I was trying to do, the blue lines in the pic are what I did. Let me know if the two line up... It idled better, but still bad. The vacuum gauge (hooked to the carb manifold port this time) read around 42 inches. I turned the vac adv clockwise until it was closed, then went 2 turns counterclockwise at a time, it didn't idle good anywhere along the way. Right, the diagram shows the little blue plastic orifice in the line farthest from the threaded end of the VCV. 42" of vacuum is something beyond outer space. Vivek works in semi so I'd differ to him but I don't think it's possible to get beyond 30", and in a truck 22" would be really quite high. You use the distributor wrench to adjust static timing and springs, weights and slots to determine how soon and how much mechanical advance you get as engine rpm increase and vacuum goes away. The vacuum advance is used to adjust how much advance the engine has with the throttle closed. I'd probably be looking for 12° BTDC static, 26-32° with vacuum and 38ish all in, around 3,200 rpm. But my engine is not yours, nor are we going to drive the same, with the same load. You really need to go read the instructions Gary's got posted and follow them step by step (that's important!) Link to comment Share on other sites More sharing options...
viven44 Posted July 30 Share Posted July 30 42" of vacuum is something beyond outer space. Vivek works in semi so I'd differ to him but I don't think it's possible to get beyond 30", and in a truck 22" would be really quite high. Yes... even getting close to absolute vacuum (nearly 30") needs like 2 cryo pumps... We probably need a picture of your gauge so we can see what you are looking at.. Well nevermind.... I think he is quoting cm Hg. So 42cm Hg = 16.5 " Hg Link to comment Share on other sites More sharing options...
Bullnose Gator Posted July 30 Author Share Posted July 30 Speaking of vrest...thanks for explaining what it does. Now, can you confirm where it is? Based on the diagram, I think it's the top port on the yellow vcv valve pictured below, but not sure. I did more tinkering/learning last night, and tried to run vac lines to the dist adv from one of the manifold ports through the vcv/vrest. The yellow lines on the diagram are what I was trying to do, the blue lines in the pic are what I did. Let me know if the two line up... It idled better, but still bad. The vacuum gauge (hooked to the carb manifold port this time) read around 42 inches. I turned the vac adv clockwise until it was closed, then went 2 turns counterclockwise at a time, it didn't idle good anywhere along the way. Thanks, V. I probably (definitely) did something wrong. I'll hook the gauge back up and post a pic. Jim, are you saying I should move the vac lines to the last two darker blue ports, as shown below? Also, I thought Gary was referring me to the last part of those instructions for how to adjust the dist vac adv with the allen wrench, the 2 turns at a time part. Are you saying Scottie's distributor rebuild kit is required, not just recommended? I might go pick up whatever Holly/Edelbrock carb one of the local auto parts stores keep in stock that is closest to one of the ones you recommended tonight. The 4180c obviously wasn't designed for this kind of tuning, or for use without the emissions components and related 2000 feet of vacuum lines. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 30 Share Posted July 30 Thanks, V. I probably (definitely) did something wrong. I'll hook the gauge back up and post a pic. Jim, are you saying I should move the vac lines to the last two darker blue ports, as shown below? Also, I thought Gary was referring me to the last part of those instructions for how to adjust the dist vac adv with the allen wrench, the 2 turns at a time part. Are you saying Scottie's distributor rebuild kit is required, not just recommended? I might go pick up whatever Holly/Edelbrock carb one of the local auto parts stores keep in stock that is closest to one of the ones you recommended tonight. The 4180c obviously wasn't designed for this kind of tuning, or for use without the emissions components and related 2000 feet of vacuum lines. No, you're on the right VCV, but you need the distributor coming from the center, the restricted orifice in the outermost port and straight manifold vacuum (code red) to the other port. The diagram is a graphic representation. I can't draw it any better than the factory. Read the instructions. You need to start at the beginning and complete each step before moving to the next. (I think they are quite clear about this!) Scottie doesn't sell any kit. He sells complete recurved distributors. He has two pages that show how to make those adjustments, but can't explain what adjustments you need to make because every engine/vehicle/use case is different. To make those adjustments you need to understand slot width, use the springs to achieve starting and full advance at the proper rpm for your application, and set the vacuum up so that it's limited just shy of detonation (using whatever fuel and load you intend to deal with) Like Gary, I'm stuck using premium because I don't want to give up performance/acceleration by setting my static lower than 12, and I guess this cam doesn't like lugging. Link to comment Share on other sites More sharing options...
Bullnose Gator Posted July 31 Author Share Posted July 31 Speaking of vrest...thanks for explaining what it does. Now, can you confirm where it is? Based on the diagram, I think it's the top port on the yellow vcv valve pictured below, but not sure. I did more tinkering/learning last night, and tried to run vac lines to the dist adv from one of the manifold ports through the vcv/vrest. The yellow lines on the diagram are what I was trying to do, the blue lines in the pic are what I did. Let me know if the two line up... It idled better, but still bad. The vacuum gauge (hooked to the carb manifold port this time) read around 42 inches. I turned the vac adv clockwise until it was closed, then went 2 turns counterclockwise at a time, it didn't idle good anywhere along the way. Alright. So a few dummy things I did (I was raised by women, if you haven't assumed by now, bear with me): 1) I thought the VREST was built into the VCV, but then finally had time when I got off to watch the video V shared and understood. I added that back to the line and the original elbow for the dist line. Let me know if I'm still ignorant. 2) Of course, I was reading the wrong side of the gauge. (#FisherPriceMyFirstVacuumGauge) It was actually in the 16-18 inch range, but flickering pretty hard. And that was to start. It got worse (lower) the hotter it got and when I tried to adjust the front idle mixture screws. 3) I'm probably not using the right size vacuum hoses as I try to Frankenstein this together to see what works and what doesn't. Current set up below. I'll have to dig into the timing tomorrow, Jim, but the instructions Gary linked imply replacing springs etc in the distributor, but you say Scottie doesn't sell them. Where do I buy those if I try to do it myself? Link to comment Share on other sites More sharing options...
viven44 Posted July 31 Share Posted July 31 Alright. So a few dummy things I did (I was raised by women, if you haven't assumed by now, bear with me): 1) I thought the VREST was built into the VCV, but then finally had time when I got off to watch the video V shared and understood. I added that back to the line and the original elbow for the dist line. Let me know if I'm still ignorant. 2) Of course, I was reading the wrong side of the gauge. (#FisherPriceMyFirstVacuumGauge) It was actually in the 16-18 inch range, but flickering pretty hard. And that was to start. It got worse (lower) the hotter it got and when I tried to adjust the front idle mixture screws. 3) I'm probably not using the right size vacuum hoses as I try to Frankenstein this together to see what works and what doesn't. Current set up below. I'll have to dig into the timing tomorrow, Jim, but the instructions Gary linked imply replacing springs etc in the distributor, but you say Scottie doesn't sell them. Where do I buy those if I try to do it myself? You have a rather low vacuum reading if you are running a stock cam... probably need to troubleshoot that... About the VREST and distributor connections -- the center port of that yellow vacuum control valve needs to be hooked up to the distributor vacuum advance... -- the top port of that control valve connects to intake manifold vacuum port through the VREST -- the bottom port of that control valve connects to intake manifold vacuum straight On my Bronco with the 460... since my vacuum is really stable and good, I don't even use VREST. The distributor is hooked up straight to the intake manifold full-time. About your low vacuum reading... it could be because --- one or two of your cylinders may not be firing --- Your intake to EGR plate / EGR plate to carb gaskets are possibly leaky if you are not using the original style gaskets. You can use the gaskets below which are Felpro's equivalent of the OEM motorcraft ones. I used the ones below on the Bronco and they worked really well. Jim might suggest new old stock OEMs instead. EGR to Carb Gasket - https://www.amazon.com/gp/product/B000C2AD6C/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Intake to EGR gasket ⦁ https://www.amazon.com/Fel-Pro-60003-Carburetor-Mounting-Gasket/dp/B000C2E4TO Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 31 Share Posted July 31 Alright. So a few dummy things I did (I was raised by women, if you haven't assumed by now, bear with me): 1) I thought the VREST was built into the VCV, but then finally had time when I got off to watch the video V shared and understood. I added that back to the line and the original elbow for the dist line. Let me know if I'm still ignorant. 2) Of course, I was reading the wrong side of the gauge. (#FisherPriceMyFirstVacuumGauge) It was actually in the 16-18 inch range, but flickering pretty hard. And that was to start. It got worse (lower) the hotter it got and when I tried to adjust the front idle mixture screws. 3) I'm probably not using the right size vacuum hoses as I try to Frankenstein this together to see what works and what doesn't. Current set up below. I'll have to dig into the timing tomorrow, Jim, but the instructions Gary linked imply replacing springs etc in the distributor, but you say Scottie doesn't sell them. Where do I buy those if I try to do it myself? Were all here to help one another. I don't care if you were raised by girl scouts or wolves, but it's a real challenge to diagnose anything over the internet. We all have to be on the same page. 1) So now you understand why I was saying "the little blue plastic orifice", and didn't mean the blue VCV? By "elbow" do you mean the rubber 90° at the vacuum advance can??? This keeps the routing neat but shouldn't effect function. 2) 16-18, flickering and worse as it gets hot is not good. A gasket leak won't cause jumping, just a low reading Bad intake valves, loose timing chain or an outrageously hot cam with a ton of overlap will. You need to mess with the mixture screws to try and find the highest and most steady vacuum. 3) Hose size really shouldn't matter. Vacuum works on potential, a larger hose should simply add volume to the system, not change anything. Are we looking at the Crane Cams pdf of their adjustable vacuum advance for Ford & Mercury? You understand that you need to be sure the valves and timing chain are in perfect shape before ANY ignition or carburetor adjustments Like I said above the springs come in a set sold by MrGasket (928G) that doesn't seem to be in stock anywhere until the middle of September.. You can get a pair of light springs and use one, but I have one medium and one light in my dizzy.to get some advance in quickly.and all in by 3k Be sure to buy the ones marked Ford/Mercury You may need to weld up the slot or bush the stop ear with a brass tube or piece of plastic fuel line to limit mechanical advance.(Scott says how many thousandths of an inch per degree) Here are some other instructions: https://vb.foureyedpride.com/showthread.php?22229-The-Ultimate-Duraspark-Distributor-Timing-Guide . Link to comment Share on other sites More sharing options...
viven44 Posted July 31 Share Posted July 31 Were all here to help one another. I don't care if you were raised by girl scouts or wolves, but it's a real challenge to diagnose anything over the internet. We all have to be on the same page. 1) So now you understand why I was saying "the little blue plastic orifice", and didn't mean the blue VCV? By "elbow" do you mean the rubber 90° at the vacuum advance can??? This keeps the routing neat but shouldn't effect function. 2) 16-18, flickering and worse as it gets hot is not good. A gasket leak won't cause jumping, just a low reading Bad intake valves, loose timing chain or an outrageously hot cam with a ton of overlap will. You need to mess with the mixture screws to try and find the highest and most steady vacuum. 3) Hose size really shouldn't matter. Vacuum works on potential, a larger hose should simply add volume to the system, not change anything. Are we looking at the Crane Cams pdf of their adjustable vacuum advance for Ford & Mercury? You understand that you need to be sure the valves and timing chain are in perfect shape before ANY ignition or carburetor adjustments Like I said above the springs come in a set sold by MrGasket (928G) that doesn't seem to be in stock anywhere until the middle of September.. You can get a pair of light springs and use one, but I have one medium and one light in my dizzy.to get some advance in quickly.and all in by 3k Be sure to buy the ones marked Ford/Mercury You may need to weld up the slot or bush the stop ear with a brass tube or piece of plastic fuel line to limit mechanical advance.(Scott says how many thousandths of an inch per degree) Here are some other instructions: https://vb.foureyedpride.com/showthread.php?22229-The-Ultimate-Duraspark-Distributor-Timing-Guide . Based on his pics the bottom port of the 3 port VCV seems to be open... might explain why things get worse when hot as there would be no vacuum advance after things get hot. Jeremy, if that is the case, please connect that bottom port of the VCV straight to the intake manifold ... Link to comment Share on other sites More sharing options...
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