A few weeks ago me and my friend(with a turbo crx) met some members from the 510 club by boundary road. I forget what their names were, but one guy was driving a blowthrough turbo green 510.
Anyways I was wondering how to convert the holley blue fuel pressure regulator to be referenced for boost?
Oh I ended up buying the innovate lm1 wideband. It is a great tool, I'm hoping to increase fuel mileage to 43mpg by leaning it out a little more.
Thanks
Brent
Green Turbo 510
RE: Green Turbo 510
Hi Brent, that was James and myself (Rob) in James' green car...
The Holley regulator has a diaphragm that's pretty close to 1 square inch so for every 1psi change in atmosphere, you get 1psi change in fuel pressure. The top half of the regulator (with the pressure adjustment) is inherently vented to the atmosphere, so if you put a box around your carb, then reference the regulator to that box, the fuel pressure delivered to the carb will always stay at some preset above box pressure.
To accomplish the mod, take out the pressure adjustment set screw and drill it through to accept a small fitting/extension piece to accept a piece of tube that runs to the carb's pressure box, then braze or solder or weld or glue (or bubblegum?) the fitting/extension into the set screw, and screw it back in and you are done. You might want to take a light skim pass on a mill to true up the top of the Holley regualtor to ensure that the jam nut has a flat surface to seat against (so it has a better chance of sealing now that you are running positive pressure into the top of it). It's not crucial to mill it, but in theory it's better; in reality if it is a little hissy, put a little dab of silicone seal on it.
Good work on the LM-1 unit. As you lean it out, it's a good idea to keep an eye on the exhaust temp as well to make sure it doesn't go silly high all of a sudden. Also, periodically pull the plugs out and have a look at them to make sure you don't have aluminum balling up onto them...
http://circletrack.com/techarticles/71898/
The Holley regulator has a diaphragm that's pretty close to 1 square inch so for every 1psi change in atmosphere, you get 1psi change in fuel pressure. The top half of the regulator (with the pressure adjustment) is inherently vented to the atmosphere, so if you put a box around your carb, then reference the regulator to that box, the fuel pressure delivered to the carb will always stay at some preset above box pressure.
To accomplish the mod, take out the pressure adjustment set screw and drill it through to accept a small fitting/extension piece to accept a piece of tube that runs to the carb's pressure box, then braze or solder or weld or glue (or bubblegum?) the fitting/extension into the set screw, and screw it back in and you are done. You might want to take a light skim pass on a mill to true up the top of the Holley regualtor to ensure that the jam nut has a flat surface to seat against (so it has a better chance of sealing now that you are running positive pressure into the top of it). It's not crucial to mill it, but in theory it's better; in reality if it is a little hissy, put a little dab of silicone seal on it.
Good work on the LM-1 unit. As you lean it out, it's a good idea to keep an eye on the exhaust temp as well to make sure it doesn't go silly high all of a sudden. Also, periodically pull the plugs out and have a look at them to make sure you don't have aluminum balling up onto them...
http://circletrack.com/techarticles/71898/
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sdubfid
Thanks Rob, I wish I had known about this before I went and spent $80 on a new regulator. I thought holley would advertise this since they could make more money off it.
By doing this will it only raise the fuel pressure under boost?? The old regulator I had would increase fuel pressure as there was less vaccuum which meant it was really rich at part throttle so I put a check valve in so it would only raise pressure under boost.
I'm most likely done with carbs on hondas for now. I gave in and bought a sohc vtec head.
By doing this will it only raise the fuel pressure under boost?? The old regulator I had would increase fuel pressure as there was less vaccuum which meant it was really rich at part throttle so I put a check valve in so it would only raise pressure under boost.
I'm most likely done with carbs on hondas for now. I gave in and bought a sohc vtec head.