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Replacement 4 Carter BBD https://slantsix.org/forum/viewtopic.php?t=12620 |
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Author: | 440_Magnum [ Mon Apr 18, 2005 8:44 am ] |
Post subject: | Re: Other choice |
Quote: The holley 2280 was used on 318 equip trucks. I believe the year could be around 1976.(I can check if interested) It is fully interchangable except for a minor modification to the choke linkage.
Another important difference is the baseplate gasket. If you use a Holley 2280 basplate gasket on a BBD, it will block the vacuum to the choke pull-off and cause much cursing. I don't know if using the BBD baseplate on a Holley causes problems or not.Quote: I can say that a NEW holley 2280 clearly beats a leaky old BBD for idle and mileage
I'd take the leaky BBD, personally- I can FIX that. I have a 2280 that makes an excellent door stop or mud-dauber nest holder- but it never made much of a carburetor :p I only have it because we swapped my old BBD onto a friend's truck to get it to run.
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Author: | 440_Magnum [ Mon Apr 18, 2005 8:51 am ] |
Post subject: | |
Quote:
70 Valiants opinion on camshaft timing/ idle quality makes as much sense to me as yours....regardless of who he had dinner with.
This is something I still don't understand, just like I didn't understand it in the thread on heat risers. How can you have an opinion about math and physics? Its either true or false. Camshafts and idle characteristics are math and physics. You can certainly have an opinion on whether Carter carbs or Holley carbs are better overall because each have strengths and weaknesses and the relative importance you place on various characteristics might make one better for you and the other better for another. But in clear cases of "changing parameter X causes effect Y," opinion, per se, doesn't exist. |
Author: | steponmebbbboom [ Mon Apr 18, 2005 7:02 pm ] |
Post subject: | |
Quote: Yep, the 244°/244°/26° cam originated as a factory marine cam in the mid '60s
Really. I have heard that marine cams are usually setup for a lot more low-end torque to get the boat out of the hole faster, and if used in an automobile will show a sharp dropoff in power at high RPMs. They just used a standard automotive style grind even in the marine engines?
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Author: | 70survivor [ Mon Apr 18, 2005 9:39 pm ] |
Post subject: | |
How did a simple question about fuel mileage, rough idle, and low power degrade to such a caustic tirade about cams, and grammar? I value opinions based on personal experience. If the cam is the culprit at low idle, I can live with that. Right now, it doesn't seem to have enough power to get out of its own way. I know the BBD is bad about having vacuum leaks around the throttle shaft. What is the latest year the BBD was produced? If I need to replace this thing, then so be it. I have a thermostatic spring choke now and would prefer to leave it that way. |
Author: | steponmebbbboom [ Tue Apr 19, 2005 4:26 am ] |
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Threads often degrade to caustic tirades on their journey to the truth of the matter. We are people after all. I would prefer to see less of it but sometimes the means justify the ends. Often in a contest to be right each opponent will think out and research their posts more carefully and we all benefit. |
Author: | 440_Magnum [ Tue Apr 19, 2005 7:49 am ] |
Post subject: | |
Quote: . I know the BBD is bad about having vacuum leaks around the throttle shaft. What is the latest year the BBD was produced? If I need to replace this thing, then so be it. I have a thermostatic spring choke now and would prefer to leave it that way.
The BBD is no worse than any other carb about having loose bushings- its just that most BBDs saw a lot of years of service and the bushings wear out. (If I wanted to be caustic, I'd say that's because Holleys don't last long enough for the bushings to wear out before the driver gets disgusted and pitches the carb in the trash... ).Not sure when the last BBD was built, but the last one built was probably an electronic feedback carb for the 318 in 80s M-bodies, and you wouldn't want it anyway. There are carburetor restorers that will either knurl the existing bushings and re-finish them to fit, or install new bushings. I don't have any addresses handy, but several used to do business on the internet and/or by phone and shipping the carb to them. I think Dan used to have a place in Denver that did work for him, but maybe they're out of business now (Dan?) The truth is that any competent machine shop that was willing to take the time could do the re-bushing job, but talking one into doing it for less than a fortune might be a trick. |
Author: | SlantSixDan [ Tue Apr 19, 2005 10:09 am ] |
Post subject: | |
Quote: Really. I have heard that marine cams are usually setup for a lot more low-end torque to get the boat out of the hole faster, and if used in an automobile will show a sharp dropoff in power at high RPMs.
H'm. THis doesn't square with my understanding or experience. Most boats I've ridden in have had the engine operated at idle when started and warmed up, or at high speed when actually moving through water, with only very brief periods of low-RPM prop-drive operation while maneuvering around the docks, etc. The operating range of an automobile engine is quite a bit more variable (starts and stops, hills, highways, passing, etc.). THis would also seem to be why marine engines generally don't use vacuum advances (no point due to such limited part-throttle operation).For low-endy goodness, the '60-'64 passcar cam (232/228/8/0.375) would be the ticket, but it runs out of breath much above 3500RPM. |
Author: | steponmebbbboom [ Tue Apr 19, 2005 3:44 pm ] |
Post subject: | |
Quote: Not sure when the last BBD was built, but the last one built was probably an electronic feedback carb for the 318 in 80s M-bodies, and you wouldn't want it anyway.
The BBD was also used in the AMC 258 on the Jeep Wrangler into the early 90s and it had electronic mixture control that was controlled by the ECM. I wasnt too impressed with the one I rebuilt.Quote: The truth is that any competent machine shop that was willing to take the time could do the re-bushing job, but talking one into doing it for less than a fortune might be a trick.
Or talking one into listening to your instructions. It's not as simple as just drilling straight through the holes with a drill press and hammering in some bushings. I am still waiting for a refund on the carb J&J destroyed. "Q-Jets by Jim". Caveat emptor... |
Author: | 440_Magnum [ Tue Apr 19, 2005 3:51 pm ] |
Post subject: | |
Quote: Quote: Really. I have heard that marine cams are usually setup for a lot more low-end torque to get the boat out of the hole faster, and if used in an automobile will show a sharp dropoff in power at high RPMs.
H'm. THis doesn't square with my understanding or experience. Most boats I've ridden in have had the engine operated at idle when started and warmed up, or at high speed when actually moving through water, with only very brief periods of low-RPM prop-drive operation while maneuvering around the docks, etc. For purposes of discussion, lets consider "stock" inboard boat engines and not tweaked drag boats or anything like that. Boat engines spend most of their life running at wide-open throttle or near it, but the RPM is relatively low compared to cars- generally topping out around 3600-4000 RPM, depending on the engine and prop combination. And across that whole RPM range, the engine is loaded by the prop, so a fairly flat torque curve is desirable also. So a "boat" cam actually makes a nice, mild, torquey cam for a car. Quote: THis would also seem to be why marine engines generally don't use vacuum advances (no point due to such limited part-throttle operation).
That's more due to the fact that the designer can very accurately PREDICT what the load on the engine will be at any given RPM with a boat. You can't really lug a boat engine the way you can a car at low RPM in high gear, nor will a boat engine ever see vastly different throttle settings at the same RPM as a car would cruising at 65 on flat ground versus climbing a hill at 65. As long as the prop is in the water, the load on the engine is a very predictable function of RPM, and RPM is a predictable function of throttle setting. Yes, it varies a little with how fast the boat is moving, but really not nearly as much as you might think. All the "smarts" of the advance curve can be put right in the mechanical advance mechansim, no need to use vacuum to tweak the curve for the variation of load at a fixed RPM.
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Author: | Dennis Weaver [ Tue Apr 19, 2005 3:57 pm ] |
Post subject: | |
Quote: (If I wanted to be caustic, I'd say that's because Holleys don't last long enough for the bushings to wear out before the driver gets disgusted and pitches the carb in the trash... ).
No, you'd say that if you wanted to be right! D/W P. S. - 440_Magnum, czech your PM's!!!!! |
Author: | steponmebbbboom [ Tue Apr 19, 2005 4:00 pm ] |
Post subject: | |
Quote: Most boats I've ridden in have had the engine operated at idle when started and warmed up, or at high speed when actually moving through water, with only very brief periods of low-RPM prop-drive operation while maneuvering around the docks, etc. The operating range of an automobile engine is quite a bit more variable (starts and stops, hills, highways, passing, etc.). For low-endy goodness, the '60-'64 passcar cam (232/228/8/0.375) would be the ticket, but it runs out of breath much above 3500RPM.
This is all correct, but the unique problem marine engines face is that during acceleration a lot more torque is needed earlier on to get the boat onto the surface of the water and up to operating speed. This is due to the fact that water is much denser and creates much more drag or "rolling resistance" than a car has to deal with. The torque rise is sharper and ends at an earlier RPM. The peak HP is generally in the same area, but since many boats have only one speed, the engine needs more lowend grunt to get the hull out of the water. You can change your "gearing" per se by changing the propeller angle, and actually prop design is a science unto itself regarding anti-cavitation, progressive angle etc. Some of the larger ships have hydraulically variable prop angle, and others have a gearbox with a couple of forward speeds, but most are direct drive and use prop angle to determine "gearing". Using a marine cam in a car will give you a great hole shot, but the motor will be funny in that you wont get very much pull as you approach peak HP. All the torque rise happens down low. You want to get a prop that will give you the speed you want while keeping you at peak HP as much as possible. That 60-64 cam sounds alright for marine, since revving the piss out of the engine really isnt necessary if you have your prop set right. But you might find it boggy and slow to launch, unless you are racing and have a shallow prop pitch. The key is to get those revs up early.
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Author: | argentina-slantsixer [ Tue Apr 19, 2005 8:48 pm ] |
Post subject: | |
argentina's car had the 244° cam in all the 2 barrel "sporty" versions, and the dual pattern cam in all the 1 barrel applications, from 1961 to 1973. After that, they all used the 244 cam, whether the car was 1 or 2 barrel. all the slant six trucks had the passcar cam. We even had large trucks equipped with slants. As far as carburetion goes, I have to say that I like holleys cuz I understand them and I can't get carter parts down here. I still can find new whole trhottle assys for my holley 2300 for 20 US$, I know how to modify-clean etc all the passages to get what I want so I like my holleys cuz I never got along with carters. I guess that for some other people is the exact opposite. What I don't get is that I know and most of us knows that SSDan can be "rough" in some answers, even intolerant, he likes his grammar, and everything, but I don't think that he's aiming against anyone with his "polemic" grouchy posts. On the other hand, sandy, you're just attackin dan throwing $#!+ at him just for giggles. I think that you need to lighten and grow up and stop using the forum as your personal tool for trying to get into a pissing contest with a guy you ain't dig. That's disrespecting all other people whom are reading the post and wanna get actual info on FACTS, not your expert shrink opinion about dan's phsyc status or your "clever and sharp" intercourse with him. |
Author: | steponmebbbboom [ Tue Apr 19, 2005 8:58 pm ] |
Post subject: | |
I think something's been lost in the translation! |
Author: | Dennis Weaver [ Tue Apr 19, 2005 9:58 pm ] |
Post subject: | |
I got it! D/W |
Author: | argentina-slantsixer [ Wed Apr 20, 2005 5:07 am ] |
Post subject: | |
Quote: I think something's been lost in the translation!
yeah i'm not good even in spanish
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