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Pics of carb conversion
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aeronca65t
Great Pumpkin
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Your images need to be stored on another site and "linked" here.
(this is a pretty common arrangement on forums).
If you do not already have your images stored somewhere, I'd suggest you upload your images to Photobucket or Flickr (Both free. You can find them using Google).
The info below is from the "FAQ" part of British car Forum. Once you have images stored on your personal site or web page, use these instructions..........
In order to add an image to your message or your signature, you must have the image already available on a web server and reachable by a URL. This can be an image on your own personal web page, for example. To place an image within a message, simply use the following Markup Tag:
[ image]https://www.url_to_image.com/image_name.gif[/image]
For example, if you have an image called cateye.gif and its available from your own website at https://www.mywebsite.com/pics, then you would use the following image markup:
[ image]https://www.mywebsite.com/pics/cateye.gif[/image]
You can do the same for your signature. Click the My Home option found on any page. Then, under the Main Configuration heading, click on "Personal Information, email, password...". Look for the Signature box, and enter your desired information, including any images/markup as above.
Note: To keep the forums loading quickly for everyone, it is recommended that you do not exceed 35k for your image size.
Also note: There is an extra space between the "[" and "image" in the example above. Do not add this space when you add your actual pictures.
(this is a pretty common arrangement on forums).
If you do not already have your images stored somewhere, I'd suggest you upload your images to Photobucket or Flickr (Both free. You can find them using Google).
The info below is from the "FAQ" part of British car Forum. Once you have images stored on your personal site or web page, use these instructions..........
In order to add an image to your message or your signature, you must have the image already available on a web server and reachable by a URL. This can be an image on your own personal web page, for example. To place an image within a message, simply use the following Markup Tag:
[ image]https://www.url_to_image.com/image_name.gif[/image]
For example, if you have an image called cateye.gif and its available from your own website at https://www.mywebsite.com/pics, then you would use the following image markup:
[ image]https://www.mywebsite.com/pics/cateye.gif[/image]
You can do the same for your signature. Click the My Home option found on any page. Then, under the Main Configuration heading, click on "Personal Information, email, password...". Look for the Signature box, and enter your desired information, including any images/markup as above.
Note: To keep the forums loading quickly for everyone, it is recommended that you do not exceed 35k for your image size.
Also note: There is an extra space between the "[" and "image" in the example above. Do not add this space when you add your actual pictures.
Easiest for me to give a link to here,
https://www.mgexperience.net/phorum/read.php?3,1044445
https://www.mgexperience.net/phorum/read.php?3,1044445
dklawson
Yoda
Offline
Mark, this is a cross-marque question and a cross-carb question as well but I hope others will indulge me.
Your engine is the 1500cc version of my Spitfire project. I am not wild about the ZS carb either and I purchased an HS4 carb to replace it. What needle and jet did you install in the HIF carb? Your engine is 200cc bigger, and I know the HIF will be different, but I should be able to use a site like that hosted by Paul Tegler to find the comparable needle and jet for the HS4. This would at least give me a starting point. Thanks.
Your engine is the 1500cc version of my Spitfire project. I am not wild about the ZS carb either and I purchased an HS4 carb to replace it. What needle and jet did you install in the HIF carb? Your engine is 200cc bigger, and I know the HIF will be different, but I should be able to use a site like that hosted by Paul Tegler to find the comparable needle and jet for the HS4. This would at least give me a starting point. Thanks.
blkcorvair
Jedi Knight
Offline
Doug, I had the HS4 on my 1500 til last week when I upgraded to a Hitachi Style HS6. But the nice thing about having a single carb is that there is only one needle you messing with. So set your idle with the one that's in there. If it came off a dual carb application than its likely its going to lean out on anything above this. Mark the needle position at idle and than put the needle in a drill press and shave it with a few mild pieces of Sand Paper. If you've got a air / Fuel gauge this is a real nice way to tune. I was able to dial my HS4 in perfectly threw all the ranges. Still working with the larger carb now. Its been a bit trickier.
I didn't need to change the needle and am guessing it was the original. I used John Twist's video information to tune it. You're going to be surprized as to how much power you get out of the carb!
Doug, the HIF is a newer carb that had the float within the body of the carb rather than mounted to the side of the carb. Both should work the same. I've read that some carb floats sit at an angle which you do not want. A little modification to the float and you can have it set verticle.
Thanks again Scott.
Doug, the HIF is a newer carb that had the float within the body of the carb rather than mounted to the side of the carb. Both should work the same. I've read that some carb floats sit at an angle which you do not want. A little modification to the float and you can have it set verticle.
Thanks again Scott.
blkcorvair
Jedi Knight
Offline
You need not modify the float. (instead the Float bowl angle may need to be changed.) There is a rubber piece between the Carb and the Float bowl. This piece is available in different degrees to change the relative angle when mounted on the intake manifold. I belive Hap has them and perhaps Mini Mania.
aeronca65t
Great Pumpkin
Offline
Another thought on this.......
On older HS4 carbs (not HIF) , the float chamber may not "sit level" if the carb was designed to fit an angled manifold (like a Volvo).
Look at the picture below and find bolt # 36. That bolt goes through the carb body and screws into the float chamber (#28). There is a notch cast into #28 that indexes into #23 and #24 to locate the bowl at the proper angle. In a non-angled manifold (like a 1500 Midget), the chamber may end up looking "tipped over". I just ground off the cast notch and tightened the float chamber while at the correct angle. It never shifted from that angle in three years.
On older HS4 carbs (not HIF) , the float chamber may not "sit level" if the carb was designed to fit an angled manifold (like a Volvo).
Look at the picture below and find bolt # 36. That bolt goes through the carb body and screws into the float chamber (#28). There is a notch cast into #28 that indexes into #23 and #24 to locate the bowl at the proper angle. In a non-angled manifold (like a 1500 Midget), the chamber may end up looking "tipped over". I just ground off the cast notch and tightened the float chamber while at the correct angle. It never shifted from that angle in three years.
blkcorvair
Jedi Knight
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the part that can be changed in the pic to adjust the angle is #23. But yes Nial I never thought of doing it that way.
dklawson
Yoda
Offline
Mark, I'm familiar with the HIF being the later integrated float design, what I was hoping for was that you could tell me what needle you're using and what jet size is in your HIF. I can cross those over to the comparable parts as used on the earlier HS4 carb and use that as a starting point for tuning.
The single HS4 carb I have is not part of a pair but was removed from a 998cc Mini and I have some additional needles for it. According to the SU tuning book, the additional needles appear to have been used on the 1300 Triumph engines fitted in Europe (to the Toledo) and to the 1275 A-series fitted to some Austin Americas. I may be close enough with those two needles to have a good initial setup. I was just curious to see how close your setup with the HIF on a 1500 would be to what I have available.
As Scott said, I will need to swap the rubber bushing for the HS carb's float bowl so it is more or less vertical. The Mini mounted this at a bit of an angle that will be unsuitable.
The single HS4 carb I have is not part of a pair but was removed from a 998cc Mini and I have some additional needles for it. According to the SU tuning book, the additional needles appear to have been used on the 1300 Triumph engines fitted in Europe (to the Toledo) and to the 1275 A-series fitted to some Austin Americas. I may be close enough with those two needles to have a good initial setup. I was just curious to see how close your setup with the HIF on a 1500 would be to what I have available.
As Scott said, I will need to swap the rubber bushing for the HS carb's float bowl so it is more or less vertical. The Mini mounted this at a bit of an angle that will be unsuitable.
Doug,
Fortunately I didn’t need to get into needle sizes since the carb adjusted well as is. Unfortunately for you I do not know what size is in the carb. Here are some web pages that may help you out. I only assume that the spring that is in my carb is red, however I found no indication on the spring itself.
https://www.mgexperience.net/archive/ot_opinions_on_su_carb_plan/536468
https://bhive.tierranet.com/100MGBhif4carburetor.htm
My needle assembly looks like this:
https://bhive.tierranet.com/images/101-205.jpg
Here is a chart of SU carbs. Mine came off an MGB and it is a HIF4 I assume it to be one of the stock models:
https://www.teglerizer.com/mgstuff/SUcarbs.htm
Fortunately I didn’t need to get into needle sizes since the carb adjusted well as is. Unfortunately for you I do not know what size is in the carb. Here are some web pages that may help you out. I only assume that the spring that is in my carb is red, however I found no indication on the spring itself.
https://www.mgexperience.net/archive/ot_opinions_on_su_carb_plan/536468
https://bhive.tierranet.com/100MGBhif4carburetor.htm
My needle assembly looks like this:
https://bhive.tierranet.com/images/101-205.jpg
Here is a chart of SU carbs. Mine came off an MGB and it is a HIF4 I assume it to be one of the stock models:
https://www.teglerizer.com/mgstuff/SUcarbs.htm