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| 1962 valiant ( s ) 225 carb probs https://slantsix.org/forum/viewtopic.php?t=41519 |
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| Author: | martin-uk [ Thu Aug 19, 2010 1:50 pm ] |
| Post subject: | 1962 valiant ( s ) 225 carb probs |
it has a clifford manifold with a 4412 carb, but iam only getting 12mgp, it is runing very well , is this to big for this stock motor, if so what would make a good carb forr a bit fuel economy, thanks |
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| Author: | Josh P [ Thu Aug 19, 2010 3:21 pm ] |
| Post subject: | |
I believe the stock intake with the 1bbl carb got 18(ish) mpg, so you really aren't doing too much worse. However, regarding the "too much carb" question... if you talking about the Holley 4412, its a 500 cfm carb, and I believe its a bit much for a stock engine. But others will be able to provide better info. Also, I've heard the Clifford intakes are also excessively large for a stock engine. |
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| Author: | martin-uk [ Thu Aug 19, 2010 10:33 pm ] |
| Post subject: | |
what would be a better choice for the stock motor |
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| Author: | wjajr [ Fri Aug 20, 2010 4:28 am ] |
| Post subject: | |
Martin, welcome aboard. When you get a chance tell us about your car, and perhaps post a photo of it for all to enjoy. To help make your stewardship of your Valiant easer we strongly suggest acquiring a copy of a “Factory Manual†that covers all aspects of your car. These manuals can be found on the net from various venders in book & digital form. Now, on to your question: [quote]what would be a better choice for the stock motor[/quote] A “Super Six†stock factory setup from a later model car, and a larger exhaust system would work real well. It is a two barrel carburetor on a factory two barrel intake allowing the stock manifold heat to be used. If you use “Search†one can find many discussions covering the application of a Super Six conversion. A 500 cfm carburetor is way too big for a stock engine, as a stock slant just doesn’t move enough air to make it opperete efficiently. And, that Clifford intake will want to be paired with headers, or Dutra Duel exhaust manifolds which will require some kind of manifold heating contraption if you are going to use the car as an every day driver as unheated manifolds don’t work well in cooler climates. Additional reading of interest can be found on the “Articles†page. Bill |
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| Author: | Josh P [ Fri Aug 20, 2010 9:59 am ] |
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Hey Martin, can you tell us a bit more about your car? Does it have headers or stock-style exhaust manifold? Does it stumble or lag at low RPM (especially when you floor the gas pedal)? Are you sure it is a stock engine, maybe a previous owner did something? Since you've said it runs well with your current setup, it sounds unlikely that you have a stock engine. In the Slant Six Carb Article, there is brief mention of a Holley 350 (or maybe 500) CFM 2bbl on a stock engine as an unsuccessful experiment. I only see four options: A) The engine doesn't run as well as you thought (maybe you haven't gotten to drive it much, or not under heavy throttle?). B) The engine is not actually stock and has had some work down. C) Both A and B (some work was done, but its probably still better to go with a smaller carb) Goodluck! |
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| Author: | martin-uk [ Sat Aug 21, 2010 2:54 pm ] |
| Post subject: | |
hi, well iam a engineer for volvo GB TRUCKS ,i have been with them for 14 years ,at first as an workshop technician ,, supervisor then to a volvo training manager, to now i run the bodyshop,won 2 volvo technican world champion ships . i have my own workshop at home, i have restored ferraris and cobra , rebuilt all engines, have my own large late etc, designed and built a new style ac cobra chassis for a 2+2 corba.so i'm very technically able, back to the car, this clifford was on the car when i bought it 3 months ago, it has been in the uk since 2003 , came from oz, just having the interior redone this week, i have remove the axle and stripped and rebuilt, same with the 904 trans, not touched engine apart from alternator conversion to internaly regulated, and made new full wiring loom,restored the dash and bezel, renew the steering idler arm, drop arm and all the ball joints and track rod ends, yes its a daily to work, and yes it goes fine does not bog down or miss or smoke,[/url] |
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| Author: | martin-uk [ Sat Aug 21, 2010 3:03 pm ] |
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http://s744.photobucket.com/albums/xx89 ... ysler2.jpg http://i744.photobucket.com/albums/xx89 ... rsmall.jpg should be my car. but these are photos when i got the car, i will have to post new ones, thanks |
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| Author: | martin-uk [ Wed Aug 25, 2010 10:37 pm ] |
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so that was a big help,thanks |
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| Author: | Josh P [ Thu Aug 26, 2010 12:24 am ] |
| Post subject: | |
Hmm looks like you didn't get the answer you wanted... hope this helps a bit more. A better carb choice would be the 2bbl Carter BBD. I believe it flows around 280 CFM and its a great choice, giving pretty good fuel economy and a noticeable jump in performance over the stock 1bbl carbs. However, the BBD doesn't bolt to your Clifford intake (not even with the 2bbl adaptor) and you will need to have an adaptor fabricated. Also, I think you'd have a tricky time with the throttle linkage. There is also a 2bbl Holley 2280 that was a later alternative. I believe it flow a little less (around 250 CFM) and has sequential opening venturis. However, AFAIK this also does not bolt to your intake. You can find super six 2bbl intakes in junkyards or on ebay, or I believe the Offy intake will work just fine, and looks like it would give you less throttle linkage issues. |
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| Author: | martin-uk [ Thu Aug 26, 2010 12:35 pm ] |
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hi thanks, i have a 4412 on it at the moment which is a 2bbl holley . |
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| Author: | Josh P [ Sun Aug 29, 2010 5:40 pm ] |
| Post subject: | |
Hey martin, Yes, I realize that the Holley 4412 is a 2bbl, however it also is ment for an engine that enjoy a flow of 500 CFM. Which, I believe, is considered a bit much for a stock slant six. I believe that it is said, in the carb article linked above, that a Carter BBD 2bbl (280 CFM) is as big a carb as you want to put on a stock motor. Since you say your engine runs fine, I am led to believe that you have a non-stock engine. |
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| Author: | Charrlie_S [ Mon Aug 30, 2010 4:26 am ] |
| Post subject: | |
Martin. Do this very carefully, Remove the air cleaner, start the engine, and look down the carb throat, with the engine running (do not put your head directly over the carb). Bring the rpm up slowly, and see if fuel starts coming out of the pump shooters, as the rpm gets up to around 2,000 rpm. I'm not talking about the normal pump shot, but like fuel is being drawn out. I have seen several 4412 carbs do this, and it will effect the fuel milage. I have a 4412 on my Cuda that does this, and have been unable to correct the problem. I have talked to Holley tech, without any help. My personal opinion is a small 4bbl would be better then a large 2bbl. As the primary barrels of the 4bbl are smaller, and should give better drivability and fuel milage, untill you stand on the throttle, and open the secondarys. Also as others have said, the Offie manifold is a better street manifold then the Clifford, but try working with what you have. PS: the 4412 carb is rated at 500 cfm at a pressure drop of 3 inches, and 4 bbl carbs are rated at a pressure drop of 1.5 inches. so a 500 holley 2 bbl is not the same as a 500 holley 4 bbl. A 500 2 bbl only flow about 353 cfm when rated at the 4bbl pressure drop. |
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