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  • #31
    Originally posted by dave.g.in.gansevoort View Post

    And remember the one experiment where we needed 140 ish psi and series ganged pumps to get there, then regulated by using a bypass like you said. Crude but effective if you need higher pressure. If I remember correctly we used Walbro Nissan replacement pumps. That was almost 30 years ago...
    relying on a fuel pressure regulator is a work around but not a solution. Regulators fail, and in this case, it could cause some pretty severe damage due to the pressures in play. Add to that if you overfill your tank, there could be enough pressure at the tank to cause full pressure to go into your carb...

    Doing it all wrong since 1966

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    • #32
      Originally posted by SuperBuickGuy View Post

      relying on a fuel pressure regulator is a work around but not a solution. Regulators fail, and in this case, it could cause some pretty severe damage due to the pressures in play. Add to that if you overfill your tank, there could be enough pressure at the tank to cause full pressure to go into your carb...
      Absolutely correct! We did this in a HDD dyno cell, pumping from/to a 55 gallon fuel barrel, in an overpack. Full automatic fire protection, etc,etc,etc.

      Now for the rest of the story as Paul Harvey used to say. We were working with a catalyst manufacturer developing a lean NOx catalyst system. This is very different from the crap selective catalytic reduction converters that came along. The system needs a little extra dose of fuel to light off, which can be done 2 ways: introduce a small amount into the exhaust stream , or with modern electronically controlled engines, by making a randome cylinder run rich, you know just like modern electronically controlled engines in passenger car systems that dither lean to rich around stoic.

      We didn't have that so I bought an aftermarket fuel injection driver, and put an injector in the exhaust before the cat. Over a period of cycles I adjusted the fuel curves to get just enough fuel in the exhaust to make it work. Now there is a down side, about a 2-3% fuel economy hit, but considering that these cats are developed for gasoline engines and work for 200,000 plus miles with no maintenance, I think that it could have been a better choice for trucks than SCR, with the maintenance issues and need for DEF and a complete separate system.

      That's my 2 dollars worth, but what did I know? The upper management had pretty much already gotten in bed with all the various players as they saw SCR as a quicker way to reduce NOx. I think history will show that lean NOx catalysts would have been the correct choice.

      Oh man, I did it again! Off on another windmill tilt...

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      • #33
        I accept I am a complete idiot on this stuff, but warm the car up to 180. Drive, electric fans do not go on, it drops to 150 degrees. Its 50 degrees out, but city streets not over 30, its just dumping fuel like crazy and cooling the block, right? I can see cooling on the highway without fans, but not crawling on the street. Ends up going to 165 tops. So done with this thing. Looking for a LS Cam to maybe find some proper numbers other than this big duration thumper, but nobody responds to custom cam requests.

        What do we do, move AFR to 16 to see if it will lean out enough or is something else seriously wrong. This cam has a 107 LSA, so most newer injection cams are 112-115. Does that make enough of a difference? Will advancing it 6 degrees maybe help since I cant find a cam we like with low duration numbers on the shelf?

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        • #34
          by no means am I an expert - it is my understanding the wide lobe separation is to clean up the idle so it doesn't hunt so much.

          Can you watch the AFR while you drive? On my Holley HP system, you can hook a laptop up and see in realtime where it is running and what the numbers are. If you AFR numbers seem erratic you MAY have a bad O2 sensor. I know that Holley was pushing the NTK units which are about 3 times more than the Bosch ones.

          Are your fans turned on my the ECU or by a stand alone sensor?

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          • #35
            Originally posted by anotheridiot View Post
            I accept I am a complete idiot on this stuff, but warm the car up to 180. Drive, electric fans do not go on, it drops to 150 degrees. Its 50 degrees out, but city streets not over 30, its just dumping fuel like crazy and cooling the block, right? I can see cooling on the highway without fans, but not crawling on the street. Ends up going to 165 tops. So done with this thing. Looking for a LS Cam to maybe find some proper numbers other than this big duration thumper, but nobody responds to custom cam requests.

            What do we do, move AFR to 16 to see if it will lean out enough or is something else seriously wrong. This cam has a 107 LSA, so most newer injection cams are 112-115. Does that make enough of a difference? Will advancing it 6 degrees maybe help since I cant find a cam we like with low duration numbers on the shelf?
            change your fuel table to be full stoichiometric at 160 degrees. The Holley system has cold, warm, warmer and fully warmed levels that allow for fine-tuning of the air/fuel ratio. I'd avoid leaning it out too much because it could detonate and you probably wouldn't hear it. When you adjust the a/f ratios, be sure and also adjust the enrichment tables as well... I fought my car for longer then I care to admit wondering why my a/f ratio wasn't going to where I set it... yeah, it was a Billy Mays moment "but wait, there's more!"
            Doing it all wrong since 1966

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            • #36
              Originally posted by cstmwgn View Post
              by no means am I an expert - it is my understanding the wide lobe separation is to clean up the idle so it doesn't hunt so much.

              Can you watch the AFR while you drive? On my Holley HP system, you can hook a laptop up and see in realtime where it is running and what the numbers are. If you AFR numbers seem erratic you MAY have a bad O2 sensor. I know that Holley was pushing the NTK units which are about 3 times more than the Bosch ones.

              Are your fans turned on my the ECU or by a stand alone sensor?
              ECU handles the fans and they are definitely not going on. Yeah, I saw those 270.00 O2 sensors. As long as the regular ones last, I cant see getting that much life out of it. AFR hunts some, but is between 12.7 and 13.5. I actually drove home while my son watched the laptop yesterday.

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              • #37
                Originally posted by SuperBuickGuy View Post

                change your fuel table to be full stoichiometric at 160 degrees. The Holley system has cold, warm, warmer and fully warmed levels that allow for fine-tuning of the air/fuel ratio. I'd avoid leaning it out too much because it could detonate and you probably wouldn't hear it. When you adjust the a/f ratios, be sure and also adjust the enrichment tables as well... I fought my car for longer then I care to admit wondering why my a/f ratio wasn't going to where I set it... yeah, it was a Billy Mays moment "but wait, there's more!"
                I go back to messing with a vacuum secondary carb, playing with the springs and getting that lean pop. I would kill for a lean pop on this thing and then back away. I doubt it would ever happen. I wish there was a way to turn off two injectors because that is how fat this seems to be. I know it only gets harder from here and wish we could be learning a damned thing.

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                • #38
                  I am sorry to ask such stupid questions but it seems you have conflicting information. The AFRs you listed seem reasonable. Maybe not Prius caliber but clearly very driveable. Could something be causing the O2 sensor to get a lean reading - air leak, too close to the end of the exhaust (open collector) or not in direct flow path of the collector or ????

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                  • #39
                    there are no stupid questions, but it is exactly the aggravation. We used to have the bung in the exhaust pipe past the collectors. Its the magnaflow kit for the camaro, so there were two elbows that close in to get to the H pipe. We plugged that one and welded in new bungs in the collector thinking we would get a more accurate reading. They are hooker long tube headers. There is no mileage to speak of so its pretty clear that it is rich. We try to let it learn on its own, and it runs like crap and shows that it stopped learning. We keep spare 02 sensors and change them out and get the same reading.

                    I would think there was some other problem, but it cools like our 98 Malibu used to, I never once heard that fan go on. We clearly checked that the enrichment for cooling is only in the danger zone of 190.

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                    • #40
                      Originally posted by anotheridiot View Post
                      there are no stupid questions, but it is exactly the aggravation. We used to have the bung in the exhaust pipe past the collectors. Its the magnaflow kit for the camaro, so there were two elbows that close in to get to the H pipe. We plugged that one and welded in new bungs in the collector thinking we would get a more accurate reading. They are hooker long tube headers. There is no mileage to speak of so its pretty clear that it is rich. We try to let it learn on its own, and it runs like crap and shows that it stopped learning. We keep spare 02 sensors and change them out and get the same reading.

                      I would think there was some other problem, but it cools like our 98 Malibu used to, I never once heard that fan go on. We clearly checked that the enrichment for cooling is only in the danger zone of 190.
                      18"-22" from the exhaust port - move the sensor too far downstream and it won't be warm enough to get a good reading... but with that said, the O2 really isn't helping you because when it's cold, it's running off tables (not closed loop)
                      Last edited by SuperBuickGuy; March 18, 2022, 09:04 PM.
                      Doing it all wrong since 1966

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                      • #41
                        Originally posted by SuperBuickGuy View Post

                        18"-22" from the exhaust port - move the sensor too far downstream and it won't be warm enough to get a good reading... but with that said, the O2 really isn't helping you because when it's cold, it's running off tables (not closed loop)
                        at least you explaining this helps make sense why the AFR looks good when it is running this rich.

                        So, is it a 1976 chevy pickup truck that we need to put a piece of cardboard in front of the kick ass aluminum radiator to get heat in the motor?

                        Is it even possible that fuel can cool an engine this much?

                        We did check the thermostat, replaced it with a new 180. Just got a 195 to see if it would stay closed long enough where it gets to 195 then cools to 175 ish. I would just rather have a fun car to drive and use the battery to cool anti freeze with the kickass fan and shroud instead of an extra gallon of gas per 7 mile trip. Did all the thinkable things, like unscrew the sensors, (the sniper temp sensor is at the front of the block, the gauge is towards the rear) to see if there was an air pocket.

                        We have tried to start over, let it learn on its own, but it always gets to the same rich result. How do you find out if an injector is just stuck open?

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                        • #42
                          I don't know anything about the sniper. I have a Terminator X that on my stock 5.0 mustang.

                          Does the sniper have the wizard start up tunes? Did you create one? (On the Terminator you can pick one one of three different cam choice ranges). Which cam choice did you choose small medium or large? I have seen mustang guys mess this up the duration number in Holley are .050. they are thinking the .006 or something. Also on the Terminator if you select the big one it does alpha-n or some crap during idle.

                          According to some talking head on YouTube only choose one or two never three.

                          I think I have seen the sniper used on a bunch of the Drag week cars. Maybe try to ask in one of the FB groups?

                          I can't imagine the exhaust is cooling that quickly, if it is what about rapping the headers.

                          Disclaimer: this advice comes with a money back guarantee, You get what you paid for it
                          Last edited by Russell; March 20, 2022, 05:36 AM.
                          http://www.bangshift.com/forum/forum...-consolidation

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                          • #43
                            Originally posted by anotheridiot View Post

                            at least you explaining this helps make sense why the AFR looks good when it is running this rich.

                            So, is it a 1976 chevy pickup truck that we need to put a piece of cardboard in front of the kick ass aluminum radiator to get heat in the motor?

                            Is it even possible that fuel can cool an engine this much?

                            We did check the thermostat, replaced it with a new 180. Just got a 195 to see if it would stay closed long enough where it gets to 195 then cools to 175 ish. I would just rather have a fun car to drive and use the battery to cool anti freeze with the kickass fan and shroud instead of an extra gallon of gas per 7 mile trip. Did all the thinkable things, like unscrew the sensors, (the sniper temp sensor is at the front of the block, the gauge is towards the rear) to see if there was an air pocket.

                            We have tried to start over, let it learn on its own, but it always gets to the same rich result. How do you find out if an injector is just stuck open?
                            sure - that said, I'd worry about hot spots.

                            you'll see it dribbling when the motor is 'off' and only in one venturi
                            Last edited by SuperBuickGuy; March 20, 2022, 08:06 AM.
                            Doing it all wrong since 1966

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                            • #44
                              Finally talked to a cam guy at Brian Tooley Racing, said the thumper cam we have is going to be making the MAP sensor read erratically making it think that it is always under power so it wants to keep adding fuel.

                              I asked my son if there was a way to cheat the MAP sensor until we can get a different cam, like the terrorists in Die Hard 2 when they changed 0 elevation and drive planes into the ground. (Yeah, I am really ready for the high tech hot rodding). He thinks the entire scale could be moved, but looking at a day of 60 then back into the 40's and 50's so we probably wont be learning anything. The TKX should be here by then and give us time to spend while we are waiting for weather.

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                              • #45
                                I'd be interested in hearing the why... it's not like the air is reverting through the plenum.... not saying he's wrong, but I'd also have the MAP sensor displaying to verify what he's saying makes sense.... thumpr cams mess with the exhaust to give you that lumpy sound - so it DOES affect the O2 sensor, especially if it's too far downstream from the exhaust
                                Doing it all wrong since 1966

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