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Old 01-08-2003, 05:31 AM
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Cliff R Cliff R is offline
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Just some more q-jet stuff. Received two "remanufactured q-jets this week for rebuilding/recalibration. The quality just gets worse and worse. Both were rejected and unmolested cores substituted instead. What we're seeing is more and more mass production on remanfactured carbs. The calibrations are out to lunch, even if they held fuel and worked correctly. It is beyond me to understand this as they supposedly use very expensive flow testing equipment to make sure the calibrations are within spec. Anyhow, I attached a photo of one of the carbs. Difficult to tell from the photo but this carb has many problems. For starters the fuel inlet seat has been drilled out and a very restrictive unit installed with two "O" rings. All of the main airbleeds have been removed/replaced, one of them was missing and no doubt went thru the engine, good thing it's made of brass! The idle airbleeds have been plugged in the airhorn (difficult to see in the photo of the airhorn) and the main casting drilled from just above the idle channel restriction into the primary main bores (same design as later production q-jets). The jets/rods are generic and not marked. The jets measure .072", the rods .043". With the small .050" main body and airhorn airbleeds this calibration would be well on the rich side. I suspect they stay rich rather than lean to have less customer complaints of surging and poor accelleration. The feed holes leading the the wells for the secondary tubes are near .060". This would have a lot of fuel flowing into the secondaries at full throttle as the wells stay full. The idle bypass air in the main body is plugged off with lead. An aluminum plug is over the accl pump check ball, not sure why? One of the secondary fuel supply tubes is smashed, barely visible in the photo. They hacked pretty hard on the secondary airflap shaft to remove the staked screws. The main casting in the photo failed the leak test at all 4 bottom plugs despite their attempt to dab epoxy over them.

The main reason we are seeing this type of work boils down to time and money. Companies that remanufacture carbs are trying to stock as few parts as possible and cut down on the number of steps required to get a finished product. In addition, they are trying to cover as many applications as possible with a single carb. I would suspect the fact that fewer and fewer older carbureted vehicles are still in use. These companies are probably seeing considerably less orders these days and trying to spend as little time/funds as possible. Personally, the reason(s) matter not. It is not ethical to deliver a product of this quality to anyone for any reason. At a minimum it should work as good as or better than the original.....Cliff
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File Type: jpg Mvc-003s.jpg (23.0 KB, 226 views)

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https://cliffshighperformance.com/
73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
  #2  
Old 01-08-2003, 05:31 AM
Cliff R's Avatar
Cliff R Cliff R is offline
Ultimate Warrior
 
Join Date: Nov 2000
Location: Mount Vernon, Ohio 43050
Posts: 18,000
Default

Just some more q-jet stuff. Received two "remanufactured q-jets this week for rebuilding/recalibration. The quality just gets worse and worse. Both were rejected and unmolested cores substituted instead. What we're seeing is more and more mass production on remanfactured carbs. The calibrations are out to lunch, even if they held fuel and worked correctly. It is beyond me to understand this as they supposedly use very expensive flow testing equipment to make sure the calibrations are within spec. Anyhow, I attached a photo of one of the carbs. Difficult to tell from the photo but this carb has many problems. For starters the fuel inlet seat has been drilled out and a very restrictive unit installed with two "O" rings. All of the main airbleeds have been removed/replaced, one of them was missing and no doubt went thru the engine, good thing it's made of brass! The idle airbleeds have been plugged in the airhorn (difficult to see in the photo of the airhorn) and the main casting drilled from just above the idle channel restriction into the primary main bores (same design as later production q-jets). The jets/rods are generic and not marked. The jets measure .072", the rods .043". With the small .050" main body and airhorn airbleeds this calibration would be well on the rich side. I suspect they stay rich rather than lean to have less customer complaints of surging and poor accelleration. The feed holes leading the the wells for the secondary tubes are near .060". This would have a lot of fuel flowing into the secondaries at full throttle as the wells stay full. The idle bypass air in the main body is plugged off with lead. An aluminum plug is over the accl pump check ball, not sure why? One of the secondary fuel supply tubes is smashed, barely visible in the photo. They hacked pretty hard on the secondary airflap shaft to remove the staked screws. The main casting in the photo failed the leak test at all 4 bottom plugs despite their attempt to dab epoxy over them.

The main reason we are seeing this type of work boils down to time and money. Companies that remanufacture carbs are trying to stock as few parts as possible and cut down on the number of steps required to get a finished product. In addition, they are trying to cover as many applications as possible with a single carb. I would suspect the fact that fewer and fewer older carbureted vehicles are still in use. These companies are probably seeing considerably less orders these days and trying to spend as little time/funds as possible. Personally, the reason(s) matter not. It is not ethical to deliver a product of this quality to anyone for any reason. At a minimum it should work as good as or better than the original.....Cliff

__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran!
https://cliffshighperformance.com/
73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
  #3  
Old 01-08-2003, 05:50 AM
Cliff R's Avatar
Cliff R Cliff R is offline
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Join Date: Nov 2000
Location: Mount Vernon, Ohio 43050
Posts: 18,000
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Sorry for the photo, not sure what happened during the loading process?
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__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran!
https://cliffshighperformance.com/
73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
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