bgd73 Posted January 1, 2007 Share Posted January 1, 2007 I have an 87 GL with hitachi. I ridded the problems I had with it and now it is down to fuel, it is just out of reach of the more air flow down the barrells to stay happy with enough fuel. I got real lucky on a fuel pump several years ago that seems to be non-existent. I do not want to go that route again. I have 2 fuel pumps, one being a spfi high pressure, and the other a 4-7 psi, slightly high. Rather than another fuel pump, I want a regulator that does it all and allows me to tune it in maximum for the unique non-oem flow I have created. This does work as I have done it before, the carb whistled like a tea pot and really took in some flow (again, due to the lucky find of strange fuel pump, I can't seem to find anymore) I found several regulators that go below the 4 pound mark, one brand name being holley (part 12-804). Anybody has done this, advice on a good regulator (<$50) would be great. And weber convert advice not needed. The hitachi does my old soob well. A dynamical regulator would be awesome, I am uncertain of brands and makes, types etc. A custom soob expert would be great. As of now, the holley seems to fit, but I can't seem to find a how to or definitions of how dynamical it really is. Link to comment Share on other sites More sharing options...
Quidam Posted January 1, 2007 Share Posted January 1, 2007 Ok bgd, tell me what I'm missing here. As long as the float bowl doesn't run out of fuel, that's all it needs in the way of a fuel pump. Or am I missing something? Yes, regulattors are available as well as pumps with various psi ratings. I had a warmed over small block Chevy that would empty the Holley float bowls at the top of third gear. This, with a high flow mechanical pump on the motor. I installed an AC electric pump in a box in the bed of the '57 Chevy pickup. On/off switch on the dash for when I beat on it took care of that issue. On second thought, what am I missing here? Link to comment Share on other sites More sharing options...
Hodaka Rider Posted January 1, 2007 Share Posted January 1, 2007 I have an 87 GL with hitachi. I ridded the problems I had with it and now it is down to fuel, it is just out of reach of the more air flow down the barrells to stay happy with enough fuel. Unless you truly are running the float bowl clean (not likely on a basically stock EA-82) the most you would need to do is re-jet it. Again, being a basically stock EA-82, it's not likely you need to re-jet. If you truly are hearing a whistling from your carb, you might have a problem there. Link to comment Share on other sites More sharing options...
bgd73 Posted January 1, 2007 Author Share Posted January 1, 2007 ok. figured it out. There is the holley regulator with a bypass/return #12-803 or 12-804, both will work cheaply with rebuildable parts for under 10 bucks forever. if to use the 4-7 psi pump, which is still too much for the dainty hitachi, the bypass on regulator will not be needed and I can use the low pressure pump spring in regulator, also leaving an opening for a guage. the FI pumps will need the return line, not a problem, I just won't have an opening on the regulator. I am certain now any pump is compatible. I am also stopping another ridiculous engineered thought that pulsating pumps were necessary for carbs(the old soobs are one of few aside from usa that held onto that engineering for the year). Lastly, I live in a place where weather turns things upside down. (todays ice storm for example). the greatest benefit to FI was the high pressured pump. Now I can take advantage of that when nature makes fuel seem to be 3 tons a gallon to pump by placing regulator above the level of the carb mounted on a strut tower at much higher psi,responsive, airless, colder, compressing fuel... all this for 35 bucks +/- delivered by summit. I have 2 pumps here that weren't/aren't cheap like new or really are new, and want all options. Also, with spfi pump in, I will be setup for conversion as I have all the parts to do so (need a diagram for 93 2wd ECU). And that is what I am trying to do. my last 87 was a different car entirely and the icing on the cake was the flawless -23F start at 17 years old, on the slightly higher psi mystery pump . 4 is too much, and 3 is not enough. Hitachi has it tighter than a mouse fart, and I want to maximize it with regulator. Also, heat risers were unnecassary after maxxing fuel flow. I was hoping someone did this in this group. Years ago, I had heard of it done on the odd pressured soob (3.3), and never got details, except that it was an spfi soob going back to a carb- while using the high psi fuel pump that went with spfi.The only other thing I can think of is the return lines not being usable due to a clog. Original pumps were so close to the pressure need, the return line never got used. I am hoping I got it correct, will know soon enough. If there are any tips is why I posted. Link to comment Share on other sites More sharing options...
Hodaka Rider Posted January 2, 2007 Share Posted January 2, 2007 Or, you could again ignore how a carb'ed fuel delivery system actually works, and go of on your own whim. Link to comment Share on other sites More sharing options...
bgd73 Posted January 2, 2007 Author Share Posted January 2, 2007 Or, you could again ignore how a carb'ed fuel delivery system actually works, and go of on your own whim. That approach is not unusual to me, not just with soobs. In fact soobs are by far my proven favorite to leave alone. The only breakdown I have ever had was on a carbed subaru. And that was just once in 8 years The spfi did something I really liked fuel related, erasing all doubts. It had enough delivery for anything I wanted to do. Some older cars built for power even just slightly beyond oem like mine needed all the extras for fuel, and even oil. My soob is doing the same thing- all for a more powerful 90hp. :-\ I went through this once on my other 87, will do it again, a bit different with stuff I figured out. One more attempt at a question for the religious fsm people-- will 4psi regulator be too much even in conjunction with oem's regulator? I can experiment simple enough, maybe get it right first shot save me tme if someone knows. This whole thread would no doubt be interesting by the other fellow arctic tundra soob drivers with a carb... Link to comment Share on other sites More sharing options...
mikeshoup Posted January 2, 2007 Share Posted January 2, 2007 Unless the float bowl is emptying, I don't see how changing the fuel pressure will help. Link to comment Share on other sites More sharing options...
WoodsWagon Posted January 2, 2007 Share Posted January 2, 2007 This whole thread would no doubt be interesting by the other fellow arctic tundra soob drivers with a carb... Hardly.. Here's your "artic tundra" weather forcast: http://www.wunderground.com/US/ME/Brewer.html 45F and sunny on thursday! It's not even freezing out right now. Why not swap on the SPFI from your wrecked 2wd and be done with the carb? Link to comment Share on other sites More sharing options...
Hodaka Rider Posted January 2, 2007 Share Posted January 2, 2007 OK, one more time. I'm going to try to teach how carbs work. The fuel is delivered to the float bowl by the fuel pump. Once the float bowl is full, the float stops more fuel from coming in by closing the float valve, or needle valve. Increasing fuel pressure high enough will force the valve open and force more fuel into the carb, but it will most likely flood the engine as well. Fuel enters the intake manifold by being mixed with air in the carb. The air is drawn through the carb venturi at high speed, creating a vaccuum. This vaccuum is what draws the fuel through the jets in the carb - get it? The VACCUUM draws the fuel out of the float bowl, through the jets, where it mixes with the air, and then continues on down the manifold runners, past the valves, etc. Increasing your fuel pressure or volume on an otherwise stock engine (ie: one that works well with the stock carb in 99.9% of all cases) WILL NOT GIVE YOU MORE POWER. If you change the jets, you may get more power. If you put on a different carb, you may get more power. If you increase the horsepower potential of the engine substantially and are constantly running the float bowl dry (you aren't quite at that level - maybe add another 50-100hp) you might want to look at fuel delivery. And before you say it, the stock carb won't provide enough airflow to support that level of horsepower anyways. Please read this slowly until you understand. By the way, if you think you live in the "arctic tundra", you should try coming up here some time. I've seen weeks of weather way worse than you see, and physics still apply here. Link to comment Share on other sites More sharing options...
Hodaka Rider Posted January 2, 2007 Share Posted January 2, 2007 This whole thread would no doubt be interesting by the other fellow arctic tundra soob drivers with a carb... Again, I live way closer to tundra than you, and my carb'd Soob never needed any physics defying voodoo to run good. I understand how IC engines work, and maintained it accordingly. Link to comment Share on other sites More sharing options...
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