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MGB HIF44 carb

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Vegasmgdriver

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Morning all, another fantastic morning in Southern Nevada... They're calling for 112 by noon, "but it's a DRY HEAT!":cool-new:

Has anyone replaced their SU 175 Carb. On a 79 B with the SU HIF44 that VictoriaBritish sells?

If so, what K&N filter did you use... I can't find any reference in either their catalog or on-line.

i can see it in MOSS's catalog, but I have a 10% off coupon for VB soooo...

"Keep the greasy side down"

Chuck
 
In most cases a change over to HIFs is done by changing the manifold and using two SU carbs. Never heard of just pulling the single carb on the late model MGBs and replacing it with one HIF! There are other modifications that come into the picture if a carb change is done on a late model. If money is not an issue, then go for it, but make sure you know Brit engines before hand. PJ
 
Sounds like frying pan to fire, to me. MUCH better solution would be to find the earlier (pre-'68) manifolds and SU carbs as induction/exhaust. But I suppose that would also mean a cam change and other engine mods to get back to a decent HP output. I'd even choose a Weber 32 DGV downdraught on a Cannon manifold and some exhaust header over the HIF series SU.

BY "SU175" do you mean Zenith Stromberg 175?

What's the goal here, Chuck? More output or more reliability?


And my bad for not welcoming you to the forum!! WELCOME!!
 
DrEntropy said:
Sounds like frying pan to fire, to me. MUCH better solution would be to find the earlier (pre-'68) manifolds and SU carbs as induction/exhaust. But I suppose that would also mean a cam change and other engine mods to get back to a decent HP output. I'd even choose a Weber 32 DGV downdraught on a Cannon manifold and some exhaust header over the HIF series SU.

BY "SU175" do you mean Zenith Stromberg 175?

What's the goal here, Chuck? More output or more reliability?


And my bad for not welcoming you to the forum!! WELCOME!!
Click to expand...

I agree Doc! Even though I'm not a promoter of the Weber 32 DGV, it would be a better change over than one HIF! And I also agree with the cam change. To me if the engine is to remain in the car, to rebuild the Stromberg and get on with it. Sure be a lot cheaper and faster. The Zenith Stromberg isn't a bad carb if properly maintained, actually I think their less trouble than a 32 DGV which has a built in hesitation problem. One I had did anyway. PJ
 
I ran a single HIF6 on the stock combo MGB manifold for about six years on my 1978 MGB.

Sourced the carb from an Austin Marina. I ran a BBQ needle in it.

Performance was better than that of the ZS175 and a whole lot easier to make adjustments.

The combo manifold is the limiting factor.
 
Thanks guys for the advise and the welcome too. Right now, I'm running the original single Zenith Stromberg 175 that's just worn out! I was thinking, rather than trying to repair/rebuild the Zenith, I would order a new SU HIF44. Which VB said was a direct replacement.

I'm not interested in going crazy with the mod, I just want my B to run as well as possible. No changing manifolds or anything else.

BTW Paul I like your "SUPPORT OUR TROOPS" icon, I've spent the last 48 years in or with the USAF... first 20 as an enlisted, then next 28 as a DOD contractor.
 
If you are not inclined to DIY, consider shipping it to Joe Curto. It'll come back better-than new. Bolt it up and press on.

https://joecurto.com/


...and double welcome: Former USAF combat camera weenie here. :thumbsup:
 
Vegasmgdriver said:
Thanks guys for the advise and the welcome too. Right now, I'm running the original single Zenith Stromberg 175 that's just worn out! I was thinking, rather than trying to repair/rebuild the Zenith, I would order a new SU HIF44. Which VB said was a direct replacement.

I'm not interested in going crazy with the mod, I just want my B to run as well as possible. No changing manifolds or anything else.

BTW Paul I like your "SUPPORT OUR TROOPS" icon, I've spent the last 48 years in or with the USAF... first 20 as an enlisted, then next 28 as a DOD contractor.
Click to expand...

Just realized you are running a Zenith Stromberg - I would bury it in the backyard. If it is anything like my Midget, I could never get it right. I vote go for the SU - or even a Weber.
 
Welcome to the excitement! :eagerness:
I tried to rebuild my ZS. It did not work out well. I got it all back together and could never get it tuned again.
 
Vegasmgdriver said:
Thanks guys for the advise and the welcome too. Right now, I'm running the original single Zenith Stromberg 175 that's just worn out! I was thinking, rather than trying to repair/rebuild the Zenith, I would order a new SU HIF44. Which VB said was a direct replacement.

I'm not interested in going crazy with the mod, I just want my B to run as well as possible. No changing manifolds or anything else.

BTW Paul I like your "SUPPORT OUR TROOPS" icon, I've spent the last 48 years in or with the USAF... first 20 as an enlisted, then next 28 as a DOD contractor.
Click to expand...

Thanks, I support all our troops, past, present and future. Their my kinda people! If I say more, I'll be getting too political. Thanks for the comment, your only the fourth person who ever acknowledged it and liked it. One wasn't even a citizen of this country! There I go getting political again. Sorry. PJ
 
WillR said:
Welcome to the excitement! :eagerness:
I tried to rebuild my ZS. It did not work out well. I got it all back together and could never get it tuned again.
Click to expand...

Same here - I rebuilt it, added a manual choke, spent about what I spent on getting the SU rebuilt. I keep it in case a subsequent owner wants to return the car to original. I figure it would be a good thing to beat him/her with until they change their mind.
 
I must wonder why you guys go to all that expence of changing the stromburg carburator. It only displays the lack of understanding of the unit. I admit the stromburg is a strange bird and there is very littie suport for spare parts and or info. But if the stromburg is propperly adjusted it will perform with the best.

I have one on a 1977 MGB and for a long time I cussed it but now that I understand more how it works I have no quarrel with it, it even passes Utah emissions with flying colors.
 
fixitright said:
I admit the stromburg is a strange bird and there is very littie suport for spare parts and or info.
Click to expand...

You're half-right, fixit, the Stromberg is a strange bird, indeed. A "short-pot" version of the original SU, demand type vacuum controlled beastie. But info and support are readily available, an example of such is this forum.

The whole "tapered needle mixture control" business can be seen as counter-intuitive until some study is done.

...of course this comes from one who thinks "wasted spark" ignition is just silly! :jester:

And welcome to the forum! This place is positively stocked with other strange birds. Hope you stick around and join th' flock. :wink:
 
JPSmit said:
I figure it would be a good thing to beat him/her with until they change their mind.
Click to expand...
:lol:
I have mine in a box with all the other original stuff I took off. though I cant see myself selling now Im in this far. More like a life long learning experience. I would like to understand it more. At the time I had spent enough time and money on it and really needed my only car back on the road. So a side draft went in. Though I cant see myself ever being one of those "this is the only and best carb for me" kinda guys. The thing has leaked from day one as much as my ZS ever did.
 
Will, what "side-draft" did you settle on?
 
The 1-3/4 HIF is a fantastic conversion for a later MGB. (with a good engine) What it will not do is fix a bad cam or worn bore. I have a good friend with one and he is very happy. Car runs great. I do not recall what air filter he is running. If you can afford the entry fee its a simple fix for the original carb.
Bob
 
If you are intent upon swapping the ZS175 for a single HIF....look for the HIF6....works the same as an HIF44...and will most likely be less expensive.

The ZS175 is a good carb....the limiting factor of the single-carbed MGB is the combo intake/exhaust manifold.

I highly recommend the switch over to dual HS4's.

K and N Air Filter Taper_1.jpg
 
I dont remember the model Doc. But the make is Weber. I went out to look at the carb but other then the made in spain stamp and a few weber stamps, it has no markings. Fuel leaks out the bottom of the air filter. On a closer look the fuel comes from behind the filter housing where it meats the "throat." Out side of that, the swap worked well for me.
 
Will, if it is a side-draught Weber, it should have the size stamped in the top cover: "40 DCOE ??" That's not a common setup, but the best one IMHO.

Float level may be wrong, needle may not be seating ~or~ there's too much fuel supply pressure.

This is the DCOE on Mitsy's B:


e-bay1.jpg
 
Last edited:
Doc,
what did you use for the shroud to radiator gap filler? It looks much better than the foam!
Rut
 
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