car still diseling run on prob

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Yup, the metering block package is on it. It's still a good thing, and i second the 82s being fat. I'd drop tem down to somewhere around a 72 t start and see what she likes. Brownish is exactly what you want. Maybe a little carbon/soot on the thread area, and light tan on the ceramic and ground strap.
 
yes while idleing, seems I can still only get 8-9psi in gear
and yes on PCV
 
8-9 in gear is fine.

Don, there's quite a few guys doing that now. Smaller volume closed chamber heads and using quench... It's easy. I've run 10.8 with no issues at all when the engine's designed and built right to make use of it. And they need much less timing too.
 
Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
 
Babyblue66 said:
Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
Click to expand...

First of all a Holley with no metering block has a plate and you can't change the jets. Second of all, why Holley put PV's in the secondary metering blocks at all makes no sense at all on square bore carb. By the time your foot is in the secondaries, the vacuum is below the PV rating anyway and the secondary accelerator pump takes care of the transition. Third of all, my model # 4777 lists 71's and 76's respectively from the factory without a secondary PV. That's only a 5 size difference. Of course I'm speaking of square bore double pumper carbs only.

Care to debate? :-D Presently I'm running this carb (4777 with a Quickfuel throttle body) with 73 & 74 jets respectively on my build and all plugs look great! Every engine build will need to be jetted on an individual basis due to the myraid of configurations not only in the engine build itself but chassis weight, gearing, transmission, converter stall and altitude where the vehicle is being run. Jetting that is close to "square" is an indication of good fuel distribution and proper tuning. :)
 
ramcharger said:
First of all a Holley with no metering block has a plate and you can't change the jets. Second of all, why Holley put PV's in the secondary metering blocks at all makes no sense at all on square bore carb. By the time your foot is in the secondaries, the vacuum is below the PV rating anyway and the secondary accelerator pump takes care of the transition. Third of all, my model # 4777 lists 71's and 76's respectively from the factory without a secondary PV. That's only a 5 size difference. Of course I'm speaking of square bore double pumper carbs only.

Care to debate? :-D Presently I'm running this carb (4777 with a Quickfuel throttle body) with 73 & 74 jets respectively on my build and all plugs look great! Every engine build will need to be jetted on an individual basis due to the myraid of configurations not only in the engine build itself but chassis weight, gearing, transmission, converter stall and altitude where the vehicle is being run. Jetting that is close to "square" is an indication of good fuel distribution and proper tuning. :)
Click to expand...

I tuned my 670 street avenger in with a wideband af gauge and I have
68's in all 4 corners, runs awesome! Cruising at 14.5 and wot is 12.5
FWIW
 
baby, the manual secondaries have the valves or plugs dependign on the intended use. That's because the secondaries on those carbs open like primaries open... manually with your foot. So the carb has to compensate for the lean spots tipping the throttles brings. Hence the acclerator pump and PV. If the engine was in the higher rpms when the throttle was floored (like a loose convertor or two-step and clutch) then you could plug both power valve circuits and just use jetting. But there are too many "mid-throttle" conditions with most cars so you need that enrichment. Vacuum secondary carbs use the airflow thru the primaries to meter how fast the secondaries open. So that airflow is present. In fact, if you use too light a spring and get the VS bog.. it's because of the lack of airflow to pull fuel out the boosters. Theoretically you could add a PV circuit and help get rid of the bog in that situation.
 
Babyblue66 said:
Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
Click to expand...


why would that be that lean? theres people running 68s all the way around or 72s

maybe more help on this part would help
 
Babyblue66 said:
Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
Click to expand...

Alot of people claim this but in reality it depends on a few things as to what the jet split should be and it can vary from 1 jet size to 10 jet sizes. The power valve channel restrictors have an effect on the jet split. If your primary block has real small restrictors the split will be very little. If it has big restrictors the split can be alot. The high speed air bleed sizes also has an effect on jetting so if the air bleeds are way different on the primary and secondary sides there will be a bigger split. Then there's intake manifold fuel distribution which can even cause you to need different jet sizes on all corners to keep the mixture the same (or close) on all cylinders.
 
I have a problem now...when I took my carb spacer off. I have a loud whistle when I push the gas and the tach moves erratic vacc leak?
 
Isnt the spacer the same pattern as the carb base plate? Does it do it wirh the air cleaner on it? The erratic idle may just mean you need to re-tune the carb and mixtures. I'd expect it. But test with something flamable for a vacuum leak.
 
I fixed the idle.. I fixed the float level... and I found the squeal its the fan belt... I tighten it but it comes loose and squeals I have to find a way to tighten the alt. without it movind
 
Babyblue66 said:
Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
Click to expand...

Ok I realize this is not every carb and combo. Its just from my personal experience and from what I learned from a guy that has been tuning and racing for 20 years. Best way would be to have a o2 sensor in your exhaust. Or on a dyno.
 
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