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Fuel Pressure Regulator...??? Help

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Sonic Silver View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 8:47pm
Originally posted by javtopgun javtopgun wrote:

Oh , im running a 5-9 psi elec fuel pump gauged at carb also . . Two things things in common , 5-9 pressure fuel pump and 280 comp cam ??? but i know i have a wobble dis. shaft tho !
I thought that the Edelbrock and Carter AFB weren't supposed to run but 4 or 5 pounds of fuel pressure.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote javtopgun Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 8:56pm
Maybe so , but when i had a 4 to 7 electric fuel pump on it , it would die out at stop lights and was a bear to start .... like 5 mins sitting there till it would kick over. only in gear ... not at idle .. this one i have no issue at all .. in fact my park/nutral idle is 875 / 900 and in gear idle is 750 .. the old fuel pump was at 1000 park /nutral and 600 in gear .  Not good !! large diff 400 r's and always died out . cant carry 1200 idle park / nutral to get 750/ 800 in gear idle . 
1968 Javelin SSt 343ci semi restomod .
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Post Options Post Options   Thanks (0) Thanks(0)   Quote javtopgun Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 9:09pm
Also i had a AVS 2 edlebrock on the 343 and believe it or not it ran even worse , low end top end and idles .. That carb on this build was junk !! tried 2 other carbs also ran very bad .... the only carb that runs half way good is this 343 build was a stock 53 year old AFB .. with a elderbrock power valve ... No way i can tell why ... it just dose !! its not even rebuilt , just cleaned and found the power valve was almost wore out and replaced !  it has or had 52,000 miles on it . Like i said i now have a weber kit to rebuild it but why fix something that works at present !
1968 Javelin SSt 343ci semi restomod .
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 9:17pm
With too much fuel pressure, the needles move out of their seats and they can drip fuel at idle and flood out.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 9:25pm
Originally posted by javtopgun javtopgun wrote:

Also i had a AVS 2 edlebrock on the 343 and believe it or not it ran even worse , low end top end and idles .. That carb on this build was junk !! tried 2 other carbs also ran very bad .... the only carb that runs half way good is this 343 build was a stock 53 year old AFB .. with a elderbrock power valve ... No way i can tell why ... it just dose !! its not even rebuilt , just cleaned and found the power valve was almost wore out and replaced !  it has or had 52,000 miles on it . Like i said i now have a weber kit to rebuild it but why fix something that works at present !
Edelbrock/Carter have step up springs and pistons that serves the same purpose as the power valve that Holley uses.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote javtopgun Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 9:36pm
Ok but as i said when i had a LOWER pressure fuel pump 4-7 is when it died out .. the HIGHER pressure fuel pump 5-9 i have had ZERO issues with die out and a mush better range park idle vs in gear idle ,, Lower pressure i had a 400 rpm diff in gear /in park.. higher pressure i have less than 200 rpm diff. in gear in park .    
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 73hornut Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 10:27pm
Originally posted by javtopgun javtopgun wrote:

Ok but as i said when i had a LOWER pressure fuel pump 4-7 is when it died out .. the HIGHER pressure fuel pump 5-9 i have had ZERO issues with die out and a mush better range park idle vs in gear idle ,, Lower pressure i had a 400 rpm diff in gear /in park.. higher pressure i have less than 200 rpm diff. in gear in park .    
Remind us what your problem is?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote javtopgun Quote  Post ReplyReply Direct Link To This Post Posted: Sep/14/2021 at 11:02pm
no no no this is brothebamc tread im just saying i have same issue as he has ... but i have found i have a wobble dis. shaft i believe is my issue .... but mentioned that we , brotheb and i have 2 things in common tho he has a 401 and i have a 343 ,, we both have same cam and we both use a 5-9 pressure electric fuel pump . sonic and i were just having a conversation on fuel pumps and carbs  ...  brotheBamc has chuncky idle at start up and a chuncky low throttle up to 2000 rpms then all go's away. Which i have too . but his set up is alot diff than mine . was just odd we have same thing with 2 things in common ..  
1968 Javelin SSt 343ci semi restomod .
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Sep/15/2021 at 2:55pm
BrotherBamc - No parts needs replace, just re-adjusted.
I'd dis-assemble, inspect, check, re-assemble, bench set.
Chapstick liquidfied between fingers on gaskets.
Carb stood upright on-end mid-ranging "slop" when installing, tightening, bowl & block screws.
Accelerator pump arms screws intentionally too short so as not to effect above mid-ranging.
There's a LOT of "play" how a holley bowl & block meet the main body, and each other.
Squared front and centered on all that this way or that "shift on the slop" that's possible.
Lines everything up better internally possibly, would it not ?

Anyway, ain't gonna hurt nothin' to try this.
If it's 4-corner idle I reckon you're gonna need ( 4 ) pieces instead of ( 2 )
of basically wire brush bristle wire and only about oh 3/16" or 1/4" long.
A slight bend in the center, and they get inserted in your existing metering blocks.
they hold them self in, and REDUCE THE SQUARE INCHES OF AREA of the IFR...
The IFR is the Idle Circuit Fuel Jet.
You can "UN-DO" what adding the WIRES does TO THE IDLE BECAUSE...
You just open the Idle Mixture Screws MORE to deliver more VOLUME of Idle Emulsion.
BECAUSE the Idle Mix screws were only at say 1 turn opened...
SO... now the IDLE mix screws will be at 1.5 turns opened...
and now the carb is doing the same at idle as it was before...
BUT now the TRANSFER SLOT DISCHARGE will be RUNNING LEANER
because of those ~.010 dia pieces of wire in all the IFR's, and because
TRANSFER SLOT DISCHARGE is NOT effected by the Idle Mixture Screws.
It's that 1,400 to 2,000 rpm range man where all the normal drivin' happens.
That's all happening on the TRANSFER SLOTS is what's being proposed.
Then the Accelerator Pumps get tuned to cover the critical TRANSITION to MAIN CIRCUIT, ...
And the Main Circuit is unchanged by the Wires in the IFR's, only the cruise is.

Go thru it, put .010 wires in the IFR's, re-assy, Bench set it, and roll the dice ?
Most helpful info would be if ya can pin gauge the diameter of the existing IFR's and everything else.
Unless the carb you have has the "trick" #6-32 drilled brass set screw
"Transfer Slot Jet" feature, which is a pretty cool feature and somewhat easy to do.  Peace
Oh, consider Plumb a regulator & a fuel pressure gauge, confirm steady proper fuel pressure.






Edited by PHAT69AMX - Sep/15/2021 at 3:20pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Sep/16/2021 at 2:12pm
BrotherBamc - here's one good way to plumb a dual feed Holley using a Regulator
and bonus, misses the stock AMC Coil mounting location.
Plumbing Kit with Regulator available on eBay ( self made brkt in posted pic )
https://www.ebay.com/itm/202916919129?hash=item2f3eca7759:g:LXsAAOSw0fFbcwJd




Edited by PHAT69AMX - Sep/17/2021 at 1:24pm
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