3916-1S 950 cfm, long out of production, these were one of holleys less popular carbs but I think the reason had far more to do with the FLAWED (BIGGER IS ALWAYS BETTER) mentality of many of the users and not any fault in the carbs design.
I found the three barrel carbs worked exceptionally well once properly tuned, but as usually if you don't understand how to properly tune a carb its unlikely to run great out of the box.
I would not even bother using or testing these on anything under 454-540 cubic inches and 11:1 compression,
or without performance gearing and a cam, and serious race engine combo,
that is not designed to operate in the 4500rpm -6000 plus RPM range,
or something with a similar need to ingest a good deal of air flow,
but if you find one and the price is right it may surprise you,
if you take the time to tune it.
they had a common problem with running a bit lean in some cases at wide open throttle.
I've used several on 496 and 540 BBC builds with dual plane intakes and as long as you know how to tune they are not hard to get running really well.
Id say 70% of the guys I run into can,t tune, use a vacuum gauge timing light, find TDC or time an engine or read plugs or a fuel/air meter, adjust float levels, adjust valves or check fuel pressure or exhaust temps with an IR temp gun, even tuning a standard 750cfm Holley correctly seems beyond their skill level,
so if you hear that the 950 3 barrels difficult, to tune.... keep that in mind
worth reading
https://www.rodauthority.com/tech-stories/fuel-cooling/historic-holley-carburetor-milestones/
https://www.musclecardiy.com/tech-tips/complete-history-of-the-holley-carburetor/
basically this was a good idea that many people never quite got tuned correctly, they significantly increased the carbs flow potential by removing the divider in the rear two throttle bores to make a far larger cross sectional area with a large oval venturie, on the secondaries, this worked great PROVIDED you had a NEED for a good deal more air flow than the standard 780 and 750cfm carbs provide, the problem was mostly that the engines large enough to use that extra flow were far fewer than the guys purchasing and installing those three barrel carbs, so they got a un-deserved bad reputation.
you can hardly blame a component for failing to do its job if its used in an application where it can never reach its intended designed use.
theres lots of guys that had problems tuning those older Holley three barrel carbs, but I guess I was either lucky or had a bit more intuition, I loved my Holley three barrel carb on my 496 BBC engine when I used it and I got very good consistent results.
if youve got a need for a very effective large carb, your probably going to go with a DOMINATOR SERIES HOLLEY as those are current production,and an improved design, and have a bit more precise metering. but if you find an older three barrel in good condition for a good price its not only a decent option in my opinion, its got the advantage of having the same bolt pattern as the 750-850 Holley carbs so the standard intakes can be used plus flow rates similar to the dominators
http://www.summitracing.com/expertadvic ... Calculator
years ago I purchased two of these assortment packs when they cost about 1/2 the current price , Ive tried hard to keep 4 jets in each size in inventory as I use those, 72 jets in assorted sizes for $52 is still a good deal , and it gets better if you buy the pack or two of them, when summit posts a discount code
http://www.summitracing.com/parts/hly-36-181
IF you can read spark plugs , USE A TIMING LIGHT, and use an INFRARED TEMP GUN AND VACUUM GAUGE
http://www.harborfreight.com/cpi/ctaf/d ... mber=93547
A MULTI METER AND TIMING LIGHT WILL BE USEFUL
http://www.harborfreight.com/5-in-1-dig ... 98674.html
http://www.summitracing.com/parts/MSD-8991/
TUNING A HOLLEY IS DAMN SIMPLE
infrared thermometers are a very useful tool to track down issues with tuning, or mal functioning sensors
viewtopic.php?f=50&t=138&p=168&hilit=infrared#p168
Holley THREE BARREL
http://marketplaceadvisor.channeladviso ... &i=9738709
DOMINATOR
BTW just some info
the reason that tunnel ram intake was designed like that was that back when the holley dominator carburetors first came out , it was felt that a tunnel ram that allowed the carb to be bolted to the intake so that each carb throttle body venturie should feed each individual runner separately, that's why the lower intake plenum bolt spacing, matches the dominator bolt mount spacing, this in theory provides an individual runner intakes tunning advantages but the holley dominator throttle bore diameter is not large enough in cross sectional area to provide adequate flow rates for much over a 383 engine displacement in that config so a spacer plenum was quickly added to allow multiple throttle bores to supply each intake runner port entrance.
obviously the dominator carb model with the individually adjustable 4 corner idle screws was required, and theres 750 cfm,1050 cfm , 1150 cfm and 1250 cfm versions of the dominator carbs, and a direct 1:1 secondary throttle blade linkage kit that made each throttle open simultaneously was required
http://m.summitracing.com/search?keyword=dominator carburetor models
http://m.summitracing.com/search?keyword=dominator carburetor models&page=2
http://m.summitracing.com/search?keyword=dominator carburetor models&page=3
https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/20-5
obviously if the intakes set up for use as a single runner intake tuning the cam timing, exhaust scavenging and displacement to the engines compression and gearing and throttle bore size is critical to making it function effectively in the intended rpm range
USE THE CALCULATORS
http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php
I found the three barrel carbs worked exceptionally well once properly tuned, but as usually if you don't understand how to properly tune a carb its unlikely to run great out of the box.
I would not even bother using or testing these on anything under 454-540 cubic inches and 11:1 compression,
or without performance gearing and a cam, and serious race engine combo,
that is not designed to operate in the 4500rpm -6000 plus RPM range,
or something with a similar need to ingest a good deal of air flow,
but if you find one and the price is right it may surprise you,
if you take the time to tune it.
they had a common problem with running a bit lean in some cases at wide open throttle.
I've used several on 496 and 540 BBC builds with dual plane intakes and as long as you know how to tune they are not hard to get running really well.
Id say 70% of the guys I run into can,t tune, use a vacuum gauge timing light, find TDC or time an engine or read plugs or a fuel/air meter, adjust float levels, adjust valves or check fuel pressure or exhaust temps with an IR temp gun, even tuning a standard 750cfm Holley correctly seems beyond their skill level,
so if you hear that the 950 3 barrels difficult, to tune.... keep that in mind
worth reading
https://www.rodauthority.com/tech-stories/fuel-cooling/historic-holley-carburetor-milestones/
https://www.musclecardiy.com/tech-tips/complete-history-of-the-holley-carburetor/
basically this was a good idea that many people never quite got tuned correctly, they significantly increased the carbs flow potential by removing the divider in the rear two throttle bores to make a far larger cross sectional area with a large oval venturie, on the secondaries, this worked great PROVIDED you had a NEED for a good deal more air flow than the standard 780 and 750cfm carbs provide, the problem was mostly that the engines large enough to use that extra flow were far fewer than the guys purchasing and installing those three barrel carbs, so they got a un-deserved bad reputation.
you can hardly blame a component for failing to do its job if its used in an application where it can never reach its intended designed use.
theres lots of guys that had problems tuning those older Holley three barrel carbs, but I guess I was either lucky or had a bit more intuition, I loved my Holley three barrel carb on my 496 BBC engine when I used it and I got very good consistent results.
if youve got a need for a very effective large carb, your probably going to go with a DOMINATOR SERIES HOLLEY as those are current production,and an improved design, and have a bit more precise metering. but if you find an older three barrel in good condition for a good price its not only a decent option in my opinion, its got the advantage of having the same bolt pattern as the 750-850 Holley carbs so the standard intakes can be used plus flow rates similar to the dominators
http://www.summitracing.com/expertadvic ... Calculator
years ago I purchased two of these assortment packs when they cost about 1/2 the current price , Ive tried hard to keep 4 jets in each size in inventory as I use those, 72 jets in assorted sizes for $52 is still a good deal , and it gets better if you buy the pack or two of them, when summit posts a discount code
http://www.summitracing.com/parts/hly-36-181
IF you can read spark plugs , USE A TIMING LIGHT, and use an INFRARED TEMP GUN AND VACUUM GAUGE
http://www.harborfreight.com/cpi/ctaf/d ... mber=93547
A MULTI METER AND TIMING LIGHT WILL BE USEFUL
http://www.harborfreight.com/5-in-1-dig ... 98674.html
http://www.summitracing.com/parts/MSD-8991/
TUNING A HOLLEY IS DAMN SIMPLE
infrared thermometers are a very useful tool to track down issues with tuning, or mal functioning sensors
viewtopic.php?f=50&t=138&p=168&hilit=infrared#p168
Holley THREE BARREL
http://marketplaceadvisor.channeladviso ... &i=9738709
DOMINATOR
BTW just some info
the reason that tunnel ram intake was designed like that was that back when the holley dominator carburetors first came out , it was felt that a tunnel ram that allowed the carb to be bolted to the intake so that each carb throttle body venturie should feed each individual runner separately, that's why the lower intake plenum bolt spacing, matches the dominator bolt mount spacing, this in theory provides an individual runner intakes tunning advantages but the holley dominator throttle bore diameter is not large enough in cross sectional area to provide adequate flow rates for much over a 383 engine displacement in that config so a spacer plenum was quickly added to allow multiple throttle bores to supply each intake runner port entrance.
obviously the dominator carb model with the individually adjustable 4 corner idle screws was required, and theres 750 cfm,1050 cfm , 1150 cfm and 1250 cfm versions of the dominator carbs, and a direct 1:1 secondary throttle blade linkage kit that made each throttle open simultaneously was required
http://m.summitracing.com/search?keyword=dominator carburetor models
http://m.summitracing.com/search?keyword=dominator carburetor models&page=2
http://m.summitracing.com/search?keyword=dominator carburetor models&page=3
https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/20-5
obviously if the intakes set up for use as a single runner intake tuning the cam timing, exhaust scavenging and displacement to the engines compression and gearing and throttle bore size is critical to making it function effectively in the intended rpm range
USE THE CALCULATORS
http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php
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