Bypass fuel pressure regulator systems - Page 5

nhramnl · 11-30-2015, 01:28 PM

Oh, and by the way, I'm done talking about this now. As I said previously, I sought out the counsel of many helpful, experienced racers, both on and offline. I have received a number of responses and based on those responses, my specific combination and the price of the parts, plan to give the system a try. If in your opinion, I'm an idiot, take comfort in the fact that I'm spending my money, not yours. Thanks very much for weighing-in on the subject.

1320racer · 11-30-2015, 02:52 PM

Quote:

Originally Posted by nhramnl

nobody has ever said anything about a tenth and/or 1 MPH. If in your opinion, I'm an idiot, take comfort in the fact that I'm spending my money, not yours. Thanks very much for weighing-in on the subject.

Actually YOU did...

Quote:

Originally Posted by nhramnl

if the car picks up a tenth, I'll be a genius.

The reason why the unnamed "very recognized people in the sportsman ranks" are PMing you is because they can't defend their nonsense claims!

Next, if not a tenth/1MPH how much? Half a tenth and half a MPH? Doesn't matter, the addition of a bypass on your regulator makes exactly ZERO additional HP which means your car ain't running any quicker/faster than it's typical swing from pass to pass on any given day. Last, I never stated you're an idiot nor do I care what you do with your $, time and car.

buzzinhalfdozen · 11-30-2015, 03:15 PM

Some things never change....sad. Please allow the gentleman to do as he pleases with his car, making blanket statements about something of which you don't currently race is merely your opinion. I'm sure he is aware of your thoughts on the subject. I've had many PM's on different subjects for the exact reason we are seeing here.

1320racer · 11-30-2015, 04:32 PM

please inform me how offering advice on an internet forum stops anyone from doing what they want with their car.

MR DERBY CITY · 11-30-2015, 05:04 PM

Mr. 1320 racer, you have beat this subject to death....please go to Timeout. Regards, MJ.....

buzzinhalfdozen · 11-30-2015, 05:24 PM

Quote:

Originally Posted by 1320racer

please inform me how offering advice on an internet forum stops anyone from doing what they want with their car.

Ed, your advice and personal experiences were acknowledged by the OP. Leaving it there would have been a good idea, not calling folks out that may have messaged the OP to save the verbal aasaults. Just because someone doesn't share your views or ideas doesn't make them wrong or guilty of spreading "nonsense claims"...it's their advice or opinion. The possible difference being they chose not to argue about it on this forum. This over whelming urge to always be right and for your answer to be the only good one is what's led to your, shall we say sebatical from this site on more than one occasion.

1320racer · 11-30-2015, 06:07 PM

talk about what you know, not what you think you know. I had one short sabbatical from this site and Ken told me "it never should have happened"

Again, will somebody that claims they have improved their car's performance on the track by just adding this bypass to their regulator, please enlighten me how a pair of -3 hoses plumbed into a regulator makes additional HP, enough HP to run quicker and faster as evident on the time slip!

Thank you in advance.

Vic Santos · 12-05-2015, 10:38 PM

I really thought hard as to whether to post on this subject but I thought some might be interested in my findings:
During the first 2 to 3 seconds of a run using a Q-Jet, fuel pressure to the carb is never constant no matter what fuel system you have! During launch the Q-Jet inlet valve actually closes multiple times for as much as 1/4 of a second at a time. The reason is the fuel in the bowl is pushed to the back of the bowl (by G force) and that is where the float is. At the same instant the G force acts on the fuel in the line supplying the regulator causing the fuel pressure to the regulator to go down by 5 to 10 psi depending on the G force and the length of the fuel line. At the time the inlet valve closes there is NO FUEL FLOW through the regulator without a bypass. At that instant pressure ratio across the regulator is varying wildly and the regulator mechanism is trying to cope. This does not happen with a Holley, only the Q-Jet due to its small, single bowl and float design.
That being said, will you notice a difference with a bypass? Only if you have a extremely well set up Q-Jet and multiple data logged sensors. The best Q-Jet set up for launch typically is not the best for the rest of the race. A racing Q-Jet setup is always a compromise. You'll have to try it and see. But you should test different setups.
The best thing you can do for a Q-Jet is to make sure your fuel system can refill the bowl as soon as possible and the carb bowl is as large as possible.
BTW the above info is for system that has a regulated bypass from the pump discharge to the tank i.e. a big pump. The pump is putting out constant psi and flow but the carb never sees it until G loads are stabilized.

Adger Smith · 12-05-2015, 11:14 PM

Very good info Vic. & right on.. I've had a customer or two that we routed a long lead line from the regulator to the Q-Jet. We used the Leave G forces to feed the carb through the line. I had them mount the Regulator way forward and the line runs back to the carb. I also used a .035 secondary bypass from the Regulator output line to the main by pass line( back to tank) this bled all the air out of the regulator to the carb line. I feel it kept air/foam out of the float bowl.
It really works well with Q-jet and 2 bbl carbs that are used on dirt tracks.

nhramnl · 12-06-2015, 10:14 AM

Thank you very much for the excellent information, Vic. It is almost word-for-word the same information John Rademacher provided when attempting to convince me to buy the Product Engineering bypass regulator kit. At the risk of getting Ed Bigley stirred-up again, I will say that numerous other Q-jet racers have told me (in PMs) about findings very similar to Vic's. The bypass system "stabilizes" fuel pressure, particularly under high G-loads. Now, I will see if such stabilization translates to quicker 60-foot times, more consistent performance and improved ET and MPH. Thank you to all who responded. As I said in an earlier post, I will report my true and actual findings, once I get the car back out.

11-30-2015, 01:28 PM	#41
nhramnl Senior Member Join Date: Feb 2010 Posts: 504 Likes: 7 Liked 352 Times in 82 Posts	Re: Bypass fuel pressure regulator systems Oh, and by the way, I'm done talking about this now. As I said previously, I sought out the counsel of many helpful, experienced racers, both on and offline. I have received a number of responses and based on those responses, my specific combination and the price of the parts, plan to give the system a try. If in your opinion, I'm an idiot, take comfort in the fact that I'm spending my money, not yours. Thanks very much for weighing-in on the subject.

11-30-2015, 03:15 PM	#43
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 985 Likes: 0 Liked 12 Times in 9 Posts	Re: Bypass fuel pressure regulator systems Some things never change....sad. Please allow the gentleman to do as he pleases with his car, making blanket statements about something of which you don't currently race is merely your opinion. I'm sure he is aware of your thoughts on the subject. I've had many PM's on different subjects for the exact reason we are seeing here. __________________ Joe Buchanan SS/BX 3117

11-30-2015, 04:32 PM	#44
1320racer VIP Member Join Date: Nov 2007 Location: New Jersey Posts: 1,784 Likes: 71 Liked 403 Times in 194 Posts	Re: Bypass fuel pressure regulator systems please inform me how offering advice on an internet forum stops anyone from doing what they want with their car.

11-30-2015, 05:04 PM	#45
MR DERBY CITY VIP Member Join Date: Feb 2014 Location: Derby City, USA Posts: 3,334 Likes: 862 Liked 6,632 Times in 1,293 Posts	Re: Bypass fuel pressure regulator systems Mr. 1320 racer, you have beat this subject to death....please go to Timeout. Regards, MJ.....

11-30-2015, 06:07 PM	#47
1320racer VIP Member Join Date: Nov 2007 Location: New Jersey Posts: 1,784 Likes: 71 Liked 403 Times in 194 Posts	Re: Bypass fuel pressure regulator systems talk about what you know, not what you think you know. I had one short sabbatical from this site and Ken told me "it never should have happened" Again, will somebody that claims they have improved their car's performance on the track by just adding this bypass to their regulator, please enlighten me how a pair of -3 hoses plumbed into a regulator makes additional HP, enough HP to run quicker and faster as evident on the time slip! Thank you in advance. Last edited by 1320racer; 11-30-2015 at 06:46 PM.

12-05-2015, 10:38 PM	#48
Vic Santos Junior Member Join Date: Dec 2008 Posts: 26 Likes: 0 Liked 1 Time in 1 Post	Re: Bypass fuel pressure regulator systems I really thought hard as to whether to post on this subject but I thought some might be interested in my findings: During the first 2 to 3 seconds of a run using a Q-Jet, fuel pressure to the carb is never constant no matter what fuel system you have! During launch the Q-Jet inlet valve actually closes multiple times for as much as 1/4 of a second at a time. The reason is the fuel in the bowl is pushed to the back of the bowl (by G force) and that is where the float is. At the same instant the G force acts on the fuel in the line supplying the regulator causing the fuel pressure to the regulator to go down by 5 to 10 psi depending on the G force and the length of the fuel line. At the time the inlet valve closes there is NO FUEL FLOW through the regulator without a bypass. At that instant pressure ratio across the regulator is varying wildly and the regulator mechanism is trying to cope. This does not happen with a Holley, only the Q-Jet due to its small, single bowl and float design. That being said, will you notice a difference with a bypass? Only if you have a extremely well set up Q-Jet and multiple data logged sensors. The best Q-Jet set up for launch typically is not the best for the rest of the race. A racing Q-Jet setup is always a compromise. You'll have to try it and see. But you should test different setups. The best thing you can do for a Q-Jet is to make sure your fuel system can refill the bowl as soon as possible and the carb bowl is as large as possible. BTW the above info is for system that has a regulated bypass from the pump discharge to the tank i.e. a big pump. The pump is putting out constant psi and flow but the carb never sees it until G loads are stabilized.

12-05-2015, 11:14 PM	#49
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,352 Likes: 437 Liked 678 Times in 262 Posts	Re: Bypass fuel pressure regulator systems Very good info Vic. & right on.. I've had a customer or two that we routed a long lead line from the regulator to the Q-Jet. We used the Leave G forces to feed the carb through the line. I had them mount the Regulator way forward and the line runs back to the carb. I also used a .035 secondary bypass from the Regulator output line to the main by pass line( back to tank) this bled all the air out of the regulator to the carb line. I feel it kept air/foam out of the float bowl. It really works well with Q-jet and 2 bbl carbs that are used on dirt tracks. __________________ Adger Smith (Former SS)

12-06-2015, 10:14 AM	#50
nhramnl Senior Member Join Date: Feb 2010 Posts: 504 Likes: 7 Liked 352 Times in 82 Posts	Re: Bypass fuel pressure regulator systems Thank you very much for the excellent information, Vic. It is almost word-for-word the same information John Rademacher provided when attempting to convince me to buy the Product Engineering bypass regulator kit. At the risk of getting Ed Bigley stirred-up again, I will say that numerous other Q-jet racers have told me (in PMs) about findings very similar to Vic's. The bypass system "stabilizes" fuel pressure, particularly under high G-loads. Now, I will see if such stabilization translates to quicker 60-foot times, more consistent performance and improved ET and MPH. Thank you to all who responded. As I said in an earlier post, I will report my true and actual findings, once I get the car back out.