Question about Fuel Return systems.
10-09-2007, 07:49 AM
#41
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sharif, im at a deciding point. I want to up the power, but i also want to up my safety factor.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
10-09-2007, 09:35 AM
#42
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Originally Posted by CUxtopher
sharif, im at a deciding point. I want to up the power, but i also want to up my safety factor.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
10-09-2007, 10:09 AM
#43
Originally Posted by CUxtopher
sharif, im at a deciding point. I want to up the power, but i also want to up my safety factor.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
Its either do a cjm rfs, exhaust, 3.12 pulley, plenum spacer and retune
or
see what it would cost to have a built short block swapped(while the block is out, how much to add cams/headers?)
after your RFS explanation at the shop, it all made sense. Consistency, predictability and less strain on the fuel system.
10-09-2007, 05:11 PM
#44
FMUs and boost referenced fuel pump voltage boosters are not free, why not invest the money into doing it right rather than ghetto rigging it?
return fuel systems offer plenty of advantages.
you dont overwork the pump by sending it more voltage than it was engineered for, increasing reliablilty.
you dont increase its work load by making it force 100psi into the rails, and the less load on the pump the more it will flow increasing overall capacity of the pump at any given voltage.
return fuel systems run you a parallel plumbing solution which promotes equal fuel pressure distribution as you start to reach flow capacity of your system, which in-turn promotes even cylinder tuning. uneven cylinder tuning will not show up on your wideband which only averages the cylinders on the bank its reading from.
the factory fuel rails are run inline, with a tiny little metal tube feeding the drivers side rail off the end of the passenger side rail. inline plumbing is already bad enough, but when you have a tiny little tube connecting the 2nd rail inline, chances are very high that you will experience a pressure drop across the system, limiting overall output and completely throwing off cylinder distribution. you can band-aid around this as well by tuning the car overly rich so that the leanest cylinders are safe while the richer cylinders are washing out the rings.
a return fuel system is a self contained solution that only depends on the pump and regulator functioning properly. adding voltage boosters and fuel pressure risers increase risks in reliability and risks in consistency by adding additional components that your tune is RELYING on.
overall, its a cleaner and OEM style solution that keeps every single component operating with-in its engineered environment. FMUs and voltage boosters are cheapo band-aids, and i recommend them only for temporary use. yes, they definately cram more fuel thru your injectors, so YES, you can make all the power in the world using them. that doesnt mean they arent crap. OEM cars do not use voltage boosters, and OEM cars do not use 8-12:1 rising rate regulators.
as for the guy who said he has done "WELL OVER" 100 TT Z/G's, hahahaha. right.
return fuel systems offer plenty of advantages.
you dont overwork the pump by sending it more voltage than it was engineered for, increasing reliablilty.
you dont increase its work load by making it force 100psi into the rails, and the less load on the pump the more it will flow increasing overall capacity of the pump at any given voltage.
return fuel systems run you a parallel plumbing solution which promotes equal fuel pressure distribution as you start to reach flow capacity of your system, which in-turn promotes even cylinder tuning. uneven cylinder tuning will not show up on your wideband which only averages the cylinders on the bank its reading from.
the factory fuel rails are run inline, with a tiny little metal tube feeding the drivers side rail off the end of the passenger side rail. inline plumbing is already bad enough, but when you have a tiny little tube connecting the 2nd rail inline, chances are very high that you will experience a pressure drop across the system, limiting overall output and completely throwing off cylinder distribution. you can band-aid around this as well by tuning the car overly rich so that the leanest cylinders are safe while the richer cylinders are washing out the rings.
a return fuel system is a self contained solution that only depends on the pump and regulator functioning properly. adding voltage boosters and fuel pressure risers increase risks in reliability and risks in consistency by adding additional components that your tune is RELYING on.
overall, its a cleaner and OEM style solution that keeps every single component operating with-in its engineered environment. FMUs and voltage boosters are cheapo band-aids, and i recommend them only for temporary use. yes, they definately cram more fuel thru your injectors, so YES, you can make all the power in the world using them. that doesnt mean they arent crap. OEM cars do not use voltage boosters, and OEM cars do not use 8-12:1 rising rate regulators.
as for the guy who said he has done "WELL OVER" 100 TT Z/G's, hahahaha. right.
10-10-2007, 01:54 PM
#45
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Originally Posted by phunk
as for the guy who said he has done "WELL OVER" 100 TT Z/G's, hahahaha. right.
I just hate when people jump to conclusions when you basically don't know any facts in what you are "concluding".
10-10-2007, 05:24 PM
#49
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Originally Posted by SpoilsofWar
Still waiting to hear details of how a reliable 750whp Z is possible without a RFS.
Please, save me $1000, and explain.
Please, save me $1000, and explain.
10-10-2007, 05:25 PM
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Originally Posted by SpoilsofWar
Still waiting to hear details of how a reliable 750whp Z is possible without a RFS.
Please, save me $1000, and explain.
Please, save me $1000, and explain.
Once you've put enough work into the car to make 750whp then the $1000 is peanuts. And when you're making that much power, you certainly want the most consistent fuel delivery without question.
10-10-2007, 05:28 PM
#51
Originally Posted by taurran
I doubt anyone serious about making that kind of power would be asking the question...
Once you've put enough work into the car to make 750whp then the $1000 is peanuts. And when you're making that much power, you certainly want the most consistent fuel delivery without question.
Once you've put enough work into the car to make 750whp then the $1000 is peanuts. And when you're making that much power, you certainly want the most consistent fuel delivery without question.
10-11-2007, 08:11 AM
#53
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Originally Posted by SpoilsofWar
Still waiting to hear details of how a reliable 750whp Z is possible without a RFS.
Please, save me $1000, and explain.
Please, save me $1000, and explain.
It's called a dyno queen. If you take it to the track on a hot day and thrash it, No. 2 piston will be history and you'll have a new motor in your future.
10-11-2007, 12:14 PM
#55
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Although I do see the pros and cons to both returnless and return systems, I personally had a fuel return system on my car. I would like to point out at least one negative recourse of a return system. In a FI'ed car keeping the fuel in the car cool, is a big advantage to combat detination and power robbing heat that can occur by sending (and resending) all your fuel from your tank all the way up to through the heat soaked engine compartment and then back again untill all the fuel is not at an ideal tempature anymore. With a returnless system using a modified factory fuel rail system like on wa2good's track car there is no harm in going returnless as long as they can retain constant fuel pressure to all cylinders. They just might have something there. Smart fella's, that Jim Wolf and associats.
http://www.doubledown350z.com/car.htm
^^^^^ This car for one (not a dyno queen), I know gets trashed alot at high boost and in sweltering heat sometimes. No return line, and no problems.
Something to think about
Curts
Originally Posted by zzerotwosixty
It's called a dyno queen. If you take it to the track on a hot day and thrash it, No. 2 piston will be history and you'll have a new motor in your future.
^^^^^ This car for one (not a dyno queen), I know gets trashed alot at high boost and in sweltering heat sometimes. No return line, and no problems.
Something to think about
Curts
Last edited by ShamrockG; 10-11-2007 at 12:23 PM.
10-13-2007, 06:54 PM
#56
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Originally Posted by ShamrockG
Although I do see the pros and cons to both returnless and return systems, I personally had a fuel return system on my car. I would like to point out at least one negative recourse of a return system. In a FI'ed car keeping the fuel in the car cool, is a big advantage to combat detination and power robbing heat that can occur by sending (and resending) all your fuel from your tank all the way up to through the heat soaked engine compartment and then back again untill all the fuel is not at an ideal tempature anymore. With a returnless system using a modified factory fuel rail system like on wa2good's track car there is no harm in going returnless as long as they can retain constant fuel pressure to all cylinders. They just might have something there. Smart fella's, that Jim Wolf and associats.
http://www.doubledown350z.com/car.htm
^^^^^ This car for one (not a dyno queen), I know gets trashed alot at high boost and in sweltering heat sometimes. No return line, and no problems.
Something to think about
Curts
http://www.doubledown350z.com/car.htm
^^^^^ This car for one (not a dyno queen), I know gets trashed alot at high boost and in sweltering heat sometimes. No return line, and no problems.
Something to think about
Curts
So what fuel system does it have? The fuel rails can't be stock. The left bank will be starving for fuel. I don't know what you consider sweltering. I meant 102+ on a drag strip shifting at redline. I don't know about time attack but I'll admit it's not a dyno queen. Other than injectors and fuel pump, what has been done to the fuel system? I'd like to save 1000$ too.
10-13-2007, 07:22 PM
#57
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Originally Posted by zzerotwosixty
So what fuel system does it have? The fuel rails can't be stock. The left bank will be starving for fuel. I don't know what you consider sweltering. I meant 102+ on a drag strip shifting at redline. I don't know about time attack but I'll admit it's not a dyno queen. Other than injectors and fuel pump, what has been done to the fuel system? I'd like to save 1000$ too.
Curtis
10-13-2007, 08:19 PM
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It only took me one second to blow my motor. No.2 cylinder ran lean and melted, and I only had 390 whp. A bigger crossover would help but it will not prevent deadheading at the end of the fuel rail. I don't have the time or money to keep changing engines.
10-13-2007, 09:14 PM
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Originally Posted by zzerotwosixty
It only took me one second to blow my motor. No.2 cylinder ran lean and melted, and I only had 390 whp. A bigger crossover would help but it will not prevent deadheading at the end of the fuel rail. I don't have the time or money to keep changing engines.
10-13-2007, 09:27 PM
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Just recieved my shortblock from GTM a few days ago. Probably take me two or three weeks to put it all back together. I'll need a bit of overtime before I get the return system though.