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Fuel system set up for boost, is this right?? Pic


Fuel system set up for boost, is this right?? Pic

Old 09-10-2011, 09:40 AM
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Old 09-10-2011, 10:16 AM
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Stock canister filter should be fine. IF they are 3/8NPT inlets and outlets. Don't be confused by that, as a 3/8 pipe tread female port, is a little bigger than 1/2" in actual size, might even be closer to 5/8, i forget. I dont see a problem going from a 3/8NPT male to a -8an or -10an fuel line. Try to stay away from 90* fittings, if you have to use a 90, use a full flow style 90.

A buddy of mine has a roots blower setup with twin 750 holleys. He has a 140GPH electric pump, plumbed with a stock merc mechanical pump, then a -8an single line feeding a fuel block, that goes to 3/8 hard lines to each bowl. Stock water seperators. I probably would have went with all -10 to the fuel block, but his works.

We can talk about this all day, but in the end, its better to go big or go home. Overkill on a fuel system is a good thing. Basically, if you want a reliable setup, and only want to do it once, start at the tank pickup, and work your way to the carb, elminating any questionable fittings, orifices, lines, etc, that "might" cause a problem.

You can put a fancy big dollar fuel pump in there, but if the tank pickups or anti-siphon valve are restricing it, you'll have problems. You can upgrade the stock fuel filters, with these, they are cheap money in the grand scheme.


I also believe, that you can plumb the bypass line from the regulater, back to the filter head. I would check with some of the other guys on that though.
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Old 09-12-2011, 09:29 PM
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You haven't told us which Bosch pump you are running. You only said it was a big one. We need more info. A quick Google only turns up the 200lph inline style pump. Give us a model number. Big difference if your pump will make 75gph at 5psi versus what it makes at 30 psi. Model number please.

Your boost reference line (the one you labelled vacuum) must tap into the BOX pressure, not the intake manifold. You've mentioned understanding this, but I'm just reiterating it. It's important.

You set the regulator pressure at 7psi with the reference line disconnected, and then you should be good to go once the line is hooked back up. Most all boost ref regulators are 1:1.

If you run your return line back into your fuel tank, then you don't have to worry about a fuel cooler. If you run your return line back to a tee in front of the fuel pump, then you can get the fuel too hot and vapor lock the pump on hot summer days. Your diagram shows that you are returning fuel all the way back to the tank, which is preferred.

You don't show your filter location.
Generally, you want to run the filter before the pump in order to protect it. You can, however, run it between the pump and regulator. DO NOT PUT A FILTER AFTER THE REGULATOR. The carb inlet screen is the only "filter" that should exist between the regulator and the carb.

Does your system flow enough fuel?
Buy a fuel pressure gauge. Tap the line going to the carb. Keep an eye on it. If the pressure stays where it should all the way to extended WOT, then the answer is yes. As filter gets obstructed, though, there is always the chance that it can drop so keep an eye on it.

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Old 09-13-2011, 07:15 AM
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I do not run the merc filter...its a water separator more than a filter I think..I run a large fram H/P
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Old 10-22-2011, 11:28 AM
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a couple good places for boost info is pontiaczone.com forced induction forums.


theturboforums.com which BTW has a marine section started.

I moderate the pontiaczone.com forced induction forums. Lots of great info and helpful people there its not just pontiac specific we have other makes there too.
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