viven44 Posted August 24 Author Share Posted August 24 There are also different step up rods (metering rods) with different diameters. Chrysler used a two stage piston that required a taller cover and longer jets so the rods wouldn't come out of the jets. The piston had a small spring that in conjunction with the nain spring would give an early "tip in" at a slightly richer mixture. Holley did the same, but had a 2 stage power valve to do it. The older Carter carbs, the WCFB, WCD, WGD had a mechanical limiter on the metering rod system that prevented them from going too lean at higher throttle openings. The ThermoQuad OEM models had a similar system and like the older carbs had the metering rods linked together with a single piston. Thank you Bill, I am leaving everything else at stock at the moment as I am unable to tell whether I need to go rich or lean. I am going to need an A/F meter sooner than later. As little as I know about carburetors, it is fascinating how more can be got out with small changes. I know there is more on the table! Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 24 Share Posted August 24 There are also different step up rods (metering rods) with different diameters. Chrysler used a two stage piston that required a taller cover and longer jets so the rods wouldn't come out of the jets. The piston had a small spring that in conjunction with the nain spring would give an early "tip in" at a slightly richer mixture. Holley did the same, but had a 2 stage power valve to do it. The older Carter carbs, the WCFB, WCD, WGD had a mechanical limiter on the metering rod system that prevented them from going too lean at higher throttle openings. The ThermoQuad OEM models had a similar system and like the older carbs had the metering rods linked together with a single piston. Welcome to the world of easy tuning on a Carterbrock! You changed the springs w/o pulling the cover, and you can change the rods the same way. Just loosen the screws holding the covers and rotate them out of the way and out come the rods and springs. No lost fuel, no gaskets to leak, and no o-ring to get pinched. Plus, no accelerator pump nor power valve to split. Had a guy tell me on Facebook recently that he had a backfire through the carb which bent the metering rods on an Edelbrock. My dad taught me not to argue with fools so I left it at that. Â Link to comment Share on other sites More sharing options...
85lebaront2 Posted August 24 Share Posted August 24 Thank you Bill, I am leaving everything else at stock at the moment as I am unable to tell whether I need to go rich or lean. I am going to need an A/F meter sooner than later. As little as I know about carburetors, it is fascinating how more can be got out with small changes. I know there is more on the table! You need to do some spark plug reading, they will tell you a lot regarding mixture. The cylinders are grouped 1467 on one side of the carburetor (unless you are using either an open chamber manifold or an Offenhauser 360 manifold) and 2358 on the other side. if you pull and inspect 1 & 2 or 5 & 6 you are seeing both sides of the carburetor. If you want to fully understand what effect various parts of a carburetor do what to the mixture, I sent Gary a file a while back, it is a Weber publication called "Technical Introduction to the Master Catalog" it explains what each part of the fuel metering and delivery circuit do: https://www.garysgaragemahal.com/weber-technical-introduction.html Link to comment Share on other sites More sharing options...
viven44 Posted August 24 Author Share Posted August 24 You need to do some spark plug reading, they will tell you a lot regarding mixture. The cylinders are grouped 1467 on one side of the carburetor (unless you are using either an open chamber manifold or an Offenhauser 360 manifold) and 2358 on the other side. if you pull and inspect 1 & 2 or 5 & 6 you are seeing both sides of the carburetor. If you want to fully understand what effect various parts of a carburetor do what to the mixture, I sent Gary a file a while back, it is a Weber publication called "Technical Introduction to the Master Catalog" it explains what each part of the fuel metering and delivery circuit do: https://www.garysgaragemahal.com/weber-technical-introduction.html Thanks Bill, I will print that and that will be a great read on my upcoming work trip. I am driving the Bronco a lot more than I anticipated. It has been my daily driver, I actually don't have another vehicle at the moment with AC... I am strongly considering getting an AFR meter to have more long-term real-time feedback... I have a couple of questions --- I am running a single exhaust ... Can I install a single A/F meter past and muffler and close to the tail pipe and get away with it? --- which A/F meter is recommended ? I came across the options below... not sure if these are good or if y'all recommend another one. Clamp with bung https://www.amazon.com/GlowShift-Clamp-Wideband-Oxygen-Adapter/dp/B07KY1TJ6B/ref=pd_bxgy_d_sccl_2/144-9369957-7318344?pd_rd_w=dPpmp&content-id=amzn1.sym.04064661-569a-4d64-8aef-6cc4eefc1253&pf_rd_p=04064661-569a-4d64-8aef-6cc4eefc1253&pf_rd_r=E8ZF18J2R3DKKHY0QDZS&pd_rd_wg=KNDwW&pd_rd_r=be4d72ff-32c9-473b-8143-f42b5fdd4384&pd_rd_i=B07KY1TJ6B&psc=1 AF meter kit https://www.amazon.com/GlowShift-Tinted-Digital-Wideband-Ratio/dp/B007GE8I7K/ref=asc_df_B007GE8I7K/?tag=hyprod-20&linkCode=df0&hvadid=693375481814&hvpos=&hvnetw=g&hvrand=5559705226627597832&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9026945&hvtargid=pla-889969374891&psc=1&mcid=82f6a8dec45e3219a6be44ae5eeb7e82&gad_source=1 Link to comment Share on other sites More sharing options...
85lebaront2 Posted August 24 Share Posted August 24 Thanks Bill, I will print that and that will be a great read on my upcoming work trip. I am driving the Bronco a lot more than I anticipated. It has been my daily driver, I actually don't have another vehicle at the moment with AC... I am strongly considering getting an AFR meter to have more long-term real-time feedback... I have a couple of questions --- I am running a single exhaust ... Can I install a single A/F meter past and muffler and close to the tail pipe and get away with it? --- which A/F meter is recommended ? I came across the options below... not sure if these are good or if y'all recommend another one. Clamp with bung https://www.amazon.com/GlowShift-Clamp-Wideband-Oxygen-Adapter/dp/B07KY1TJ6B/ref=pd_bxgy_d_sccl_2/144-9369957-7318344?pd_rd_w=dPpmp&content-id=amzn1.sym.04064661-569a-4d64-8aef-6cc4eefc1253&pf_rd_p=04064661-569a-4d64-8aef-6cc4eefc1253&pf_rd_r=E8ZF18J2R3DKKHY0QDZS&pd_rd_wg=KNDwW&pd_rd_r=be4d72ff-32c9-473b-8143-f42b5fdd4384&pd_rd_i=B07KY1TJ6B&psc=1 AF meter kit https://www.amazon.com/GlowShift-Tinted-Digital-Wideband-Ratio/dp/B007GE8I7K/ref=asc_df_B007GE8I7K/?tag=hyprod-20&linkCode=df0&hvadid=693375481814&hvpos=&hvnetw=g&hvrand=5559705226627597832&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9026945&hvtargid=pla-889969374891&psc=1&mcid=82f6a8dec45e3219a6be44ae5eeb7e82&gad_source=1 Do youself a big favor, stay away from Chinazon for automotive parts. First if you want a good AFR system, mine is from Innovate and is an excellent and very accurate unit. It will also integrate into my BE tuning software. https://www.innovatemotorsports.com/shop-all/measurement/wideband-air-fuel-ratio.html Link to comment Share on other sites More sharing options...
viven44 Posted August 25 Author Share Posted August 25 Do youself a big favor, stay away from Chinazon for automotive parts. First if you want a good AFR system, mine is from Innovate and is an excellent and very accurate unit. It will also integrate into my BE tuning software. https://www.innovatemotorsports.com/shop-all/measurement/wideband-air-fuel-ratio.html Excellent! Let me look into that. Link to comment Share on other sites More sharing options...
viven44 Posted August 25 Author Share Posted August 25 Excellent! Let me look into that. I was reading the manual... sounds like I will need to pick an exhaust pipe either on the left or right bank close to the manifold. I guess AFR reading on one side should hopefully be indicative of health on the other side. https://www.innovatemotorsports.com/wp/content/uploads/2022/05/MTX-OL_Manual_110163.pdf Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 25 Share Posted August 25 I was reading the manual... sounds like I will need to pick an exhaust pipe either on the left or right bank close to the manifold. I guess AFR reading on one side should hopefully be indicative of health on the other side. https://www.innovatemotorsports.com/wp/content/uploads/2022/05/MTX-OL_Manual_110163.pdf If you install an AFR meter do NOT put it on the accessory feed. And preferably put it on something that is only powered when the engine is running. I, too, have an Innovate AFR MTX-L+ and I just put the third O2 sensor on it - @ $100 each. After the 2nd one went out I called Innovate and the guy said the problem is that I have the power going to it in accessory. So I turn the key to accessory and the O2 sensor heats up, and then I turn the key to Start and a wave of relatively cold air comes down the pipe and cracks the ceramic in the sensor. So I've put it on a relay pulled in by the stator output of the alternator. That works fairly well as it only pulls in when the engine is running. But, sometimes when I let off the throttle and the RPM's drop they drop far enough that the relay drops out and the AFR gauge goes back into heating mode. That doesn't hurt anything and is far better than killing another sensor, but I need to move it to the fuel pump power feed. Link to comment Share on other sites More sharing options...
85lebaront2 Posted August 25 Share Posted August 25 I was reading the manual... sounds like I will need to pick an exhaust pipe either on the left or right bank close to the manifold. I guess AFR reading on one side should hopefully be indicative of health on the other side. https://www.innovatemotorsports.com/wp/content/uploads/2022/05/MTX-OL_Manual_110163.pdf If you have a wye into a single pipe you can use it there. My 1990 front pipes on Darth have a short cross pipe just in front of where the catalytic converter would go. That is where the factory O2 sensor was installed. Link to comment Share on other sites More sharing options...
viven44 Posted August 25 Author Share Posted August 25 If you install an AFR meter do NOT put it on the accessory feed. And preferably put it on something that is only powered when the engine is running. I, too, have an Innovate AFR MTX-L+ and I just put the third O2 sensor on it - @ $100 each. After the 2nd one went out I called Innovate and the guy said the problem is that I have the power going to it in accessory. So I turn the key to accessory and the O2 sensor heats up, and then I turn the key to Start and a wave of relatively cold air comes down the pipe and cracks the ceramic in the sensor. So I've put it on a relay pulled in by the stator output of the alternator. That works fairly well as it only pulls in when the engine is running. But, sometimes when I let off the throttle and the RPM's drop they drop far enough that the relay drops out and the AFR gauge goes back into heating mode. That doesn't hurt anything and is far better than killing another sensor, but I need to move it to the fuel pump power feed. Thanks Gary! Thats very useful. And btw, where is your sensor installed ? In my experience, the 460 exhaust is like a blow torch so it should be hot enough to be installed even at the tailpipe... I just don't want to kill the sensor by mounting it too close to the manifold Link to comment Share on other sites More sharing options...
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