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Apr 1, 2006 | 02:04 PM

#31

tastyklair

Elder User

Joined: Jan 2004

Posts: 867

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From: Eastern Pa

Wait clark351. Don't say the lines are drawn yet. I'm not finished...blah blah blah

Apr 1, 2006 | 03:27 PM

#32

Bdox

Fleet Owner

Joined: Sep 2005

Posts: 28,609

Likes: 18

From: Lake Tahoe, Nevada

I wonder if Ferrite got his questions answered?

Apr 1, 2006 | 05:27 PM

#33

baddad457

Hotshot

Joined: May 2003

Posts: 11,141

Likes: 25

From: south louisiana

Quote:

Originally Posted by 1972FordCustom

here he says that he has never replaced a power valve and he dont know anyone that has, but in his last reply, he was talking about buying a holley and having to replace the power vavle...ummmmmmm interesting...

As grclark pointed out already, the rubber diaphram in the powervalve hardens after sitting too long and must be changed to have any hope of the carb functioning properly. This is the only reason I've ever had to change one, other than changing one due to it's being the wrong one for the application. I've also had more than my share of backfires and never had one blowout from it. I don't know where that rumor started, but it sure as hell wasn't from me.

Apr 2, 2006 | 10:04 AM

#34

BroncoChuck

Senior User

Joined: Mar 2006

Posts: 118

Likes: 0

From: yucca valley, CA

I would like to throw my two cents worth in here. I had a Holley under the hood of my Bronco for 3 years, and positively hated it. It ran PERFECTLY on flat, level ground. Huge power, fun to plant the heavy foot, etc. The problem came on severe hills and angles. Fuel spillover was a huge problem and my truck wouldn't run. More than once I had to roll down a rough stretch of trail backwards without power to get it level and running again. I went back to the motorcraft 2bbl for that reason. The only Holley I would ever put back in would be the truck avenger.

As for tuning problems or blown power valves I never had a single problem.

Apr 2, 2006 | 10:41 AM

#35

tastyklair

Elder User

Joined: Jan 2004

Posts: 867

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From: Eastern Pa

Before the days of the Avenger series Holley had a vent baffle add on that you could use to help stop fuel from sloshing out. It was intended for racers with either hard cornering as in roundy round guys, and severe accelleration as in the drags. Probably would have helped sideways trucks as well but that wasn't the intention back then.

Apr 2, 2006 | 10:56 AM

#36

baddad457

Hotshot

Joined: May 2003

Posts: 11,141

Likes: 25

From: south louisiana

They have jet extensions as well to prevent fuel starvation in the primary side on severe downhill grades too.

Apr 2, 2006 | 02:37 PM

#37

Torque1st

Posting Legend

Joined: Sep 2001

Posts: 30,255

Likes: 37

This discussion would be best in the carb forum but...

Both the Motorcraft and the Holley carbs were subject to power valve blowouts. Even a brand new power valve could be blown from a single backfire. I have personally experienced this dozens of times. It was a major pain to be tuning an engine and get a backfire then having to replace that $@$*#! power valve. That is the reason Holley introduced their check valve to prevent most (not all) blowouts. I made major amounts of cash at one time tuning carbs (and replacing power valves) for people, both Holley and Carter/Edelbrock. Both systems have their faults and strong points. For any kind of weekend performance or racing application I prefer to use Holley carbs because of their adaptability and accessories, but for a daily driver I prefer to use an Edelbrock. I have owned many types of carbs and I have worked on even more.

Apr 4, 2006 | 12:38 PM

#38

BroncoChuck

Senior User

Joined: Mar 2006

Posts: 118

Likes: 0

From: yucca valley, CA

I know this may cause even more controversy but, The BEST working off-road carb I have seen on the trails is the quadrajet. As much as it hurts me to say it, it runs smoothly on any angle, even when the blazer in question was laying on its side.