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[Datsun 1200 encyclopedia]

Choosing A Carburetor

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Category: Fuel System

Revision as of 04:48, 24 December 2011
ddgonzal (Talk | contribs)
(->Motorcyle Carbs)
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ddgonzal (Talk | contribs)
(->Weber IDF)
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[[Parts Reference]] [[Parts Reference]]
-== Which is better? Sidedraft or downdraft? ==+= Which is better? Sidedraft or downdraft? =
In a way, downdraft is very good and inexpensive -- all A-series engine come with a carburetor, so it's all ready to go. In a way, downdraft is very good and inexpensive -- all A-series engine come with a carburetor, so it's all ready to go.
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Think about [[Fuel Injection]], which can use the sidedraft carburetor manifold or factory Datsun parts. It's easier than most think. By removing the venturi required by a carburetor, maximum airflow and thus maximum horsepower can be obtained. See the main article [[Fuel Injection]]. Think about [[Fuel Injection]], which can use the sidedraft carburetor manifold or factory Datsun parts. It's easier than most think. By removing the venturi required by a carburetor, maximum airflow and thus maximum horsepower can be obtained. See the main article [[Fuel Injection]].
-[http://datsun1200.com/modules/myalbum/photo.php?lid=830 http://datsun1200.com/modules/myalbum/photos/thumbs/830.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1048 http://datsun1200.com/modules/myalbum/photos/thumbs/1048.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=44 http://datsun1200.com/modules/myalbum/photos/thumbs/44.jpg]+[http://datsun1200.com/modules/myalbum/photo.php?lid=830 http://datsun1200.com/uploads/thumbs/830.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1048 http://datsun1200.com/uploads/thumbs/1048.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=44 http://datsun1200.com/uploads/thumbs/44.jpg]
-= Carburetor Types =+= Single or Twin? =
-Carburetors commonly used on Datsun 1200s include '''Sidedraft''' and '''Downdraft''' types.+Which is better a single carb setup, or a twin-carb kit?
 + 
 +* Definitely the twin two-barrel gives best performance for a 4-cylinder engine. Twin Weber/Dellorto/Mikuni = 4 throttles.
 + 
 +* From a cost standpoint, single carburetors are better -- about half the cost
 + 
 +* For reliability consideration, single carburetor is superior. Most of the performance without the hassle
 + 
 +Contrary to what you might think, twin carbs don't give twice the airflow of single carbs -- because the twins are feeding one or two cylinders, they are only being used half the time.
 + 
 +With twin dual-throttle sidedrafts on an inline four cylinder, you get the extra advantage of a tuned-port intake path for each intake port. This is just like the individual tuned-port runners used in fuel injection, which is good for low-speed torque, and good for high-end power. Though few if any sidedraft manifolds use long runners, but are instead designed for higher rpm (short runners), the individual throttles still give good low speed torque.
= Downdrafts = = Downdrafts =
Line 32: Line 42:
Of course downdraft carbs of other brands can be used, but these are the popular ones. Of course downdraft carbs of other brands can be used, but these are the popular ones.
- 
== Stock Hitachi 306 == == Stock Hitachi 306 ==
Line 39: Line 48:
* best driveability e.g. smoothness of throttle response * best driveability e.g. smoothness of throttle response
-Although properly jetted and synchronized Webers may run just as well they will take some special tuning effort to equal this.+Although properly jetted and synchronized Webers can be made to run just as well, they will take some special tuning effort to equal this.
See the main article [[Carburetor Overview]]. See the main article [[Carburetor Overview]].
-[http://datsun1200.com/modules/myalbum/photo.php?lid=1008 http://datsun1200.com/modules/myalbum/photos/thumbs/1008.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=42 http://datsun1200.com/modules/myalbum/photos/thumbs/42.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=467 http://datsun1200.com/modules/myalbum/photos/thumbs/467.JPG]+[http://datsun1200.com/modules/myalbum/photo.php?lid=1008 http://datsun1200.com/uploads/thumbs/1008.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=42 http://datsun1200.com/uploads/thumbs/42.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=467 http://datsun1200.com/uploads/thumbs/467.JPG]
== Weber DGV 32/36 == == Weber DGV 32/36 ==
The Weber DGV series downdraft carb is an excellent choice for the daily driver stock or lightly modified A-series engine. See the main article [[Weber 32/36 Carburetor]]. The Weber DGV series downdraft carb is an excellent choice for the daily driver stock or lightly modified A-series engine. See the main article [[Weber 32/36 Carburetor]].
-Note that the Holley G180 and Holley 5200 are the same carburetor, as commonly found on Ford engines and others. These are made by Holley with a license from Weber of Italy.<ul><li>Least expensive upgrade choice</li><li>can use stock A-series engine manifold by using a simple adapter plate</li><li>Uses the Solex two-barrel bolt pattern</li></ul><p>[http://datsun1200.com/modules/myalbum/photo.php?lid=90 http://datsun1200.com/modules/myalbum/photos/thumbs/90.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=591 http://datsun1200.com/modules/myalbum/photos/thumbs/591.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=798 http://datsun1200.com/modules/myalbum/photos/thumbs/798.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=799 http://datsun1200.com/modules/myalbum/photos/thumbs/799.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=881 http://datsun1200.com/modules/myalbum/photos/thumbs/881.jpg]+Note that the Holley G180 and Holley 5200 are the same carburetor, as commonly found on Ford engines and others. These are made by Holley with a license from Weber of Italy.<ul><li>Least expensive upgrade choice</li><li>can use stock A-series engine manifold by using a simple adapter plate</li><li>Uses the Solex two-barrel bolt pattern</li></ul><p>[http://datsun1200.com/modules/myalbum/photo.php?lid=90 http://datsun1200.com/uploads/thumbs/90.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=591 http://datsun1200.com/uploads/thumbs/591.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=798 http://datsun1200.com/uploads/thumbs/798.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=799 http://datsun1200.com/uploads/thumbs/799.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=881 http://datsun1200.com/uploads/thumbs/881.jpg]
 + 
 +== Weber IDF ==
 +Downdraft carbs of exotic car fame
 + 
 +{{UploadPost|174_5c1d3d3b8f310.jpg|490218}} {{AlbumH|7256|jpg|224}}
 + 
 +IDF44s on F.E.T. manifold ([{{Post|490218}} more pics])
 +<br>{{UploadPost|174_5c1d3d288463c.jpg|490218}} {{UploadPost|174_5c1d3d49bb73e.jpg|490218}} {{UploadPost|174_5c1d3d6f893c5.jpg|490218}}
 + 
 +IDFs on A12GX manifold
 +<br>{{Album|16020}} {{Album|16018}} {{Album|16019}}
= Sidedrafts = = Sidedrafts =
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* [[Dellorto]] DHLA * [[Dellorto]] DHLA
* Solex ADDHE * Solex ADDHE
-* SK OER racing sidedraft+* SK [[OER]] racing sidedraft
== LHD Considerations == == LHD Considerations ==
-NOTE: Dual sidedrafts of the Weber/Mikuni-Solex/Dellorto type do not fit Left-hand-drive 1200s -- they will hit the brake master cylinders. Use Twin Hitachis, which fit, or you could move the Master Cylinder (see [[Remote Master Cylinder]]).+NOTE: Dual sidedrafts of the Weber/Mikuni-Solex/Dellorto type hit the brake master cylinder on LHD 1200s. [[Hitachi Twin Carb]] fits better, or you can use various means to make them fit.
- + See main article: [[LHD Sidedrafts]]
-B310:+
-<blockquote><hr>had a 77 210 with an a15. moved the motor one inch to the right so i could mount dual mikunis. no problems up to 125 mph.+
- +
-[http://forum.ratsun.net/showthread.php?t=9861 Ratsun]<hr></blockquote>+
== HJE38W Hitachi Twin Sidedrafts (GX engine carbs) == == HJE38W Hitachi Twin Sidedrafts (GX engine carbs) ==
These variable-venturi carbs are the factory setup for [[A12GX Engine|Datsun 1200 GX]] cars (twin SU-type Hitachis). Not sure if these are swappable with the SUs and Solex/Zenith-Stromberg carbs, but are of similar design. These were also fitted to the Bluebird 411 SS and SSS, 240Z/260Z, B110GX, B210GX, PE10, 180B SSS, P510 SSS, and 311 roadsters. These variable-venturi carbs are the factory setup for [[A12GX Engine|Datsun 1200 GX]] cars (twin SU-type Hitachis). Not sure if these are swappable with the SUs and Solex/Zenith-Stromberg carbs, but are of similar design. These were also fitted to the Bluebird 411 SS and SSS, 240Z/260Z, B110GX, B210GX, PE10, 180B SSS, P510 SSS, and 311 roadsters.
-Available in "dome-top" through 1972 and then "flat-top" versions in 1973 and up. Most use the 38 (38mm bore), but there are 46s on the 2000cc Roadster.<ul><li>Angled runner design is generally a plus, although the a-series heads don't have angled runners to match</li><li>continuously variable venturi design (slides)</li><li>single throttle is a minus, compared to the dual Weber DCOEs (four throttles total)</li></ul>[http://datsun1200.com/modules/myalbum/photo.php?lid=776 http://datsun1200.com/modules/myalbum/photos/thumbs/776.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1002 http://datsun1200.com/modules/myalbum/photos/thumbs/1002.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1003 http://datsun1200.com/modules/myalbum/photos/thumbs/1003.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=616 http://datsun1200.com/modules/myalbum/photos/thumbs/616.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1132 http://datsun1200.com/modules/myalbum/photos/thumbs/1132.jpg]+Available in "dome-top" through 1972 and then "flat-top" versions in 1973 and up. Most use the 38 (38mm bore), but there are 46s on the 2000cc Roadster.<ul><li>Angled runner design is generally a plus, although the a-series heads don't have angled runners to match</li><li>continuously variable venturi design (slides)</li><li>single throttle is a minus, compared to the dual Weber DCOEs (four throttles total)</li></ul>[http://datsun1200.com/modules/myalbum/photo.php?lid=776 http://datsun1200.com/uploads/thumbs/776.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1002 http://datsun1200.com/uploads/thumbs/1002.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1003 http://datsun1200.com/uploads/thumbs/1003.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=616 http://datsun1200.com/uploads/thumbs/616.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1132 http://datsun1200.com/uploads/thumbs/1132.jpg]
The Hitachis are tuned in a manner similar to SU carburetors. Here are links to tuning information: The Hitachis are tuned in a manner similar to SU carburetors. Here are links to tuning information:
Line 93: Line 109:
* [http://home.istar.ca/~datsun/att06.htm Datsun Service Manual SU] * [http://home.istar.ca/~datsun/att06.htm Datsun Service Manual SU]
-[http://datsun1200.com/modules/myalbum/photo.php?lid=229 http://datsun1200.com/modules/myalbum/photos/thumbs/229.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=619 http://datsun1200.com/modules/myalbum/photos/thumbs/619.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=955 http://datsun1200.com/modules/myalbum/photos/thumbs/955.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=960 http://datsun1200.com/modules/myalbum/photos/thumbs/960.jpg]+[http://datsun1200.com/modules/myalbum/photo.php?lid=229 http://datsun1200.com/uploads/thumbs/229.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=619 http://datsun1200.com/uploads/thumbs/619.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=955 http://datsun1200.com/uploads/thumbs/955.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=960 http://datsun1200.com/uploads/thumbs/960.jpg]
== Mikuni PHH == == Mikuni PHH ==
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<br>Reference: [http://www.bimmers.com/02/upgrades/engine.html bimmers.com] <br>Reference: [http://www.bimmers.com/02/upgrades/engine.html bimmers.com]
-[http://datsun1200.com/modules/myalbum/photo.php?lid=152 http://datsun1200.com/modules/myalbum/photos/thumbs/152.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=787 http://datsun1200.com/modules/myalbum/photos/thumbs/787.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=377 http://datsun1200.com/modules/myalbum/photos/thumbs/377.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=381 http://datsun1200.com/modules/myalbum/photos/thumbs/381.jpg]+ See main article: [[Mikuni PHH]]
 + 
 +[http://datsun1200.com/modules/myalbum/photo.php?lid=152 http://datsun1200.com/uploads/thumbs/152.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=787 http://datsun1200.com/uploads/thumbs/787.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=377 http://datsun1200.com/uploads/thumbs/377.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=381 http://datsun1200.com/uploads/thumbs/381.jpg]
Nissan Competition used to sell Mikuni jet parts. Nissan Competition used to sell Mikuni jet parts.
== Weber DCOE == == Weber DCOE ==
 + See main article: [[Weber DCOE carburetor]]
 +
The great thing about these carbs (as well the Dellorto DHLA) is that the jets are externally accessible, even when the air filter is on. This makes jet changes at the racetrack a snap. The great thing about these carbs (as well the Dellorto DHLA) is that the jets are externally accessible, even when the air filter is on. This makes jet changes at the racetrack a snap.
-These are available in 40, 42, 45, 48, 50, and 55mm sizes. Most Datsun A-series street engines run the dual 40s. Note that there are different size venturis for the 40s. This "barrel" size (40 or 45) doesn't determine the airflow, which is determined by the size of the main venturi (choke). The 28mm venturi might work best for a street A12, while a 38 venturi would be good for an 8,000 rpm A14. For single-carb installations, a bigger carb may be fitted.+These are available in 40, 42, 45, 48, 50, and 55mm sizes. Most Datsun A-series street engines run the dual 40s. Note that there are different size venturis for the 40s. This "barrel" size (40 or 45) doesn't determine the airflow, which is determined by the size of the main venturi (choke). The 28mm venturi might work best for a street A12, while a 38 venturi would be good for an 8,000 rpm A14.
-=== Single carb manifolds ===+'''Single carb'''
-[http://datsun1200.com/modules/myalbum/photo.php?lid=3461 http://datsun1200.com/modules/myalbum/photos/thumbs/3461.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=80 http://datsun1200.com/modules/myalbum/photos/thumbs/80.JPG][http://datsun1200.com/modules/myalbum/photo.php?lid=650 http://datsun1200.com/modules/myalbum/photos/thumbs/650.JPG] [http://datsun1200.com/modules/myalbum/photo.php?lid=3503 http://datsun1200.com/modules/myalbum/photos/thumbs/3503.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=7766 http://datsun1200.com/modules/myalbum/photos/thumbs/7766.jpg] +<br><img size=400>http://datsun1200.com/uploads/photos/3503.jpg</img> [http://datsun1200.com/modules/myalbum/photo.php?lid=3503 album]
 +<img size=400>http://datsun1200.com/uploads/photos/16231.jpg</img> [http://datsun1200.com/modules/myalbum/photo.php?lid=16231 album]
-==== Cannon ====+'''Dual DCOE'''
-[http://datsun1200.com/modules/myalbum/photo.php?lid=16231 http://datsun1200.com/modules/myalbum/photos/thumbs/16231.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=16232 http://datsun1200.com/modules/myalbum/photos/thumbs/16232.jpg] +<br><img size=400>http://datsun1200.com/uploads/photos/136.jpg</img> [http://datsun1200.com/modules/myalbum/photo.php?lid=136 album]
- +
- +
-==== Warneford ====+
-[http://datsun1200.com/modules/myalbum/photo.php?lid=16422 http://datsun1200.com/modules/myalbum/photos/thumbs/16422.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=16423 http://datsun1200.com/modules/myalbum/photos/thumbs/16423.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=16424 http://datsun1200.com/modules/myalbum/photos/thumbs/16424.jpg]+
- +
-=== Dual carb manifolds ===+
-* angled manifolds+
-* [http://datsun1200.com/modules/myalbum/photo.php?lid=133 http://datsun1200.com/modules/myalbum/photos/thumbs/133.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=15866 http://datsun1200.com/modules/myalbum/photos/thumbs/15866.jpg]+
- +
-* Tomei engine, good view of the linkage+
-*: [http://datsun1200.com/modules/myalbum/photo.php?lid=136 http://datsun1200.com/modules/myalbum/photos/thumbs/136.jpg]+
- +
- +
-[http://datsun1200.com/modules/myalbum/photo.php?lid=224 http://datsun1200.com/modules/myalbum/photos/thumbs/224.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=606 http://datsun1200.com/modules/myalbum/photos/thumbs/606.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=642 http://datsun1200.com/modules/myalbum/photos/thumbs/642.JPG][http://datsun1200.com/modules/myalbum/photo.php?lid=274 http://datsun1200.com/modules/myalbum/photos/thumbs/274.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=706 http://datsun1200.com/modules/myalbum/photos/thumbs/706.jpg]+
-[http://datsun1200.com/modules/myalbum/photo.php?lid=1114 http://datsun1200.com/modules/myalbum/photos/thumbs/1114.jpg]+
- +
-=== linkage ===+
-[http://datsun1200.com/modules/myalbum/photo.php?lid=1113 http://datsun1200.com/modules/myalbum/photos/thumbs/1113.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=1115 http://datsun1200.com/modules/myalbum/photos/thumbs/1115.jpg]+
- +
-discussion: [http://datsun1200.com/modules/newbb/viewtopic.php?topic_id=7127&forum=1#14672 Throttle linkages] +
- +
-wheel and lever linkage+
== Dellorto DHLA == == Dellorto DHLA ==
-Twin Dellorto sidedraughts were used on the [[Datsun_1200_SSS]]+Twin Dellorto sidedraughts were used on the [[Datsun_1200_SSS]].
 + See main article: [[Dellorto]]
You can identify the venturi side by looking down into the carburetor for the ID marks. You can identify the venturi side by looking down into the carburetor for the ID marks.
-[http://datsun1200.com/modules/myalbum/photo.php?lid=872 http://datsun1200.com/modules/myalbum/photos/thumbs/872.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=195 http://datsun1200.com/modules/myalbum/photos/thumbs/195.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=263 http://datsun1200.com/modules/myalbum/photos/thumbs/263.jpg]+[http://datsun1200.com/modules/myalbum/photo.php?lid=872 http://datsun1200.com/uploads/thumbs/872.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=195 http://datsun1200.com/uploads/thumbs/195.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=263 http://datsun1200.com/uploads/thumbs/263.jpg]
[http://www.powerpage.dk/just_karb/dellorto.htm Justering af Dellorto] [http://www.powerpage.dk/just_karb/dellorto.htm Justering af Dellorto]
Line 156: Line 156:
=== Motorcyle Carbs === === Motorcyle Carbs ===
 + See main article: [[Bike Carbs]]
-See main article: [[Bike Carbs]]+http://datsun1200.com/uploads/thumbs/961.jpg
- +
-http://datsun1200.com/modules/myalbum/photos/thumbs/961.jpg+
= Air filters = = Air filters =
Line 166: Line 165:
See main article: [[Cold Air Intake]] See main article: [[Cold Air Intake]]
-[http://datsun1200.com/modules/myalbum/photo.php?lid=1133 http://datsun1200.com/modules/myalbum/photos/thumbs/1133.jpg]+[http://datsun1200.com/modules/myalbum/photo.php?lid=1133 http://datsun1200.com/uploads/thumbs/1133.jpg]
= Suppliers = = Suppliers =
Line 172: Line 171:
[http://www.redlineweber.com/html/Types/making_the_right_choice.htm Redline Weber North America: Making the Right Weber Choice] [http://www.redlineweber.com/html/Types/making_the_right_choice.htm Redline Weber North America: Making the Right Weber Choice]
-<ul><li>[http://www.redlineweber.com/html/Types/making_the_right_choice.htm Redline Weber North America] - Weber 32/36 DGV & DCOE carbs, adapters, and intake manifolds</a><ul><li>A-series 40 DCOE kit: K 625+ [http://www.redlineweber.com/html/Types/making_the_right_choice.htm Redline Weber North America] - Weber 32/36 DGV & DCOE carbs, adapters, and intake manifolds
-<li>A-series Cannon single DCOE intake: 99003.821+ A-series 40 DCOE kit: K 625
-<li>A-series DGAV performance kit: K 624+ A-series Cannon single DCOE intake: 99003.821
-<li>A-series California smog-legal DGAV kit: K 8625+ A-series DGAV performance kit: K 624
-<li>linkage, manifolds, adapters, air filters, gaskets available</ul><li>[http://www.cyberauto.com/index.php/sheet017.htm Cyberspace Auto] - Sells Redline Weber kits. Complete DCOE kit for A-series $514.+ A-series California smog-legal DGAV kit: K 8625
-<li>[http://www.racetep.com/weberX.html Racetep] sells Redline Weber kits. Complete kit for A-series DGEV 32/36: $376.95 USD.+ linkage, manifolds, adapters, air filters, gaskets available
 + 
 +[http://www.cyberauto.com/index.php/sheet017.htm Cyberspace Auto] - Sells Redline Weber kits. Complete DCOE kit for A-series $514.
 + 
 +[http://www.racetep.com/weberX.html Racetep] sells Redline Weber kits. Complete kit for A-series DGEV 32/36: $376.95 USD.
<br>[http://www.racetep.com/webercarbjet.html jetting] <br>[http://www.racetep.com/webercarbjet.html jetting]
-<li>Remanufactured Carbs by Holley: [http://www.holley.com/Reman/ImpCarb/Nissan.html http://www.holley.com - Nissan] 
-<li>http://www.carburation.com/nisnistruc.html Includes prices 
-<li>See the club's [http://datsun1200.com/modules/newbb/viewforum.php?forum=2 Classifieds] forum. 
-<li>http://www.ebay.com>eBay</ul> 
 +Remanufactured Carbs by Holley: [http://www.holley.com/Reman/ImpCarb/Nissan.html http://www.holley.com - Nissan]
 +
 +http://www.carburation.com/nisnistruc.html Includes prices
 +
 +See the club's [http://datsun1200.com/modules/newbb/viewforum.php?forum=2 Classifieds] forum.
 +
 +http://www.ebay.com
== Intake Manifolds == == Intake Manifolds ==
-<br>suppliers:<ul><li>[http://www.twminduction.com TWM]+ See Main Article: [[Aftermarket intake manifold]]
-<li>[http://www.ramflo.5u.com Lynx] single (PN M041) and dual (PN M042) DCOE/DHLA manifolds, dual SU manifold (M137)+ 
-<li>[http://www.twminduction.com TWM Induction] intakes, carbs, etc+suppliers:
-<li>[http://www.ramflofilters.com>Ramflo] [http://www.lynxcorp.com.au Lynx] manifolds & Kay C (KC) adapter, Ramflo filters and Weber carbs+ 
-<li>Ram intake downdraft manifold +[http://www.ramflo.5u.com Lynx] single (PN M041) and dual (PN M042) DCOE/DHLA manifolds, dual SU manifold (M137)
-<li>Cannon/Canon+
-<li>[http://www.redlineauto.com.au/manifold.html Redline Auto (Australia)] makes single and dual DCOE manifolds and linkage, for A12 through A15 motors.+[http://www.twminduction.com TWM Induction] intakes, carbs, etc
-<li>Same parts are available from [http://www.holleycarbs.com.au/redline_hi_winder.html Holley (Australia)]+ 
-<li>[http://www.swmotorsport.com/ Stewart Wilkins Motorsports] GX manifold - only $260 AUD+[http://www.ramflofilters.com Ramflo] [http://www.lynxcorp.com.au Lynx] manifolds & Kay C (KC) adapter, Ramflo filters and Weber carbs
-<li>[http://www.ebay.com eBay]</ul>+ 
-<p>+Ram intake downdraft manifold
 + 
 +Cannon/Canon
 + 
 +[http://www.redlineauto.com.au/search.aspx?searchterm=Manifold+datsun Redline Auto (Australia)] makes single and dual DCOE manifolds and linkage, for A12 through A15 motors.
 +<br>Same parts are available from [https://www.holleycarbs.com.au/redlineHighWinder.htm Holley (Australia)]
 + 
 +[http://www.swmotorsport.com.au/product_info.php?cPath=5_35&products_id=248 Stewart Wilkins Motorsports] GX manifold - only $260 AUD
 + 
 +http://www.ebay.com
 + 
Aftermarket manifold finish quality can be really poor so check for flat flanges, port overlap. See [http://home.att.net/~jason510/weber.htm Jason's Weber page]. Aftermarket manifold finish quality can be really poor so check for flat flanges, port overlap. See [http://home.att.net/~jason510/weber.htm Jason's Weber page].
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Headers (extractors) are a natural compliment to a bigger carb. Now that your 1200 can breathe better, got to let it exhale better too. Replacing the stock cost iron exhaust manifolds with a tubular headers (extractor), along with a bigger exhaust system will acheive this. An alternative is the Datsun 1200 GX or EGI exhaust manifold, which is cast but similar to headers. Headers (extractors) are a natural compliment to a bigger carb. Now that your 1200 can breathe better, got to let it exhale better too. Replacing the stock cost iron exhaust manifolds with a tubular headers (extractor), along with a bigger exhaust system will acheive this. An alternative is the Datsun 1200 GX or EGI exhaust manifold, which is cast but similar to headers.
-[http://datsun1200.com/modules/myalbum/photo.php?lid=375 http://datsun1200.com/modules/myalbum/photos/thumbs/375.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=376 http://datsun1200.com/modules/myalbum/photos/thumbs/376.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=506 http://datsun1200.com/modules/myalbum/photos/thumbs/506.jpg]+[http://datsun1200.com/modules/myalbum/photo.php?lid=375 http://datsun1200.com/uploads/thumbs/375.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=376 http://datsun1200.com/uploads/thumbs/376.jpg][http://datsun1200.com/modules/myalbum/photo.php?lid=506 http://datsun1200.com/uploads/thumbs/506.jpg]
Bigger pipe lets more volume flow, so is good for bigger engines, or for those A12s that that rev higher (higher flow).<ul><li>4-into-1 headers are good for keeping torque up</li> Bigger pipe lets more volume flow, so is good for bigger engines, or for those A12s that that rev higher (higher flow).<ul><li>4-into-1 headers are good for keeping torque up</li>
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<li>Equal-length (bundle of snakes)</li> <li>Equal-length (bundle of snakes)</li>
<li>"shorty" headers, around the same length as the original manifold are easy to install, but not optimum for HP or torque. I don't know of any commercial version for 1200s, but here's a custom-made one: <li>"shorty" headers, around the same length as the original manifold are easy to install, but not optimum for HP or torque. I don't know of any commercial version for 1200s, but here's a custom-made one:
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=376 http://datsun1200.com/modules/myalbum/photos/thumbs/376.jpg]</li></ul>The stock exhaust system used 1.5 inch tubing. Here are the recommendations:+<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=376 http://datsun1200.com/uploads/thumbs/376.jpg]</li></ul>The stock exhaust system used 1.5 inch tubing. Here are the recommendations:
<blockquote>Stock with Weber 32/36 carb: 1.75 inch exhaust <blockquote>Stock with Weber 32/36 carb: 1.75 inch exhaust
Higher-rev Camshaft (up to 7000 rpm use): 2 inch exhaust Higher-rev Camshaft (up to 7000 rpm use): 2 inch exhaust
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suppliers:<ul> suppliers:<ul>
<li>Nismo <li>Nismo
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=414 http://datsun1200.com/modules/myalbum/photos/thumbs/414.jpg]</li>+<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=414 http://datsun1200.com/uploads/thumbs/414.jpg]</li>
<li>TriMill</li> <li>TriMill</li>
<li>[http://www.south-yokohama.com/ng/dst9128.html South Yokohama] equal length header</li> <li>[http://www.south-yokohama.com/ng/dst9128.html South Yokohama] equal length header</li>
Line 224: Line 240:
<li>[http://www.swmotorsport.com/ Stewart Wilkins Motorspors] Extractors $177 and $277</li> <li>[http://www.swmotorsport.com/ Stewart Wilkins Motorspors] Extractors $177 and $277</li>
<li>Hurricane</li> <li>Hurricane</li>
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=799 http://datsun1200.com/modules/myalbum/photos/thumbs/799.jpg]</li>+<li>[http://datsun1200.com/modules/myalbum/photo.php?lid=799 http://datsun1200.com/uploads/thumbs/799.jpg]</li>
</ul>New Zealand<ul> </ul>New Zealand<ul>
<li>Coby Manufacturing in Hamilton, NZ make 2 sets of different extractors to fit the A series motors</li> <li>Coby Manufacturing in Hamilton, NZ make 2 sets of different extractors to fit the A series motors</li>
-<br>Euclid Ave, Hamilton Phone: 0-7-849 1765</li>+<li>Euclid Ave, Hamilton Phone: 0-7-849 1765</li>
<li>[http://www.autopia.co.nz Autopia] in Christchurch</li> <li>[http://www.autopia.co.nz Autopia] in Christchurch</li>
</ul> </ul>
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== A/F Meters == == A/F Meters ==
Air/Fuel ratio meters use a Lambda sensor (oxygen sensor) to tell you if the carb if running rich or lean. Air/Fuel ratio meters use a Lambda sensor (oxygen sensor) to tell you if the carb if running rich or lean.
-* [http://zcarmag.com/tech_info Zcar Magazine] two excellent articles on using Lambda sensor. 
-* [http://home.att.net/~jason510/weber.htm Jason's Weber page] 
 + See main article: [[Oxygen_Sensor#Air_Fuel_Ratio_Sensor|Oxygen Sensor Gauge]]
[[Category:Fuel System]] [[Category:Fuel System]]

Current revision

Which Carburetor should I use?

Also see: 
Weber 32/36 Carburetor
Parts Reference

Contents

Which is better? Sidedraft or downdraft?

In a way, downdraft is very good and inexpensive -- all A-series engine come with a carburetor, so it's all ready to go.

With most inline engines sidedrafts are better because the air/fuel mixture goes more straightly into the cylinder. The air-fuel mixture doesn't have to go down the carb, then make a 90 degree turn in the manifold to get into the cylinder. This helps the airflow, but more importantly fuel doesn't turn as fast as the air, which can cause mixture distribution problems when the path isn't straight. But on a V8s or flat engines with the engine at an angle, the downdraught might have the advantage of a straighter path (this is why all-out V8s and Porsche engines often use Weber downdrafts).

Additionally, with twin dual-throttle sidedrafts on an inline four cylinder, you get the extra advantage of a tuned-port intake path for each intake port. This is just like the individual tuned-port runners used in fuel injection, which is good for low-speed torque, and good for high-end power. Though few if any sidedraft manifolds use long runners, but are instead designed for higher rpm (short runners), the individual throttles give good low speed torque.

discussion: Downdraught? Sidedraught

Consider Fuel Injection

Think about Fuel Injection, which can use the sidedraft carburetor manifold or factory Datsun parts. It's easier than most think. By removing the venturi required by a carburetor, maximum airflow and thus maximum horsepower can be obtained. See the main article Fuel Injection.

830.jpg1048.jpg44.jpg

Single or Twin?

Which is better a single carb setup, or a twin-carb kit?

  • Definitely the twin two-barrel gives best performance for a 4-cylinder engine. Twin Weber/Dellorto/Mikuni = 4 throttles.
  • From a cost standpoint, single carburetors are better -- about half the cost
  • For reliability consideration, single carburetor is superior. Most of the performance without the hassle

Contrary to what you might think, twin carbs don't give twice the airflow of single carbs -- because the twins are feeding one or two cylinders, they are only being used half the time.

With twin dual-throttle sidedrafts on an inline four cylinder, you get the extra advantage of a tuned-port intake path for each intake port. This is just like the individual tuned-port runners used in fuel injection, which is good for low-speed torque, and good for high-end power. Though few if any sidedraft manifolds use long runners, but are instead designed for higher rpm (short runners), the individual throttles still give good low speed torque.

Downdrafts

The Downdraught carburetors used on A-series engine are nearly always one of these:

  • Hitachi DCG306/DCH306: This is the stock carburetor for Datsun A-series engines, and was also used by Honda and other auto makers
  • Weber 32/36 Carburetor (DGV) a progressive secondary throttle design. It is a bit large for A-series engines but will pick up the HP above 5,000 RPM.
  • Weber 38/38 DGAS (synchronous throttle, i.e. both throats open at the same time). This is too large for most A-series, but can work well on heavily modified A14/A15

Of course downdraft carbs of other brands can be used, but these are the popular ones.

Stock Hitachi 306

The stock Datsun 1200 carburetor has the:

  • best fuel economy
  • best driveability e.g. smoothness of throttle response

Although properly jetted and synchronized Webers can be made to run just as well, they will take some special tuning effort to equal this.

See the main article Carburetor Overview.

1008.jpg42.jpg467.JPG

Weber DGV 32/36

The Weber DGV series downdraft carb is an excellent choice for the daily driver stock or lightly modified A-series engine. See the main article Weber 32/36 Carburetor.

Note that the Holley G180 and Holley 5200 are the same carburetor, as commonly found on Ford engines and others. These are made by Holley with a license from Weber of Italy.
  • Least expensive upgrade choice
  • can use stock A-series engine manifold by using a simple adapter plate
  • Uses the Solex two-barrel bolt pattern

90.jpg591.jpg798.jpg799.jpg881.jpg

Weber IDF

Downdraft carbs of exotic car fame

174_5c1d3d3b8f310.jpgPost 490218 7256.jpgAlbum 7256

IDF44s on F.E.T. manifold (POST more pics)
174_5c1d3d288463c.jpgPost 490218 174_5c1d3d49bb73e.jpgPost 490218 174_5c1d3d6f893c5.jpgPost 490218

IDFs on A12GX manifold
16020.jpgAlbum 16020 16018.jpgAlbum 16018 16019.jpgAlbum 16019

Sidedrafts

Sidedraught carburetors are more performance-oriented as they feed the engine ports is a straighter line. But they are generally more expensive and require a special intake manifold. By contrast, a traditional downdraft caburetor will fit your existing manifold.

There are two basic kinds of sidedraughts:

  • Constant Vacuum: SU, Hitachi and Stromberg types
  • jetted carbs: Weber DCOE, Mikuni/Solex PHH and Dellorto DHLA


The constant vacuum carburetors all fit the same manifold

  • Hitachi (SU-style): stock GX carburetors
  • SU carbs - made in England (not used by factory Datsuns)


These conventional sidedraft carburetors are all use the same intake manifold (same bolt pattern):


LHD Considerations

NOTE: Dual sidedrafts of the Weber/Mikuni-Solex/Dellorto type hit the brake master cylinder on LHD 1200s. Hitachi Twin Carb fits better, or you can use various means to make them fit.

See main article: LHD Sidedrafts

HJE38W Hitachi Twin Sidedrafts (GX engine carbs)

These variable-venturi carbs are the factory setup for Datsun 1200 GX cars (twin SU-type Hitachis). Not sure if these are swappable with the SUs and Solex/Zenith-Stromberg carbs, but are of similar design. These were also fitted to the Bluebird 411 SS and SSS, 240Z/260Z, B110GX, B210GX, PE10, 180B SSS, P510 SSS, and 311 roadsters.

Available in "dome-top" through 1972 and then "flat-top" versions in 1973 and up. Most use the 38 (38mm bore), but there are 46s on the 2000cc Roadster.
  • Angled runner design is generally a plus, although the a-series heads don't have angled runners to match
  • continuously variable venturi design (slides)
  • single throttle is a minus, compared to the dual Weber DCOEs (four throttles total)
776.jpg1002.jpg1003.jpg616.jpg1132.jpg

The Hitachis are tuned in a manner similar to SU carburetors. Here are links to tuning information:

229.jpg619.jpg955.jpg960.jpg

Mikuni PHH

Mikuni bought the Solex PHH license in the early 1970s and thoroughly redesigned it since then. The only parts in common between these two carbs are the diaphragm accelerator pump arrangement. The Mikuni now resembles a cross between a Weber DCOE and a Solex. They are the "set and forget" sidedrafts. Their flow rates aren't quite as high as the Webers, which is why they're not favored by racers, and jet availability is not as good. (Mikuni North America is the primary jet supplier).
Reference: bimmers.com

See main article: Mikuni PHH

152.jpg787.jpg377.jpg381.jpg

Nissan Competition used to sell Mikuni jet parts.

Weber DCOE

See main article: Weber DCOE carburetor

The great thing about these carbs (as well the Dellorto DHLA) is that the jets are externally accessible, even when the air filter is on. This makes jet changes at the racetrack a snap.

These are available in 40, 42, 45, 48, 50, and 55mm sizes. Most Datsun A-series street engines run the dual 40s. Note that there are different size venturis for the 40s. This "barrel" size (40 or 45) doesn't determine the airflow, which is determined by the size of the main venturi (choke). The 28mm venturi might work best for a street A12, while a 38 venturi would be good for an 8,000 rpm A14.

Single carb
album

album

Dual DCOE
album

Dellorto DHLA

Twin Dellorto sidedraughts were used on the Datsun_1200_SSS.

See main article: Dellorto

You can identify the venturi side by looking down into the carburetor for the ID marks.

872.jpg 195.jpg 263.jpg

Justering af Dellorto

Other Variable Venturi Carbs

These "slide venturi" carbs have the advantage of at full throttle, there is minimal restriction to airflow compared to a traditional fixed-venturi carburetor. Vacuum and airflow regulate the venturi movement, and excellent fuel metering is achieved with tapered rods that move with the venturi, allowing more or less air to flow.

  • Mikuni motorcycle carbs
  • SU - all types
  • Solex/Zenith-Stromberg
  • Hitachi sidedrafts e.g. GX, A12T, A14T and Blubird SSS

Motorcyle Carbs

See main article: Bike Carbs

961.jpg

Air filters

Cold air is very important. Instead of hot underhood air, bring in cooler fresh air from outside. It makes a big difference, and is a nearly free -- no "intercooler" needed.

See main article: Cold Air Intake

1133.jpg

Suppliers

Carburettor

Redline Weber North America: Making the Right Weber Choice

Redline Weber North America - Weber 32/36 DGV & DCOE carbs, adapters, and intake manifolds
A-series 40 DCOE kit: K 625
A-series Cannon single DCOE intake: 99003.821
A-series DGAV performance kit: K 624
A-series California smog-legal DGAV kit: K 8625
linkage, manifolds, adapters, air filters, gaskets available

Cyberspace Auto - Sells Redline Weber kits. Complete DCOE kit for A-series $514.

Racetep sells Redline Weber kits. Complete kit for A-series DGEV 32/36: $376.95 USD.
jetting

Remanufactured Carbs by Holley: http://www.holley.com - Nissan

http://www.carburation.com/nisnistruc.html Includes prices

See the club's Classifieds forum.

http://www.ebay.com

Intake Manifolds

See Main Article: Aftermarket intake manifold

suppliers:

Lynx single (PN M041) and dual (PN M042) DCOE/DHLA manifolds, dual SU manifold (M137)

TWM Induction intakes, carbs, etc

Ramflo Lynx manifolds & Kay C (KC) adapter, Ramflo filters and Weber carbs

Ram intake downdraft manifold

Cannon/Canon

Redline Auto (Australia) makes single and dual DCOE manifolds and linkage, for A12 through A15 motors.
Same parts are available from Holley (Australia)

Stewart Wilkins Motorsports GX manifold - only $260 AUD

http://www.ebay.com

Aftermarket manifold finish quality can be really poor so check for flat flanges, port overlap. See Jason's Weber page.

Exhaust System

Headers (extractors) are a natural compliment to a bigger carb. Now that your 1200 can breathe better, got to let it exhale better too. Replacing the stock cost iron exhaust manifolds with a tubular headers (extractor), along with a bigger exhaust system will acheive this. An alternative is the Datsun 1200 GX or EGI exhaust manifold, which is cast but similar to headers.

375.jpg376.jpg506.jpg

Bigger pipe lets more volume flow, so is good for bigger engines, or for those A12s that that rev higher (higher flow).
  • 4-into-1 headers are good for keeping torque up
  • Tri-Y. These are dual 2-into-1, then going into one again
  • Equal-length (bundle of snakes)
  • "shorty" headers, around the same length as the original manifold are easy to install, but not optimum for HP or torque. I don't know of any commercial version for 1200s, but here's a custom-made one:
    376.jpg
The stock exhaust system used 1.5 inch tubing. Here are the recommendations:
Stock with Weber 32/36 carb: 1.75 inch exhaust Higher-rev Camshaft (up to 7000 rpm use): 2 inch exhaust Racing engine (10,000 rpm): 2.5 inch exhaust

Exhaust System Suppliers

You can make your own exhaust system. If you know how to weld, You can make your one out of some steel tubing and a bit of 10mm plate for the flange.

suppliers:AUSTRALIANew Zealand
  • Coby Manufacturing in Hamilton, NZ make 2 sets of different extractors to fit the A series motors
  • Euclid Ave, Hamilton Phone: 0-7-849 1765
  • Autopia in Christchurch

Tuning -- Making your Carb run right for YOUR engine

NOTE: For in-depth info on carb tuning and performance, buy or borrow a book the type of carb you have. Try your local library or http://www.amazon.com.

If you are getting poor fuel economy, unacceptable low speed bog (hesitation) when accelerating suddenly, overly loud induction noise, or the carbs getting hot enough to boil over fuel, the carbs need tuning or proper installation fitting. See Jason's Weber page


For a general tuning guide to Webers, see:


For Carb-specific tuning data, see:


A/F Meters

Air/Fuel ratio meters use a Lambda sensor (oxygen sensor) to tell you if the carb if running rich or lean.

See main article: Oxygen Sensor Gauge