ArdWrknTrk Posted September 29, 2019 Share Posted September 29, 2019 Chris - I doubt you can get enough vacuum drop in neutral to get the secondaries to come in, if that's what you are trying to do. With no load on the engine the vacuum won't go into the region needed to overcome the spring and open the secondaries. There's a test using a paper clip to test how far the secondaries open under load. Here's one discussion thereof: https://www.corvetteforum.com/forums/c1-and-c2-corvettes/760737-what-is-and-how-do-you-do-the-paper-clip-test-for-holley-s.html. And Jim is correct, mechanical secondaries aren't what you want in a truck. You'll create a big bog when you give it too much throttle and the RPM isn't up there yet. Plus, if you think you have bad MPG now, you ain't seen nothing yet. Been there, done that, and turned the back bumper blue while I watched the fuel gauge move opposite to the tach. Work up a deal with Jim for that 650 AVS. At least it'll determine if the carb is the problem. At best, you'll see a noticeable MPG improvement and you can bring the truck back for the show next year. Jim - I know you aren't about MPG, but it would be interesting to see what difference there is between the two carbs. Paul - Good luck in the autocross today. I really loved driving my Miata, so you'll have to report back on how much fun you have. Gary, It's a good idea. I have to drive by indicated mileage as it is. (gauges not really functional) *But new senders! And then I have lower profile tires than stock. (and I hate them) And then I have my randomly running out of fuel (although there seems to be 2-6 gallons still in there) So, if I can sort all that out I can get a baseline, and go for the bigger carb. Or, I have a 600cfm 4160 0-80457-s Chris could use that one too. Me? I'd put a tiny tywrap on the shaft and push hard up a hill to see if the secondaries are actually opening or not. Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 29, 2019 Author Share Posted September 29, 2019 Gary, It's a good idea. I have to drive by indicated mileage as it is. (gauges not really functional) *But new senders! And then I have lower profile tires than stock. (and I hate them) And then I have my randomly running out of fuel (although there seems to be 2-6 gallons still in there) So, if I can sort all that out I can get a baseline, and go for the bigger carb. Or, I have a 600cfm 4160 0-80457-s Chris could use that one too. Me? I'd put a tiny tywrap on the shaft and push hard up a hill to see if the secondaries are actually opening or not. Tywrap/paper clip - same test, just don't pull the tywrap very tight. Or, he could put the machine screw and nut in there and make them mechanical. He'll see what we mean. I have a 4180C on the shelf, but I have no idea if it is good. Took it off a non-running 351HO, so I doubt the jetting would be right for a 400. However, the stock Eddy 600 4106 I put on Big Blue as a test did great, so maybe it would. But it'd have to be rebuilt. Your AVS is the better choice. Anyway, hope you can get the baseline and then test the two carbs. Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Gary, It's a good idea. I have to drive by indicated mileage as it is. (gauges not really functional) *But new senders! And then I have lower profile tires than stock. (and I hate them) And then I have my randomly running out of fuel (although there seems to be 2-6 gallons still in there) So, if I can sort all that out I can get a baseline, and go for the bigger carb. Or, I have a 600cfm 4160 0-80457-s Chris could use that one too. Me? I'd put a tiny tywrap on the shaft and push hard up a hill to see if the secondaries are actually opening or not. Howdy Y'all, Sorry I haven't been on here for a while. But I fell at work and damaged my back. Been out of action for a while, still on the sick, lame and lazy list. I fell 6 feet or so off of a semi trailer. Any how, I did manage to find a cheap set of wheels from a 1500 Dodge and had the center hole milled out to fit my 86. Found some used tires to put on until I can afford some new ones. I hope these pictures work this time. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted September 29, 2019 Share Posted September 29, 2019 Tywrap/paper clip - same test, just don't pull the tywrap very tight. Or, he could put the machine screw and nut in there and make them mechanical. He'll see what we mean. I have a 4180C on the shelf, but I have no idea if it is good. Took it off a non-running 351HO, so I doubt the jetting would be right for a 400. However, the stock Eddy 600 4106 I put on Big Blue as a test did great, so maybe it would. But it'd have to be rebuilt. Your AVS is the better choice. Anyway, hope you can get the baseline and then test the two carbs. Gary I know it's the same. I was just falling in behind your recommendation. Now we need Bill's carburetor advise. Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 29, 2019 Author Share Posted September 29, 2019 Howdy Y'all, Sorry I haven't been on here for a while. But I fell at work and damaged my back. Been out of action for a while, still on the sick, lame and lazy list. I fell 6 feet or so off of a semi trailer. Any how, I did manage to find a cheap set of wheels from a 1500 Dodge and had the center hole milled out to fit my 86. Found some used tires to put on until I can afford some new ones. I hope these pictures work this time. Hamm0ckjames - So sorry to see about your injury! Hope you heal up quickly. Back injuries can be a lifetime problem. Jim - Yep. We do need Mr. Fuel System's recommendations. Â Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Howdy Y'all, Sorry I haven't been on here for a while. But I fell at work and damaged my back. Been out of action for a while, still on the sick, lame and lazy list. I fell 6 feet or so off of a semi trailer. Any how, I did manage to find a cheap set of wheels from a 1500 Dodge and had the center hole milled out to fit my 86. Found some used tires to put on until I can afford some new ones. I hope these pictures work this time. Â Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Link to comment Share on other sites More sharing options...
Hamm0ckjames Posted September 29, 2019 Share Posted September 29, 2019 Howdy Y'all, Sorry I haven't been on here for a while. But I fell at work and damaged my back. Been out of action for a while, still on the sick, lame and lazy list. I fell 6 feet or so off of a semi trailer. Any how, I did manage to find a cheap set of wheels from a 1500 Dodge and had the center hole milled out to fit my 86. Found some used tires to put on until I can afford some new ones. I hope these pictures work this time. Apparently posting pictures isn't my forte. But i picked up the old Dodge wheels for $100.00 and had the center holes milled out by a friend of mine for $60.00 and a pound of home made cow elk jerky. The used tires were a gimmie, mounted them yesterday, but i couldn't lift them onto the wheel balancer. No biggie, I'm not going to put any miles on her until I can get the four barrel intake project done. Which is on hold until i can get my back fixed. But now I've got some 16's on Moco like i wanted, hopefully I can get a 4 inch lift kit this year and the tires I want. But all things in good time i suppose. Just thought I would share my slow progress with ya'll. Link to comment Share on other sites More sharing options...
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