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carburetion bog--- power valvle?
https://slantsix.org/forum/viewtopic.php?t=14472		 Page 1 of 1
Author:  argentina-slantsixer [ Thu Sep 22, 2005 9:57 am ]
Post subject:  carburetion bog--- power valvle?
Hey. Just sold my penin modified holley 2300 and "blueprinted" another one for me. Runs great BUT...

Tons of pep off the line, when the vacuumeter reachs kinda 10"HG it bogs bog bogs and wants to stall, the needle then drops to 5 and feels like somebody hit me from behind @ 70 mph, it goes like a thunder...

I'm guessing... too low power valvle rate? mine is 65 (I know, seems kinda low but was the onlyn one I had and wanted to get the car running today.

No black smoke so main circuits are cool (have to check that after a short cruise....) I have a 51 main jet on the passg side and a 57 on the drivers (to adress fuel distribution problems)

Also I enlargened the accel pump shooters.... "by eye" maybe I went too far and it's kinda squirting all the 30 cc too soon?

I know if I go richer on the mains I'd solve this but it's really nice on the low end, If I go rich enough to solve the 10"hg bog I'd ruin the off-the-line pep.... (been there)

idling @ 20-21 " Hg
in gear (d) 17" Hg

What should I run, a 10.5 valvle? a 8.5?
maybe you have another approach to this?
carb is a 2300 troats polished venturis slightly enlargened no problems whatsoever before 10"hg or after vacuum drops and power valvle kicks in.

Will post pix of my present setup, I had some cool idea for the kickdown (I'm using a lokar but I fabbed a spring loaded thing for having firm-firm shifts)
Author:  argentina-slantsixer [ Thu Sep 22, 2005 8:23 pm ]
Post subject: 
C'mon guys I need help, never had this kinda bog before...

I changed to a 8.5 and a 10.5 power valvles. Still the same. If you hit it hard off the line it will run like a champ, if you drive light too, but if you´re driving kinda slow and want to accelerate suddenly, the bog appears. Doesn´t stall though, just hesitates and then goes on real hard. Accel pump shooter may be crapped... throwing too much gas at once and then running outta reserve for li'l bit more open throttle pos.

I was thinking to run richer jets (say 55-55) but actually it feels like a rich mixture issue... I don´t know, idling and wotting acts like rich, middle acts like leaning out... no vac leaks at least idling... filter is open element (plain old cellulose style, no K&N) but I installed the fitting for keeping both hoses from my valvle cover, the PCV and the other...

Please help! I'm starting to regret having sold my great 2300 and I miss it....

Other thing: when I close one of the 2 needles it doesn´t stall... maybe idle circuits are wrong?
Author:  DusterIdiot [ Thu Sep 22, 2005 10:30 pm ]
Post subject:  We dont' need no stinkin vacc gauge...
at 10" you need some enrichment, the power valve won't open until the designated 6-7" so that leaves a big 3" window of lean-out...

Back off to 10.5 for power if that 'fixes' it you may want to see if an 8.5 works (if so it will be better for gas mileage than the 10.5...the 7.5 might be stretching things a bit).


Posts are kinda slow, if you drilled the shooter you will need to replace that thing with a size down ('28'?), and readjust the pump spring and possibly change the cam (I would rather use a smaller nozzle with a larger cam for more 'duration' of the 'shot' than run a large nozzle and a small cam which makes for a 'quick big gulp of gas'.

Your carb isn't an emissions carb with the reverse idle screws that richen the idle mix when crank 'in' is it?

good luck,

-D.Idiot
Author:  argentina-slantsixer [ Fri Sep 23, 2005 3:53 am ]
Post subject: 
News Update

Thanks DI for posting, I know you super-supersixed your slant before with a 2300.

This morning the car started right off with 3 pedal stomps, so I'm guessing that the accel pump is sending way too many gas.

I have the 10.5 power valvle now but the bog's still there, not when you really stomp on it or when you're nice, is when wanting to go kinda fast say from less than .2 trhottle to further open position.

I have a brown (????) cam and I'll try to track an original shooter

my carb ain't reverse idle screws.
Author:  DusterIdiot [ Fri Sep 23, 2005 4:09 am ]
Post subject:  Original engine?
If you have an original engine/ cam...with no real mods...


The 2300 should work with only:

'52' jets (correct them for your climate and elevation/etc...)

Red cam, or even the orange cam on #1... along with a '25' shooter...

retain the 10.5 PV...

start there and make improvements from that...


good luck,

-D.Idiot
Author:  argentina-slantsixer [ Fri Sep 23, 2005 6:38 am ]
Post subject: 
I have raised comp (not too much but anyway) steel gasket, headers with dual ex (balanced) the head is "speed ported" (meaning, lightly cleaned, not much material removed)

I think that the problem may be the accel pump shooter, someone reamed it bad ( :roll: who knows who... :wink: ) and now there's 2 thick streams of fuel going down the throats every time I touch the gas pedal. My plugs are black... :evil:

This carb I'm using is original equipment for our argentinian Slant Power RG 225 (the one that came with the RT version of my car) my cam is about the same as the RT (in fact, my whole engine is an RT, with some touches such as the comp ratio and slightly bigger cam whoops not that much) Original specs says jets 56-56 power valvle 6.5 shooter 23.... I was thinking 54-54 8.5 or 6.5 25 shooter... how that sounds?
Author:  argentina-slantsixer [ Fri Sep 23, 2005 4:53 pm ]
Post subject: 
Finally I dialed it in

Used 2 54 main jets, 23 accel pump shooter, mild cam and 65 power valvle. I advanced the time a li'l bit further, now she idles nice and has tons of pep. Cleaned out the plugs to see what happened and after a 30 min in town drive plugs are tan-brown (on the rich side but, duh! holley... hehe) I can't wait to take her on a road trip to see how she runs.

Many thanks to Duster Idiot!

Another important thing I learned is that if you use diffrent main jets you don't wanna have more than 1 or 2 numbers of diffrence, for some reason they throw all the balance to hell (I was running 50-57) now's better.

Has leaned out just abut right, now I need to choke it when cold starting for some minutes.
Author:  DusterIdiot [ Fri Sep 23, 2005 11:27 pm ]
Post subject:  Oh Wait!
:D


I shoulda quoted Dennis and said "Pull the Holley and throw in spitcan.."

LOL...

Glad to hear you got the carb 'back' into the sweet spot and know what tweaks you have left to get it 'right'.


keep us posted on how your drive went.

:wink:

-D.Idiot
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