viven44 Posted June 18 Author Share Posted June 18 I think that's the same carb I had on Big Blue, and it worked well. The new carb + fuel pressure regulator has really woken up the truck. I don't seem to have rich exhaust anymore. I can still tell when the secondaries are opening as the truck really comes to life when they do, something I have never observed in Big Blue 2WD. I wonder if the secondaries are adjusted on the old Edelbrock 1411 to come on sooner. I do worry about the lack of a filter ahead of the regulator i.e. what if the Loctite PST 592 breaks down and gets into the carb. I did not apply it on the first 2-3 threads so it should be only towards the rear of the connectors but still I worry. The filter is located midstream. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 18 Share Posted June 18 The new carb + fuel pressure regulator has really woken up the truck. I don't seem to have rich exhaust anymore. I can still tell when the secondaries are opening as the truck really comes to life when they do, something I have never observed in Big Blue 2WD. I wonder if the secondaries are adjusted on the old Edelbrock 1411 to come on sooner. I do worry about the lack of a filter ahead of the regulator i.e. what if the Loctite PST 592 breaks down and gets into the carb. I did not apply it on the first 2-3 threads so it should be only towards the rear of the connectors but still I worry. The filter is located midstream. It's literally compounded for petroleum refineries and chemical plants. Link to comment Share on other sites More sharing options...
viven44 Posted June 18 Author Share Posted June 18 It's literally compounded for petroleum refineries and chemical plants. Good deal then Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 18 Share Posted June 18 It's literally compounded for petroleum refineries and chemical plants. Right. There's nothing to worry about on the sealant. It won't break down and I wouldn't have even let it set over night. It is good to go. But glad the new carb and the pressure regulator have sorted the problem. As for the secondaries, I assume all the 1411's get the same weight so there's no "adjusting". It isn't something that is easily done and only old hotrodders know how to do it - and no one wants to do it. While the AVS can be done easily, the AFB/Performer is a pain. Link to comment Share on other sites More sharing options...
viven44 Posted June 18 Author Share Posted June 18 Right. There's nothing to worry about on the sealant. It won't break down and I wouldn't have even let it set over night. It is good to go. But glad the new carb and the pressure regulator have sorted the problem. As for the secondaries, I assume all the 1411's get the same weight so there's no "adjusting". It isn't something that is easily done and only old hotrodders know how to do it - and no one wants to do it. While the AVS can be done easily, the AFB/Performer is a pain. Thanks!! I have my eyes on the Edelbrock 650AVS now. If I can have that "extra boost" a bit earlier that would be great. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 18 Share Posted June 18 Thanks!! I have my eyes on the Edelbrock 650AVS now. If I can have that "extra boost" a bit earlier that would be great. You can have it as early as you want. The conversation with Bill at Janey's therapy yesterday included about his SiL buying a double-pumper Holley. He kept telling him the Motorcraft 4100 that was on the engine was just right, and if he wanted a Holley to get one with vacuum secondaries. But no, he had to have a double-pumper. Sure enough the thing fell on its face when the secondaries opened. Put the 4100 back on and he had lots more power and no bog. But you may be able to tune the AVS to get the boost a bit earlier than with the "AFB". The latter is adjusted so no engine will bog, so that usually leaves something on the table. But adjusting an AFB is no fun and is not easily reversed, so when you go too far you then have to take it back apart and put weight back on. How much? Enough so you don't have to take it apart again. Link to comment Share on other sites More sharing options...
viven44 Posted June 18 Author Share Posted June 18 You can have it as early as you want. The conversation with Bill at Janey's therapy yesterday included about his SiL buying a double-pumper Holley. He kept telling him the Motorcraft 4100 that was on the engine was just right, and if he wanted a Holley to get one with vacuum secondaries. But no, he had to have a double-pumper. Sure enough the thing fell on its face when the secondaries opened. Put the 4100 back on and he had lots more power and no bog. But you may be able to tune the AVS to get the boost a bit earlier than with the "AFB". The latter is adjusted so no engine will bog, so that usually leaves something on the table. But adjusting an AFB is no fun and is not easily reversed, so when you go too far you then have to take it back apart and put weight back on. How much? Enough so you don't have to take it apart again. That makes total sense. I have experienced the 'over-carbed' effect when I had my 84 Bronco with a 302. I had a Edelbrock 1405 (600CFM) on it. It definitely fell on its face when the secondaries opened and I couldn't tell when the secondaries came on, all I knew was the truck wouldn't go and pretty much the second half of the throttle was a waste and my only option was to kick-down to a lower gear to make it go I was on the look for a 1403 (500CFM) but never got to it but advised the new owner to strongly consider that. I am curious though, how is the accelerator pump "shot" calibrated with the timing of the secondaries opening i.e. if there is an excess "shot" and not sufficient air that creates a temporary rich condition.. My understanding is that when the secondaries open, a bigger venturi is created and the source of that fuel draw is still the bowl (?) The accelerator pump provides an immediate dose for instant gratification but I'd really like that "shot" to be timed with extra air at the same time i.e. make the secondaries come on sooner (Which we know is not possible on the manual secondaries without too much effort) or have the pump work a bit later. Those 3 holes in the pump lever control the "shot" amount, but not the timing if I understand correctly. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 18 Share Posted June 18 Thanks!! I have my eyes on the Edelbrock 650AVS now. If I can have that "extra boost" a bit earlier that would be great. I'm planning on Thursday afternoon (with a 'real feel' of 112°F 🥵) Don't worry. We'll figure it out. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 18 Share Posted June 18 That makes total sense. I have experienced the 'over-carbed' effect when I had my 84 Bronco with a 302. I had a Edelbrock 1405 (600CFM) on it. It definitely fell on its face when the secondaries opened and I couldn't tell when the secondaries came on, all I knew was the truck wouldn't go and pretty much the second half of the throttle was a waste and my only option was to kick-down to a lower gear to make it go I was on the look for a 1403 (500CFM) but never got to it but advised the new owner to strongly consider that. I am curious though, how is the accelerator pump "shot" calibrated with the timing of the secondaries opening i.e. if there is an excess "shot" and not sufficient air that creates a temporary rich condition.. My understanding is that when the secondaries open, a bigger venturi is created and the source of that fuel draw is still the bowl (?) The accelerator pump provides an immediate dose for instant gratification but I'd really like that "shot" to be timed with extra air at the same time i.e. make the secondaries come on sooner (Which we know is not possible on the manual secondaries without too much effort) or have the pump work a bit later. Those 3 holes in the pump lever control the "shot" amount, but not the timing if I understand correctly. The pump shot isn't part of the equation - unless your secondaries open immediately when you floor it and that's a very rare happening. Like you were cruising at 4000 RPM and then nailed it. Usually you nail it and the engine revs up over a few seconds and gets to an RPM where the secondaries finally open. But the pump shot is long gone as it only covers the brief period between when you nail it and the fraction of a second later when the fuel being pulled in via vacuum can respond. (Air is a lot less dense and, therefore, reacts much more quickly than fuel.) Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 18 Share Posted June 18 The pump shot isn't part of the equation - unless your secondaries open immediately when you floor it and that's a very rare happening. Like you were cruising at 4000 RPM and then nailed it. Usually you nail it and the engine revs up over a few seconds and gets to an RPM where the secondaries finally open. But the pump shot is long gone as it only covers the brief period between when you nail it and the fraction of a second later when the fuel being pulled in via vacuum can respond. (Air is a lot less dense and, therefore, reacts much more quickly than fuel.) Absolutely true. I can cite examples of orbital trajectories that are affected by low level, but not high level (say above 60k') air disturbances. Link to comment Share on other sites More sharing options...
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