Boost referenced at the rails and return questions
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Boost referenced at the rails and return questions I'm have to get a boost referenced regulator and some fuel rails. I've been searching and can't really find out what I'm looking for.
When you use an external regulator, you have your input, your line to the rails and the return. My question is, if you use the stock supply line as the return,
1. how exactly is that done?
2. Is the evap line left untouched?
3. How do you supply the new say -8 line to the regulator?
4. What is modified when doing this?
When you use an external regulator, you have your input, your line to the rails and the return. My question is, if you use the stock supply line as the return,
1. how exactly is that done?
2. Is the evap line left untouched?
3. How do you supply the new say -8 line to the regulator?
4. What is modified when doing this?
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From: So.Cal.
The return line has to be larger diameter than the supply line, so you add a new line.
You have to connect the FPR reference to the intake manifold, so you may need a T fitting.
Also, you will have to edit your IFR table, it will now be flat (not sloped).
You have to connect the FPR reference to the intake manifold, so you may need a T fitting.
Also, you will have to edit your IFR table, it will now be flat (not sloped).
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From: Summerville, SC
As for the IFR table, what value would be used when the information is put into the spread sheet there are values that are given.
I'm have to get a boost referenced regulator and some fuel rails. I've been searching and can't really find out what I'm looking for.
When you use an external regulator, you have your input, your line to the rails and the return. My question is, if you use the stock supply line as the return,
1. how exactly is that done?
2. Is the evap line left untouched?
3. How do you supply the new say -8 line to the regulator?
4. What is modified when doing this?
When you use an external regulator, you have your input, your line to the rails and the return. My question is, if you use the stock supply line as the return,
1. how exactly is that done?
2. Is the evap line left untouched?
3. How do you supply the new say -8 line to the regulator?
4. What is modified when doing this?
In a quick - To use the stock feed as a return, you will need to run a new line (-8) and filter from the tank sending unit to aftermarket rails. A quick connect fitting will connect the -8 line to the sending unit. The return line will come off the fpr and will quick connect to your stock feed hard line. You will have to move the stock feed quick connect to the return side of the sending unit(stock fpr must be removed). Block T-block where the stock return line comes off of the feed line and ditch the stock return line. Don't forget to replace the stock filter since it will now flow in reverse.
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From: Summerville, SC
When you explain it, it makes sense. I appreciate that. What would be a sufficient amount of -8 from the tank to the rails? Also its crowded on the drivers side due to the crossover for the turbo. I wouldn't be against leaving the return and evap there, but the larger -8 line I'd rather run it on the passenger side. Has anyone done this?
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From: Summerville, SC
Any reason not to run the feed up the passenger side? The line would have to run the same direction initially and the wrap around the tank. I don't have any exhaust, just a dumped downpipe.
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Verdad Gallardo I don't see that it would be a problem. Just may take some longer line. The shorter the line the better though but I don't think it would matter much if we're talking just a few more feet. The shorter the line, the less restriction/friction.
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From: Summerville, SC
To have a -8 supply line, you have to have a -8 quick connect right? I can only seem to find a -6. Anyone have a link to -8?
Also, maybe I'm a bit confused after looking at some peoples setups. How exactly do the lines run? I mean as far as from the tank to the motor and back to the tank. I cant tell if the feed goes to the rails first and then the regulator, back to the rails, and then return or whats going on.
Also, maybe I'm a bit confused after looking at some peoples setups. How exactly do the lines run? I mean as far as from the tank to the motor and back to the tank. I cant tell if the feed goes to the rails first and then the regulator, back to the rails, and then return or whats going on.
Last edited by 98Camarod; Jan 26, 2009 at 05:29 PM.
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From: So.Cal.
That sounds backwards. I've read several people supplying with -8 and use the stock feed as the return. I'm trying to figure out how its actually accomplished and what is done with the evap line.
As for the IFR table, what value would be used when the information is put into the spread sheet there are values that are given.
As for the IFR table, what value would be used when the information is put into the spread sheet there are values that are given.
The first cell (at vac=0) of the IFR is usually the right value for all cells across... but you should measure the rail pressure with the reference hose removed, the value measured goes into the spreadsheet, and the resulting value in the first cell is the one.
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I forgot that my alternator has been relocated up top. I'm pretty sure there isn't enough room to have anything on that port of the rails. How would I route all the lines and have it function correctly, with having the feed coming up from the passenger side?
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Lonnie, is there any way you could give me some advice how I could run my fuel lines keeping in mind the relocated alternator? Theres only three ports available on the rails.
Also, I can't seem to find a price on your site for the 98 hotwire kit. I'd also like to get 20 ft of -8, associated regulator, and the necessary fittings. Do you think you could help me out?
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What I want to do is run a -8 line up the passenger side for a feed line and use the stock supply line as the return. I will need a boost referenced regulator, required fittings to hook up to the tank and return. I have some speed inc rails on the way. I will not be able to use the front passenger port on the rails because there isn't enough room due to the relocated alternator. Is that a problem or what can be done?
I do not think there is a quick disconnect fitting to convert to -8. I am using -6 feed and using the stock feed as a return as well. They make an fitting that is pretty much a compression fitting to convert your line to -6 to connect to your regulator.
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Heres a question for everyone. What is the value/values that go into the IFR table when using the boost referenced regulator?
I have 42.5lb injectors and a 2 bar map and I'll be running 58psi.
You will modify {EFILive B3701 (Injector pulse width voltage adjustment)} or {HPT Injector offset table} and {EFILive B4001 (IFR)} or {HPT Flow Rate vs. KPA} fueling tables. When using a referenced pressure regulator, you will put the same value all the way across/down in B4001. In B3701, use the value in the 0 row or column depending on which tuning software your using and copy it all the way down or across.