Author Topic: Fuel vaporizing issue  (Read 6553 times)

Offline cudabob496

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Re: Fuel vaporizing issue
« Reply #30 on: March 06, 2013 - 11:43:37 PM »
This little puppy handles my 850DP Holley and 600+ hp just fine. Pressure is a steady 6.5 psi,
with no regulator.

http://www.summitracing.com/parts/crt-m4862/overview/make/plymouth

if need regulator, this works good:

http://www.summitracing.com/parts/hly-12-803/media/images
« Last Edit: March 06, 2013 - 11:48:59 PM by cudabob496 »
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000




Offline BS CUDA

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Re: Fuel vaporizing issue
« Reply #31 on: March 06, 2013 - 11:48:09 PM »
This little puppy handles my 850DP Holley and 600+ hp just fine. Pressure is a steady 6.5 psi,
with no regulator.

http://www.summitracing.com/parts/crt-m4862/overview/make/plymouth


Yup - for now!! I ran that way just fine for awhile and then one day................ I now run with a bypass reg - 1/2" feed and 3/8" return.

Offline cudabob496

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Re: Fuel vaporizing issue
« Reply #32 on: March 07, 2013 - 12:47:57 AM »
Yup - for now!! I ran that way just fine for awhile and then one day................ I now run with a bypass reg - 1/2" feed and 3/8" return.

ya, I don't go to the track, just run on the street
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline ff6849

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Re: Fuel vaporizing issue
« Reply #33 on: March 30, 2013 - 10:18:57 AM »
update, installed the holley blue pump with return regulator, upgraded to a 3/8 supply line in-place of the 1/4 vapor return line using the old 5/16 supply line as my return. Pump is noticeably loud at idle but not at cursing speed. Car runs much better no more vaporization issues and it seems to have much better throttle response.   
(__________]]]]]}~~~~

73 440 Cuda'
915 heads (mild head work, stock bottom end 10/9:1 compression)
A518 2600-2800 Stall
4.10 rear gear
TTI headers with 3' exhaust with  X pipe 
comp XE274H cam
Hughes Roller Rockers
Holley Sniper EFI
Holley Street Dominator intake
MSD ignition

Offline brads70

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Re: Fuel vaporizing issue
« Reply #34 on: March 30, 2013 - 11:14:19 AM »
 :2thumbs:  Glad to hear you got it sorted out!
 I'm betting you will get sick of the noise of the Holley pump soon though. FYI the Mallory pump is MUCH quieter. :grinyes:
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0

Offline MEK-Dangerfield

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Re: Fuel vaporizing issue
« Reply #35 on: March 30, 2013 - 02:18:45 PM »

 I'm betting you will get sick of the noise of the Holley pump soon though. FYI the Mallory pump is MUCH quieter. :grinyes:

You won't even hear the Mallory fuel pump with the engine off.   :grinno:

Mike

1970 Challenger - SOLD
2016 SXT+.  1 of 524 SXT+'s in Plumb-crazy for 2016.

Offline msbaugh

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Re: Fuel vaporizing issue
« Reply #36 on: April 08, 2013 - 01:49:26 AM »
How do some of y'all run return lines with mechanical fuel pumps? Can you even run A bypass style regulator with the mechanical fp? I've just got the charcoal canister with my mechanical Holley pump. 3/8 feed- 1/4 return

Offline drewcrane

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Re: Fuel vaporizing issue
« Reply #37 on: April 15, 2013 - 08:22:40 PM »
How do some of y'all run return lines with mechanical fuel pumps? Can you even run A bypass style regulator with the mechanical fp? I've just got the charcoal canister with my mechanical Holley pump. 3/8 feed- 1/4 return

I have the same question , can and how can I run a return line with a factory mech. pump? in the past I have run a fuel iflter with two outlets and run one back to the tank m\but there has to be a more sanitary way if possible?

Offline cudabob496

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Re: Fuel vaporizing issue
« Reply #38 on: April 15, 2013 - 09:57:49 PM »
I have the same question , can and how can I run a return line with a factory mech. pump? in the past I have run a fuel iflter with two outlets and run one back to the tank m\but there has to be a more sanitary way if possible?

don't think you need it. You can buy the appropriate size mechanical pump to give you the 6.0 to 7.5 psi you need at your carb. And if you're
getting more than 7.5, you can add a cheapy Holley regulator for about $30.
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline drewcrane

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Re: Fuel vaporizing issue
« Reply #39 on: April 15, 2013 - 11:52:59 PM »
don't think you need it. You can buy the appropriate size mechanical pump to give you the 6.0 to 7.5 psi you need at your carb. And if you're
getting more than 7.5, you can add a cheapy Holley regulator for about $30.

Ok so run the factory set up ,with out a return line,see how it runs,and if I have issues hook up the return line,

or run the return line with the factory set up with a fuel filter with two outlets and see what my fuel pressure is .
 :dunno:

My biggest concern is vapor lock with the fuel here has 10% alcohol

Offline cudabob496

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Re: Fuel vaporizing issue
« Reply #40 on: April 16, 2013 - 04:41:02 AM »
Ok so run the factory set up ,with out a return line,see how it runs,and if I have issues hook up the return line,

or run the return line with the factory set up with a fuel filter with two outlets and see what my fuel pressure is .
 :dunno:

My biggest concern is vapor lock with the fuel here has 10% alcohol


I think if you run the line away from heat sources, you will be ok.
you can also insulate part of the line if necessary. I insulate the part
of mine that gets blasted with hotter air from the radiator. I have a gauge
inside my car similar to this:

http://www.summitracing.com/parts/atm-3361/overview/

« Last Edit: April 16, 2013 - 04:51:04 AM by cudabob496 »
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline drewcrane

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Re: Fuel vaporizing issue
« Reply #41 on: April 16, 2013 - 09:05:56 AM »
ok I will take your advice and do more of a factory set up and see how it does I can always add an electric pump later ,thanks for the help :2thumbs: